1. 环境友好阻燃材料课题组所培养的研究生名单及其成果列表

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1 1. 环境友好阻燃材料课题组所培养的研究生名单及其成果列表

2 1. 环境友好阻燃材料课题组所培养的研究生名单及其成果列表 序号 姓名 在读时间 1 叶龙健 冯发飞 汤朔 孙楠 当前状态 所取得的成果 毕业 2010 年获北京工商大学学术论文优秀个人 ;2011 年获北京工商大学 优秀硕士学位论文奖 ; 共以第二作者发表 SCI 学术论文 3 篇 ( 导师一作 ); 获授权国家发明专利 2 项 毕业 2013 年获研究生国家奖学金 北京工商大学 优秀研究生奖学金 ; 被评为北京工商大学 三好研究生 ;2014 年被评为北京工商大学 研究生学术之星 ; 与汤朔等 5 人共同获得第八届 优秀研究生学术团队 称号 ; 北京工商大学 科研成果单项奖 ; 共发表 SCI 学术论文 2 篇, 其中 1 篇为第一作者, 1 篇为第二作者 ( 导师一作 ); 获授权国家发明专利 3 项 毕业 2014 年与冯发飞等 5 人共同获得北京工商大学第八届 优秀研究生学术团队 称号 ;2014 年考入北京理工大学, 攻读博士学位 ; 以第一作者发表 SCI 学术论文 4 篇 ; 授权国家发明专利 3 项 毕业 2013 年获得北京工商大学 优秀研究生奖学金 ;2014 年获得北京工商大学 研究生综合奖学金二等奖 ; 被评为北京工商大学 优秀研究生干部 ; 与汤朔等 5 人共同获得北京工商大学第八届 优秀研究生学术团队 称号 ; 2015 年与邱勇等 5 人共同获得北京工商大学第九届 优秀研究生学术团队 称号 ; 获授权国家发明专利 2 项

3 5 邱勇 许梦兰 毕业 2013 年获北京工商大学 优秀研究生奖学金 ; 被评为北京工商大学 三好研究生 ; 获北京工商大学 科研成果单项奖 ;2014 年获得研究生国家奖学金 北京工商大学 研究生综合奖学金一等奖 ; 与汤朔等 5 人共同获得北京工商大学第八届 优秀研究生学术团队 称号 ;2015 年获得北京工商大学 优秀硕士学位论文奖 ; 与孙楠等 5 人共同获得北京工商大学第九届 优秀研究生学术团队 称号 ; 被评为北京工商大学 研究生学术之星 ; 被评为北京市优秀硕士毕业生 ; 被评为北京工商大学优秀硕士毕业生 ;2015 年考入北京理工大学, 攻读博士学位 ; 共发表 SCI 学术论文 8 篇, 其中 5 篇为第一作者,3 篇为第二作者 ( 导师一作 ); 获授权国家发明专利 5 项 毕业 2014 年获得研究生国家奖学金 ; 被评为北京工商大学 三好研究生 ; 获得北京工商大学 研究生综合奖学金一等奖 ; 与汤朔等 5 人共同获得北京工商大学第八届 优秀研究生学术团队 称号 ;2015 年与邱勇等 5 人共同获得北京工商大学第九届 优秀研究生学术团队 称号 ; 以第一作者发表 SCI 学术论文 1 篇 ; 获授权国家发明专利 2 项

4 7 王靖宇 奚望 刘鑫鑫 毕业 2015 年获得北京工商大学 研究生综合奖学金一等奖 ; 被评为北京工商大学 优秀研究生干部 ; 与邱勇等 5 人共同获得北京工商大学第九届 优秀研究生学术团队 ;2016 年被评为北京工商大学 研究生学术之星 ; 被评为北京工商大学 先锋杯 优秀团员 ; 与奚望等 5 人共同获得北京工商大学第十届 优秀研究生学术团队 ; 以第一作者发表 SCI 学术论文 2 篇 ; 获授权国家发明专利 1 项 ;2016 年考入北京理工大学, 攻读博士学位 毕业 2015 年获得北京工商大学 研究生综合奖学金一等奖 ;2016 年获得研究生国家奖学金 ; 被评为北京工商大学材机学院 科技之星 ; 被评为北京工商大学 三好研究生 ; 获得北京工商大学 研究生综合奖学金一等奖 ; 与王靖宇等 5 人共同获得北京工商大学第十届 优秀研究生学术团队 ;2017 年被评为北京工商大学优秀毕业生 ; 以第一作者发表 SCI 学术论文 3 篇 ; 获授权国家发明专利 1 项 ;2017 年考入北京工业大学, 攻读博士学位 毕业 2015 年获得北京工商大学 研究生综合奖学金一等奖 ;2016 年获得北京工商大学 研究生综合奖学金二等奖 ; 被评为北京工商大学 优秀研究生干部 ; 被评为北京工商大学 先锋杯 优秀团员 ; 与王靖宇等 5 人共同获得北京工商大学第十届 优秀研究生学术团队 ;2017 年被评为北京工商大学 优秀团干部

5 10 王士军 王伟 房友友 曹艳芳 李琳珊 李林洁 倪沛 王泽 毕业 2016 年与王靖宇等 5 人共同获得北京工商大学第十届 优秀研究生学术团队 ; 以第一作者发表 SCI 学术论文 2 篇 ; 获授权国家发明专利 1 项 ;2018 年考入北京航空航天大学, 攻读博士学位 毕业 2016 年获得北京工商大学 研究生综合奖学金一等奖 ; 以第二作者发表 SCI 学术论文 2 篇 ( 导师一作 ); 获授权国家发明专利 3 项 在读 2016 年获得北京工商大学 研究生综合奖学金二等奖 ; 与王靖宇等 5 人共同获得北京工商大学第十届 优秀研究生学术团队 ;2017 年获得北京工商大学 研究生综合奖学金一等奖 ; 2017 年获得研究生国家奖学金 ; 以第一作者发表 SCI 学术论文 2 篇 ;2018 年考入北京理工大学, 攻读博士学位 在读 2016 年获得北京工商大学 研究生综合奖学金二等奖 ;2017 年获得北京工商大学 研究生综合奖学金二等奖 ; 以第一作者发表 SCI 论文 1 篇 在读 2017 年获得北京工商大学 研究生综合奖学金一等奖 ; 被评为北京工商大学 三好研究生 ; 获得中国化学会全国高分子学术论文报告会 优秀墙报奖 ; 共以第二作者发表 SCI 论文 2 篇 ( 导师一作 ) 在读 2017 年获得北京工商大学 研究生综合奖学金二等奖 ; 获得年第八届火安全材料学术会议优秀论文奖 ; 以第一作者发表 SCI 论文 1 篇 在读 2017 年获得北京工商大学 研究生综合奖学金二等奖 ; 以第一作者发表 SCI 论文 1 篇 在读获北京工商大学 2017 年度研究生综合奖学金二等奖

6 18 郭超 吴笑 在读 2017 年获得北京工商大学 研究生综合奖学金二等奖 ; 发表 SCI 论文 1 篇 ( 导师一作, 学生二作 ) 在读 2017 年获得北京工商大学 研究生综合奖学金二等奖 发表 SCI 论文 1 篇 ( 导师一作, 学生二作 );2018 年考入中科院宁波材料所, 攻读博士学位

7 2 团队研究生所取得的各类荣誉

8 2 团队研究生所取得的各类荣誉 团队培养的研究生在校期间取得的各类荣誉 序号 奖励名称 获奖学生姓名 获奖时间 1 硕士研究生国家奖学金 冯发飞 硕士研究生国家奖学金 邱勇 硕士研究生国家奖学金 许梦兰 硕士研究生国家奖学金 奚望 硕士研究生国家奖学金 房友友 2017

9 序号奖励名称获奖学生姓名获奖时间 6 北京市 优秀硕士毕业生 邱勇 2015 序号奖励名称获奖学生姓名获奖时间 7 8 北京工商大学 优秀硕士毕业生 北京工商大学 优秀硕士毕业生 邱勇 2015 奚望 2017

10 序号奖励名称获奖学生姓名获奖时间 北京工商大学第八届 优秀研究生学术团队 北京工商大学第九届 优秀研究生学术团队 北京工商大学第十届 优秀研究生学术团队 汤朔 冯发飞 邱勇 孙楠 许梦兰邱勇 孙楠 许梦兰 王靖宇王靖宇 奚望 刘鑫鑫 王士军 房友友

11 序号 奖励名称 获奖学生姓名 获奖时间 12 北京工商大学 研究生学术之星 冯发飞 北京工商大学 研究生学术之星 邱勇 北京工商大学 研究生学术之星 王靖宇 北京工商大学 学术论文优秀个人 叶龙健 北京工商大学材机学院 科技之星 奚望 2016

12 序号奖励名称获奖学生姓名获奖时间 17 北京工商大学 三好研究生 冯发飞 北京工商大学 三好研究生 邱勇 北京工商大学 三好研究生 许梦兰 北京工商大学 三好研究生 奚望 北京工商大学 三好研究生 李琳珊 2017

13 序号 奖励名称 获奖学生姓名 获奖时间 22 北京工商大学 优秀研究生奖学金 邱勇 北京工商大学 优秀研究生奖学金 冯发飞 北京工商大学 优秀研究生奖学金 孙楠 北京工商大学 研究生综合奖学金一等奖 房友友 北京工商大学 研究生综合奖学金一等奖 邱勇 北京工商大学 研究生综合奖学金一等奖 许梦兰 北京工商大学 研究生综合奖学金一等奖 刘鑫鑫 北京工商大学 研究生综合奖学金一等奖 王靖宇 北京工商大学 研究生综合奖学金一等奖 奚望 北京工商大学 研究生综合奖学金一等奖 奚望 北京工商大学 研究生综合奖学金一等奖 李琳珊 北京工商大学 研究生综合奖学金二等奖 孙楠 北京工商大学 研究生综合奖学金二等奖 刘鑫鑫 北京工商大学 研究生综合奖学金一等奖 王伟 北京工商大学 研究生综合奖学金二等奖 曹艳芳 北京工商大学 研究生综合奖学金二等奖 房友友 北京工商大学 研究生综合奖学金二等奖 李林洁 北京工商大学 研究生综合奖学金二等奖 王泽 2017

14 北京工商大学 研究生综合奖学金二等奖 北京工商大学 研究生综合奖学金二等奖 北京工商大学 研究生综合奖学金二等奖 北京工商大学 研究生综合奖学金二等奖 倪沛 2017 吴笑 2017 郭超 2017 曹艳芳 2017

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17 序号奖励名称获奖学生姓名获奖时间 北京工商大学 科研成果单项奖 北京工商大学 科研成果单项奖 邱勇 2013 冯发飞 2013 序号奖励名称获奖学生姓名获奖时间 北京工商大学 优秀硕士学位论文奖 北京工商大学 优秀硕士学位论文奖 第八届全国火安全材料学术会议 优秀论文奖 全国高分子学术论文报告会 优秀墙报奖 叶龙健 2011 邱勇 2015 李林洁 2017 李琳珊 2017

18 序号奖励名称获奖学生姓名获奖时间 北京工商大学 优秀研究生干部 北京工商大学 优秀研究生干部 北京工商大学 优秀研究生干部 北京工商大学 先锋杯 优秀团员北京工商大学 先锋杯 优秀团员北京工商大学 优秀团干部 孙楠 2014 王靖宇 2015 刘鑫鑫 2016 刘鑫鑫 2016 王靖宇 2016 刘鑫鑫 2017

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20 已毕业硕士研究生所获的各项荣誉 序号奖励名称获奖学生姓名获奖时间 1 北京华腾 最佳新人奖 冯发飞 北京华腾 科技成果优秀奖 冯发飞 北京华腾 科技成果特等奖 冯发飞 广东新会经济开发区 优秀党员 冯发飞 北京华腾 总经理特别嘉奖 冯发飞 第三期北京化工集团技术革新能手 北京化学工业集团 优秀共产党员 冯发飞 2017 冯发飞 广东银禧 优秀员工 许梦兰 2017

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22 3 团队研究生所发表的 SCI 论文列表

23 3 团队研究生所发表的 SCI 论文列表 序号 作者期刊名称年份期数 / 卷数 / 页码 ShuoTang, LijunQian*, YongQiu. Menglan Xu, Yajun Chen, Lijun Qian*, Jingyu Wang, Shuo Tang. Fafei Feng, Lijun Qian*. Wang Xi, Lijun Qian*, Yong Qiu, Yajun Chen. Jingyu Wang, Lijun Qian*, Bo Xu, Wang Xi, Xinxin Liu. Wang Xi, Lijun Qian*, Yajun Chen, Jingyu Wang, Xinxin Liu. Yong Qiu, Lijun Qian*, Wang Xi, Xinxin Liu. Shuo Tang, Lijun Qian*, Xinxin Liu, Yuping Dong*. Jingyu Wang, Lijun Qian*, Zhigang Huang, Youyou Fang, Yong Qiu. Shijun Wang, Fei Xin*, Yu Chen, Lijun Qian, Yajun Chen. Journal of Applied Polymer Science Journal of Applied Polymer Science Polymer Composites Polymers for Advanced Technologies Polymer Degradation and Stability Polymer Degradation and Stability Journal of Applied Polymer Science Polymer Degradation and Stability Polymer Degradation and Stability Polymer Degradation and Stability (15): (21): (2): (6): : : (14): : : :

24 Wang Xi, Lijun Qian*, Zhigang Huang, Yanfang Cao, Linjie Li. Yong Qiu, Lijun Qian*, Wang Xi. Yong Qiu, Zhen Liu, Lijun Qian*, Jianwei Hao*. Yanfang Cao, Lijun Qian*, Yajun Chen, Ze Wang. YouyouFang, LijunQian*, ZhigangHuang. Yong Qiu, Volker Wachtendorf, Patrick Klack, Lijun Qian*, Zhen Liu. Youyou Fang, Lijun Qian*, Zhigang Huang, Shuo Tang, Yong Qiu. Yong Qiu, Zhen Liu, Lijun Qian*, Jianwei Hao*. Shuo Tang, Volker Wachtendorf, Patrick Klack, Lijun Qian*, Yuping Dong, Bernhard Schartel*. Linjie Li, Yajun Chen*, Lijun Qian*, Bo Xu, Wang Xi. Pei Ni, Youyou Fang, Lijun Qian*, Yong Qiu. Polymer Degradation and Stability Rsc Advances 2016 Journal of Analytical and Applied Pyrolysis Journal of Applied Polymer Science Polymer International Polymer International : (61): : (30): (5): Rsc Advances 2017 Rsc Advances (12): (73): (81): Rsc Advances (2): Journal of Applied Polymer Science Journal of Applied Polymer Science : (6):45815

25 Shuo Tang, Lijun Qian*, Yong Qiu, Yuping Dong*. Shijun Wang, Lijun Qian*, Fei Xin. Lijun Qian*, Longjian Ye, Xinlei Han, Guozhi Xu, Ye Meng. Lijun Qian*, Longjian Ye, Guozhi Xu, Jing Liu, Jiaqing Guo. Lijun Qian*, Longjian Ye, Yong Qiu, Shuren Qu. Lijun Qian*, Yong Qiu, Jing Liu, Fei Xin, Yajun Chen. Lijun Qian*, Yong Qiu, Nan Sun, Menglan Xu, Guozhi Xu, Fei Xin, Yajun Chen. Lijun Qian*, Fafei Feng, Shuo Tang. Lijun Qian*, Yong Qiu, Jingyu Wang, Wang Xi. Yajun Chen*, Xiaojun Mao, Lijun Qian*, Chunzhuang Yang. Yajun Chen*, Linshan Li, Wei Wang, Qian Lijun*. Yajun Chen*, WeiWang, ZhiqiLiu, Yuanyuan Yao, Lijun Qian*. Polymers for Advanced Technologies Polymer Composites Progress in Chemistry Polymer Degradation and Stability Polymer 2011 Journal of Applied Polymer Science Polymer Degradation and Stability (1): (2): (9): (6): (24): (3): : Polymer (1): Polymer : Integrated Ferroelectrics Journal of Applied Polymer Science Journal of Applied Polymer Science (1): : (13):44660

26 Bo Xu*, Xiao Wu, Lijun Qian*, Yong Qiu, Shuo Tang, Wang Xi, Youyou Fang. Yajun Chen*, WeiWang, YongQiu, Linshan Li, Lijun Qian*, Fei Xin. Fei Xin*, Chao Guo, Yajun Chen, Hailong Zhang, Lijun Qian. Yajun Chen*, Linshan Li, Lifeng Xu, Lijun Qian*. Journal of Fire Sciences Polymer Degradation and Stability Rsc Advances 2017 Journal of Applied Polymer Science (4): : (75): DOI: /app.46334

27 The Effect of Morphology on the Flame-Retardant Behaviors of Melamine Cyanurate in PA6 Composites Shuo Tang, Li-jun Qian, Yong Qiu, Nan Sun Department of Materials Science & Engineering, Beijing Technology and Business University, Beijing , People s Republic of China Correspondence to: L. Qian (E- mail: augusqian@163.com) ABSTRACT: Three types of melamine cyanurate (MCA) with micrometer-size sphere-like, micrometer-scale rod-like, and nanometerscale flake-like morphologies were synthesized by changing the chemical circumstances of the reactions. The microcosmic morphologies of MCA were characterized via scanning electron microscopy and X-ray diffraction. After the MCAs with different morphologies were incorporated into polyamide 6 (PA6), the flame-retardant properties of the MCA/PA6 composites were investigated using the limited oxygen index (LOI), UL94, and cone calorimeter tests. The MCA/PA6 composites with nanometer-scale flake-like MCA obtained an LOI value of 29.5% and a UL94 V-0 rating, which were higher than those with micrometer-size sphere-like and rod-like MCAs. However, the different morphologies did not affect the heat release rate, total smoke release, average carbon monoxide yield, and average carbon dioxide yield based on the cone calorimeter. The flame-retardant mechanism of MCAs with different morphologies was investigated via thermal gravimetric analysis (TGA) and TGA-Fourier transform infrared spectra. The results show that the different morphologies of MCA resulted in different dispersed evenness of MCA. Further, the nanometer-scale flake-like morphology of MCA brought more interactions of hydrogen bond between MCA and PA6, which resulted in the delay of MCA decomposition and the enhancement of MCA flame-retardant effect. The nanometer-scale flake-like MCA had a better performance compared with the other samples because of the delaying and even release of flame-retardant effect by the decomposition of evenly dispersed MCA. VC 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, KEYWORDS: morphology; flame-retardant; melamine cyanurate; PA6 Received 25 November 2013; accepted 4 February 2014 DOI: /app INTRODUCTION Polyamide 6 (PA6) is an important engineering plastic because of its good physical mechanical properties, attrition resistance, and oil resistance. PA6 is widely employed in modern industrial applications. 1 3 Although PA6 possesses a limiting oxygen index (LOI) value of 24% and a UL94 V-2 rating, its flame retardancy should still be improved to meet the flame-retardant requirements of its application in several areas. 4 6 Therefore, inorganic flame-retardants melamine cyanurate (MCA), 5 organic alkyl phosphate, 7 and brominated polystyrene have all been incorporated to flame-retardant PA6. 8 Similar to fillers, 9 inorganic flame retardants have to be added in greater amounts to achieve a satisfactory flame-retardant performance. These flame retardants provide different effects on the comprehensive properties of the material because of their different morphologies and surface properties In recent years, flame retardants with particular morphologies have been reported, such as 4ZnOB 2 O 3 H 2 O with nanostructures, 14,15 nano-magnesium hydroxide, 9 and NaAl(OH) 2 CO 3 whiskers. 16 Particular flame retardants enhance the char yield, 14,15 delay the time to ignition, 9 decrease the mean heat release rate (HRR), 9 or increase the mechanical reinforcement of the material. 16 Namely, several flame retardants with different morphologies show distinct advantages in enhancing the flame-retardant properties compared with the others. 9,14 16 Thus, morphology optimization has increasingly become an alternative way to improve the flame retardancy of additives. MCA has been widely utilized as an important halogen-free flame retardant in unfilled polyamides. 17 As an inorganic flame retardant, MCA also needs to be incorporated in PA6 by approximately 15 wt % to obtain a flame retardant PA6 with UL94 V-0 rating Ahigh addition level usually causes a negative effect on the properties of PA6, but MCA can be controlled and prepared to obtain several products with different morphologies. This condition may result in different effects on the flame retardancy and mechanical properties of MCA. Therefore, our recent research focuses more on the relationship between their morphologies and properties. VC 2014 Wiley Periodicals, Inc (1 of 8) J. APPL. POLYM. SCI. 2014, DOI: /APP.40558

28 Component Ratio Effects of Hyperbranched Triazine Compound and Ammonium Polyphosphate in Flame-Retardant Polypropylene Composites Menglan Xu, Yajun Chen, Lijun Qian, Jingyu Wang, Shuo Tang Department of Materials Science & Engineering, Beijing Technology and Business University, Beijing , People s Republic of China Correspondence to: L. Qian (E- mail: augusqian@163.com) ABSTRACT: A hyperbranched derivative of triazine group (EA) was synthesized by elimination reaction between ethylenediamine and cyanuric chloride. The different-mass-ratio EA and ammonium polyphosphate (APP) were mixed and blended with polypropylene (PP) in a constant amount (25%) to prepare a series of EA/APP/PP composites. The component ratio effect of EA/APP on the flame-retardant property of the EA/APP/PP composites was investigated using the limiting oxygen index (LOI), vertical burning (UL- 94), and cone calorimetry tests. Results indicated that the EA/APP/PP (7.50/17.50/75.00) composite with the appropriate EA/APP mass ratio had the highest LOI, UL94 V-0 rating, lowest heat release rate, and highest residue yield. These results implied that the appropriate EA/APP mass ratio formed a better intumescent flame-retardant system and adequately exerted their synergistic effects. Furthermore, average effective combustion heat values revealed that EA/APP flame retardant possessed the gaseous-phase flameretardant effect on PP. Residues of the EA/APP/PP composites were also investigated by scanning electron microscopy, Fouriertransform infrared, and X-ray photoelectron spectroscopy. Results demonstrated that the appropriate EA/APP mass ratio can fully interact and lock more chemical constituents containing carbon and nitrogen in the residue, thereby resulting in the formation of a dense, compact, and intumescent char layer. This char layer exerted a condensed-phase flame-retardant effect on EA/APP/PP composites. VC 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, KEYWORDS: blends; flame retardance; polyolefins Received 15 February 2014; accepted 12 May 2014 DOI: /app INTRODUCTION In recent years, intumescent flame retardants (IFRs) have been widely used in polyolefins (e.g., polypropylene (PP) and polyethylene) because of their outstanding advantages, such as low smoke, nontoxicity, no corrosive gas, no dripping and halogenfree, etc. 1 4 In general, IFR is mainly composed of three basic constituents, namely, acid source, charring agent, and blowing agent. 5 A classical component of IFR is the ammonium polyphosphate (APP)/pentaerythritol/melamine system, which has been given more attention and deeply investigated by several flame-retardant study groups. 6 8 However, the flame-retardant efficiency and thermal stability of traditional IFR additives still need further enhancement compared with bromine-containing flame retardants. 9 Commonly, the charring agents in IFR are polyols (e.g., pentaerythritol, dipentaerythritol, mannitol, and sorbitol), but their thermal stabilities, charring, and flameretardant efficiencies are inadequate when they are applied in flame-retardant polyolefins. 10 In order to increase the flame-retardant efficiency of IFR, many methods have already been utilized, such as addition of synergist zeolite in IFR additives, adjustment of the relative ratio among three components of IFR, 10 and synthesis of some novel charring agents with high thermal stability. In order to obtain more effective IFRs, two novel kinds of charring agents have been synthesized, namely, polyol phosphate compounds and triazine derivatives. 14,15 However, small molecules containing triazine ring used as charring agents in IFR have to be improved in thermal stability, flame retardant efficiency, and migration onto the surface of the matrix. 5 In recent years, the hyperbranched and linear macromolecules containing triazine ring structures have received more attention because of their high thermal stability, charring, and flame-retardant efficiencies derived from the structural character of triazine ring In this current work, a charring additive-hyperbranched derivative of triazine (EA) was synthesized and characterized. Then the EA/APP IFR was applied in PP to investigate its flame- VC 2014 Wiley Periodicals, Inc (1 of 8) J. APPL. POLYM. SCI. 2014, DOI: /APP.41006

29 The Flame Retardant Behaviors and Synergistic Effect of Expandable Graphite and Dimethyl Methylphosphonate in Rigid Polyurethane Foams Fafei Feng, Lijun Qian Department of Materials Science and Engineering, Beijing Technology and Business University, Beijing , China A series of flame-retardant rigid polyurethane foams (RPUFs) containing dimethyl methylphosphonate (DMMP) and expandable graphite (EG) were prepared by box-foaming. The RPUFs were characterized by thermogravimetric analysis (TGA), the limiting oxygen index (LOI), cone calorimeter, and scanning electron microscope (SEM). The decomposition process of DMMP was investigated by Pyrolysis-Gas Chromatography/ Mass Spectroscopy (Py-GC/MS). Accordingly, their flame retardant behaviors and mechanism were also discussed. The results show that the DMMP/EG system can linearly enhance the LOI value from 19.2% of the pure RPUF to 33.0% of RPUFs containing 16 wt% flame retardant. In addition, the DMMP/EG system also remarkably increases yields of the residual char and drastically decreases the peak value of heat release rate (PHRR), heat release rate (HRR), total heat release (THR), total smoke release (TSR), and the yields of CO (COY). In the flame retardant RPUFs, when the matrix is ignited, the flame retardant DMMP should be decomposed to gaseous PO 2 fragments, which can inhibit free radical chain reaction of flammable alkyl free radical from the decomposed matrix; whereas the flame retardant EG can rapidly expand and form loose and wormlike expanding graphite char layer accordingly, which can hinder the heat transmission to the inner matrix and reduce decomposing velocity of matrix. After the combination of the two flame retardant effects, the DMMP/EG flame retardant system provides the matrix with better flame retardant effects than one of them does. Namely, it shows excellent gas-condensed biphase synergistic effect. POLYM. COMPOS., 00: , VC 2013 Society of Plastics Engineers Correspondence to: Lijun Qian; qianlj@th.btbu.edu.cn Contract grant sponsor: Importation and Development of High-Caliber Talents Project of Beijing Municipal Institutions; contract grant number: CIT&TCD Additional Supporting Information may be found in the online version of this article. DOI /pc Published online in Wiley Online Library (wileyonlinelibrary.com). VC 2013 Society of Plastics Engineers INTRODUCTION Polyurethane, made by the reaction between diisocyanates or polyisocyanates and diols or polyols, has already been one of the most important polymers, which has a wide range of applications such as coatings, flexible or rigid foams, adhesives, sealants, synthetic leathers, membranes, and elastomers in both industry and daily life [1, 2]. Typically, rigid polyurethane foams (RPUFs) are extensively used as thermal insulation materials due to lower thermal conductivity and better physical and mechanical properties than those of polystyrene foams. However, the application of RPUFs is restricted in the construction industry because of the high flammability, where the stringent standards on the flammability of materials are imposed [3]. The flammability of flexible or rigid polyurethane foams is caused by their porous cellular structure full of gases. In the past years, considerable efforts have been made to enhance the flame retardancy of RPUFs from both academy and industry. So far, inorganic fire-retardants, e.g., alumina trihydrate (ATH) [4], expandable graphite (EG) [5, 6], and ammonium polyphosphate (APP) [7 9], and organic ones [10, 11], e.g., triethylphosphate (TEP) [12], dimethyl methylphosphonate (DMMP), tris-(2-chloropropyl)-phosphate (TCPP) [13], and tris-(2-chloroethyl)- phosphate (TCEP) all have been incorporated into RPUFs to investigate the flame retardant effects, respectively. Expandable graphite (EG) is a kind of effective inorganic intumescent halogen-free flame retardant for most of polymeric materials, and has been widely used in the RPUFs in recent years. Several groups have researched the flame retardant effects of different-sized expandable graphite particles and different addition amount in rigid polyurethane foams [14 16]. It discloses that sulfuric acid intercalated between layers of graphite boils and releases vapors when EG is rapidly heated, which results in exfoliation and expansion of the graphite slice. Furthermore, EG and other constituents (e.g., hollow glass microsphere [17], whisker silicon oxide [18], organic phosphate [19]) as flame retardant systems for polyurethane foams have been POLYMER COMPOSITES 2013

30 Research article Received: 29 July 2015, Revised: 05 September 2015, Accepted: 29 September 2015, Published online in Wiley Online Library (wileyonlinelibrary.com) DOI: /pat.3714 Flame-retardant behavior of bi-group molecule derived from phosphaphenanthrene and triazine groups on polylactic acid Wang Xi, Lijun Qian*, Yong Qiu and Yajun Chen The flame-retardant polylactic acid (PLA) has been prepared via mixing the flame retardant TGIC-DOPO derived from phosphaphenanthrene and triazine groups into matrix. The flame retardancy of TGIC-DOPO/PLA composites was characterized using the limiting oxygen index (LOI), vertical burning test (UL94), and cone calorimeter test. Results reveal that the 10%TGIC-DOPO/PLA composite obtained 26.1% of LOI and passed UL94 V-0 rating. The flameretardant mechanism of PLA composites was characterized via thermogravimetric analysis (TGA), pyrolysis gas chromatography/mass spectroscopy, and TGA-Fourier transform infrared. It discloses that TGIC-DOPO promoted PLA decomposing and dripping early, and it also released the fragments with quenching and dilution effects. These actions of TGIC-DOPO contribute to reducing the burning intensity and extinguishing the fire on droplets, thus imposing better flame retardancy to PLA. When TGIC-DOPO was partly replaced by melamine cyanuric with dilution effect and hexa-phenoxy-cyclotriphosphazene with quenching effect in composites respectively, the results confirm that TGIC-DOPO utilize well-combination in dilution effect and quenching effect to flame retard PLA. Copyright 2015 John Wiley & Sons, Ltd. Keywords: flame-retardant; PLA; DOPO; quenching effect INTRODUCTION Recently, because of environmental pollution and nondegradable shortage of many petrochemicals, the environment-friendly biodegradable materials have been rapidly developed. Polylactic acid (PLA) is a kind of biodegradable polymer, which has received more extensive attentions. PLA has many advantages: biodegradability, abundant renewable resources, excellent mechanical properties including high strength and high stiffness, appropriate thermal properties, and electrical properties. [1,2] It can be widely used instead of some general plastic in electronic products, textile industry, and disposable products. However, PLA is an extremely flammable material with dripping during combustion, which restrains its application in electrical fields. Therefore, the research on flame-retardant PLA is necessary. [3 7] In recent years, non-halogen flame-retardant PLA composites have already been extensively researched. [8 11] Several systems have been applied to impart flame retardancy to PLA, such as phosphorus-containing silsesquioxane, [12 14] intumescent flame retardants, [15 19] and nitrogen phosphorus flame retardants. [20 24] In addition to organic flame retardants, inorganic flame retardants including zinc aluminum layered double hydroxide, [25] carbon nanotubes, [26] sepiolite nanoclays, [26,27] nanosized carbon black combined with Ni 2 O 3, [28] and inorganic nanoparticles [29 31] can effectively enhance flame-retardant properties of PLA. Although these flame retardants revealed better flameretardant performance, the PLA often need blend with more than 20 wt% flame retardants to obtain excellent flame retardancy. [32 34] Therefore, the flame retardants that can melt well with PLA and work in high efficiency still need to be explored for meeting the commercial demands. Recently, a kind of hyperbranched phosphorus nitrogen flame retardant (HBPE) was reported, in which only 2 wt% HBPE in PLA composite can exert excellent flame-retardant effect by means of gas-phase flame-retardant mechanism. [24] The result disclosed a high-efficiency way of flame retarding PLA by gas-phase flame-retardant mode. The flame retardant TGIC-DOPO (Scheme 1) with high efficiency, which is derived from phosphaphenanthrene and triazine-trione groups, was mentioned in the previous reported works. [22] Because of the molten property after 107 C and rich hydroxyl groups of TGIC-DOPO, it can blend well with PLA. In our present work, the flame-retardant TGIC-DOPO was blended with PLA to prepare the flame-retardant PLA composites. The flame retardancy of PLA composites was investigated, and the flame-retardant mechanism of TGIC-DOPO in PLA composites was also illuminated. EXPERIMENTAL Materials (1) Polylactic acid (melt index of 2.99 g/10 min) was purchased from Nature Works; (2) the flame retardant TGIC-DOPO was synthesized using the method in the previous reported work [22] ; (3) melamine cyanurate (MCA) was supplied by Jinan Taixing Fine * Correspondence to: Lijun Qian, ZongheBuilding No. 403, Fucheng Road No. 33, Haidian District, Beijing, China. qianlj@th.btbu.edu.cn Financial supports were provided by the National Nature Science Foundation (no ). W. Xi, L. Qian, Y. Qiu, Y. Chen Department of Materials Science and Engineering, Beijing Technology and Business University, Beijing , China Polym. Adv. Technol. (2015) Copyright 2015 John Wiley & Sons, Ltd.

31 Polymer Degradation and Stability 122 (2015) 8e17 Contents lists available at ScienceDirect Polymer Degradation and Stability journal homepage: Synthesis and characterization of aluminum poly-hexamethylenephosphinate and its flame-retardant application in epoxy resin Jingyu Wang, Lijun Qian *, Bo Xu, Wang Xi, Xinxin Liu Department of Materials Science & Engineering, Beijing Technology and Business University, Beijing , PR China article info abstract Article history: Received 21 August 2015 Received in revised form 9 October 2015 Accepted 11 October 2015 Available online 19 October 2015 Keywords: Flame retardant Phosphinate Epoxy resin Alkyl-phosphinate A flame retardant additive, aluminum poly-hexamethylenephosphinate (APHP) with a polymeric structure was synthesized from 1,5-hexadiene, hypophosphorous acid and aluminum ions. The molecular structure of APHP and thermal stability were characterized by solid nuclear magnetic resonance, Fourier transform infrared and thermogravimetric analysis. Then, APHP was applied into diglycidyl ether of bisphenol-a cured by 4,4 0 -diamino-diphenylmethane. APHP showed flame-retardant effect on the epoxy thermosets in limited oxygen index (LOI), UL94 vertical test and cone calorimeter. The thermosets with only 4 wt.% APHP obtained an LOI value of 32.7% and reached the UL94 V-1 rating. The APHP/EP thermosets decreased the pk-hrr, THR and av-ehc values, decreased CO 2 Y and enhanced the COY ratios, and also reserved more residual char comparing with neat thermoset. The less incorporation of APHP in thermosets will impose the better flame retardancy to epoxy thermosets. The flame-retardant effect of APHP was resulted by its two main pyrolyzed contents phosphorus and alkyl-phosphinic fragments. In condensed phase, the phosphorus-containing contents facilitated to the higher char yields and the formation of intumescent char layer, which led to a reduction of the released fuel and a strong barrier effect to weaken the combustion intensity. In gas phase, the PO, PO 2 and alkyl-phosphinic fragments with quenching effect were released from the phosphorus-containing contents, and can decrease the heat release and weaken the combustion intensity Elsevier Ltd. All rights reserved. 1. Introduction In the recent years, high-performance halogen-free flameretardant systems have become one of the most noteworthy topics in flame retardant fields to avoid the environment problems of several halogen-containing flame retardants [1]. Phosphorusbased flame retardants like phosphaphenanthrene, phosphazene, phosphate and phosphinate were all considered as effective contents to most of polymers [2,3]. Due to outstanding flame-retardant effect and water resistance, alkyl-substituted phosphinates were especially taken more attention in both commercial application and scientific research [4]. Alkyl-substituted phosphinates were first prepared and commercialized by Clariant Co. Series of metal alkyl-substituted * Corresponding author. Zonghe Building No.403, Fucheng Road NO.33, Haidian District, Beijing, PR China. address: qianlj@th.btbu.edu.cn (L. Qian). phosphinates, especially aluminum salt of diethylphosphinic acid (AlPi), have been designed, synthesized and applied [5e9]. Itis reported that AlPi and its composites are commercially available as Exolit OP1230, 1240, 1312, 1200, 1311 [10e14]. AlPi was found to be well working in polyamides and glass fiber reinforced polyamides, poly(ethylene terephthalate) and poly(butylene terephthalate) [4,15e18], also in poly(methyl methacrylate), polyurethane, and polyolefin [19e22]. In addition, some other kinds of alkylsubstituted phosphinates, e.g. aluminum diisobutylphosphinate and aluminum phenylphosphinate, were also proven to be effectively flame retardant in some certain polymer composites [23e25]. Polyamides and polyesters system were most researched in the flame-retardant application of AlPi. Ramani et al. investigated the flame-retardant mechanism of AlPi in combination with melamine polyphosphate and organically modified montmorillonite nanoclay in PA6 [26]. Schartel et al. applied AlPi in synergize with melamine polyphosphate and zinc borate in glass-fiber-reinforced PA66 and found that the AlPi acted mainly by flame inhibition [10]. Horrocks et al. investigated the combined effects and / 2015 Elsevier Ltd. All rights reserved.

32 Polymer Degradation and Stability 122 (2015) 36e43 Contents lists available at ScienceDirect Polymer Degradation and Stability journal homepage: Addition flame-retardant behaviors of expandable graphite and [bis(2-hydroxyethyl)amino]-methyl-phosphonic acid dimethyl ester in rigid polyurethane foams Wang Xi, Lijun Qian *, Yajun Chen, Jingyu Wang, Xinxin Liu Department of Materials Science & Engineering, Beijing Technology and Business University, Beijing , PR China article info abstract Article history: Received 2 September 2015 Received in revised form 11 October 2015 Accepted 15 October 2015 Available online 19 October 2015 Keywords: Flame retardant Addition flame-retardant effect PU EG The flame-retardant rigid polyurethane foams (RPUFs) with [bis(2-hydroxyethyl)amino]-methyl-phosphonic acid dimethyl ester (BH)/expandable graphite (EG) were prepared via box-foaming in our laboratory. The flame retardancy of RPUFs with BH and EG was characterized using the limiting oxygen index (LOI), cone calorimeter test. The results show that BH/EG system obviously increased the LOI value, decreased the heat release rate and mass loss rate, and enhanced the char yields of RPUFs. The results reveal that the addition flame-retardant effects from BH and EG. The flame-retardant mechanism of RPUFs was also detected using scan electronic microscopic and pyrolysis-gas chromatography/mass spectroscopy. According to the test results, BH promoted forming the firm phosphorus-containing char layer, which adhered the loose and worm-like expanded graphite in condense phase. Then, the compacter and thicker char layer was obtained. It will exert well obstructing property to fire in condensed phase. Moreover, BH also will generate dimethyl methylphosphonate (DMMP) gas and then be pyrolyzed to PO and PO 2 free radicals in gaseous phase during combustion, which can quench the flammable free radicals from the matrix and terminate the free radical chain reaction of combustion. After the combination of the bi-phase flame-retardant effects, BH/EG flame-retardant system brought addition flame-retardant effects, and thus providing the better flame retardancy to matrix than one of them does. Moreover, the results of compressive strength, thermal conductivity and apparent density reveal that BH/EG/RPUF can meet the demand for the application in reality Elsevier Ltd. All rights reserved. 1. Introduction Rigid polyurethane foams (RPUFs) are a kind of polymer material which is widely used in various industrial fields such as refrigeration, petroleum, petroleum plant and construction. RPUFs have many excellent properties, which includes excellent electrical insulating property, light weight, high specific strength, low heat conductivity [1e5]. Especially, RPUFs have a low coefficient of thermal conductivity (K). Therefore, they could replace currently used polystyrene insulating materials [6e10]. However, the application of neat RPUF has been restricted by the combustible property because RPUF is constituted by porous cellular structure, * Corresponding author. Department of Materials Science & Engineering, Beijing Technology and Business University, No.11, Fucheng Road, Haidian District, Beijing , PR China. address: qianlj@th.btbu.edu.cn (L. Qian). which increases the contact area between the material and air. After ignition, RPUF generated a large amount of heat in a short period of time with releasing harmful smoke containing CO, HCN, and other toxic gases. During RPUF burning, the smoke will damage the human body and environment. Therefore, to research flameretardant RPUFs is necessary [11e13]. In the past years, both academy and industry paid considerable efforts to enhance the flame retardancy of RPUFs [14,15]. In recent years, due to the less health hazard, the flame retardants containing phosphorus/nitrogen applied in RPUF have received more attentions [16]. The commonly used flame retardants in RPUFs can be divided into addition-type and reaction-type. According to the previous literature, some researchers used a lot of addition-type flame retardants, such as ammonium polyphosphate (APP) [17], expandable graphite (EG) [18e20], triphenylphosphate(tpp) [21], tris(1-chloro-2-propyl) phosphate (TCPP) [22], triethyl phosphate (TEP) [23], dimethyl methylphosphonate (DMMP) [24,25], hexaphenoxy-cyclotriphosphazene (HPCP) [26], and montmorillonite / 2015 Elsevier Ltd. All rights reserved.

33 Joint flame-retardant effect of triazine-rich and triazine/ phosphaphenanthrene compounds on epoxy resin thermoset Yong Qiu, Lijun Qian, Wang Xi, Xinxin Liu Department of Materials Science and Engineering, Beijing Technology and Business University, Beijing , People s Republic of China Correspondence to: L. Qian (E- mail: qianlj@th.btbu.edu.cn) ABSTRACT: To obtain a more efficient flame-retardant system, the extra-triazine-rich compound melamine cyanurate (MCA) was coworked with tri(3-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide-2-hydroxypropan-1-yl)21,3,5-triazine-2,4,6-trione (TGIC DOPO) in epoxy thermosets; these were composed of diglycidyl ether of bisphenol A (DGEBA) epoxy resin and 4,4 0 -diaminodiphenyl methane (DDM). The flame-retardant properties were investigated by limited oxygen index measurement, vertical burning testing, and cone calorimeter testing. In contrast to the DGEBA/DDM (EP for short) thermoset with a single TGIC DOPO, a better flame retardancy was obtained with TGIC DOPO/MCA/EP. The 3% TGIC DOPO/2% MCA/EP thermoset showed a lower peak heat-release rate value, a lower effective heat of combustion value, fewer total smoke products, and lower total yields of carbon monoxide and carbon dioxide in comparison with 3% TGIC DOPO/EP. The results reveal that MCA and TGIC DOPO worked jointly in flame-retardant thermosets. The dilution effect of MCA, the quenching effect of TGIC DOPO, and their joint action inhibited the combustion intensity and imposed a better flame-retardant effect in the gas phase. The 3% TGIC DOPO/2% MCA/EP thermoset also exhibited an increased residue yield, and more compositions with triazine rings were locked in the residues; this implied that MCA/TGIC DOPO worked jointly in the condensed phase and promoted thermoset charring. The results reveal the better flame-retardant effect of the MCA/TGIC DOPO system in the condensed phase. Therefore, the joint incorporation of MCA and TGIC DOPO into the EP thermosets increased the flame-retardant effects in both the condensed and gas phases during combustion. This implied that the adjustment to the group ratio in the flame-retardant group system endowed the EP thermoset with better flame retardancy. VC 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, KEYWORDS: composites; flame retardance; thermosets Received 31 July 2015; accepted 19 November 2015 DOI: /app INTRODUCTION Flame-retardant modification is an effective way to impose flame retardancy to flammable materials. 1 3 To construct novel flame retardants with higher flame-retardant efficiencies, many researches have combined some known efficient characteristic structures or functional groups together; these have included triazine, 4 cyclotriphosphazene, 5 phosphaphenanthrene, 6 silsesquioxane, 7 and phosphonate. 8 Thishasbecomeoneofthemostfeasiblemethodsfor obtaining more economic and efficient flame retardants or flameretardant systems Moreover, the combining methods can be divided into chemical combination and physical compounding. Silsesquioxane-graphene compound, 13 silane-(spirocyclic pentaerythritol bisphosphorate)-phosphaphenanthrene compound, 14 and fullerene-(bicyclicpentaerythritol phosphate) compound 15 have been constructed by chemical combination to separately enhance the flame retardancy of polycarbonate and ethylene vinyl acetate copolymers. Meanwhile, by physical compounding, aluminum hypophosphite/melamine cyanurate (MCA), 16 aluminum diethyl phosphinate/mca, 17 aluminum dipropyl phosphinate/melamine, 18 and ammonium polyphosphate (APP)/melamine polyphosphate/ titanium dioxide 19 composites have been applied to the preparation of flame-retardant poly(ethylene terephthalate), poly(1,4-butylene terephthalate), polyamide 6, and poly(methyl methacrylate), respectively. APP/ethylenediamine-(N,N-diphenyl triazine), 20 APP/hyperbranched ethane diamine triazine, 21 and melamine pyrophosphate/ diethylenetriamine (ethanolamine triazine) 22 composites have been used to improve the flame retardancy of polypropylene. Similarly, APP/hyperbranched (aromatic diamine) triazine 23 composites have also imposed excellent flame retardancy to acrylonitrile butadiene styrene resin. As the fundamental materials in the electrical and electronics industries, epoxy resins need to have their flame retardancy improved either by chemical combination or physical compounding modification Several highly efficient flame retardants with bigroup or multigroup compounds have been designed and synthesized by chemical combination; examples include VC 2015 Wiley Periodicals, Inc (1 of 8) J. APPL. POLYM. SCI. 2016, DOI: /APP.43241

34 Polymer Degradation and Stability 133 (2016) 350e357 Contents lists available at ScienceDirect Polymer Degradation and Stability journal homepage: Gas-phase flame-retardant effects of a bi-group compound based on phosphaphenanthrene and triazine-trione groups in epoxy resin Shuo Tang a, b, Lijun Qian b, *, Xinxin Liu b, Yuping Dong a School of Materials, Beijing Institute of Technology, Beijing , PR China b School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, Beijing , PR China a, ** article info abstract Article history: Received 7 July 2016 Received in revised form 22 August 2016 Accepted 11 September 2016 Available online 16 September 2016 Keywords: Flame retardant Triazine-trione DOPO Epoxy Synergistic effect A flame retardant TAD constructed by phosphaphenanthrene and triazine-trione groups was synthesized via addition reaction between triallyl isocyanurate (TAIC) and 9,10-dihydro-9-oxa-10- phosphaphenanthrene-10-oxide (DOPO). Then, the molecular structure and thermal stability of TAD were characterized. To research its flame-retardant behaviors, TAD was incorporated into epoxy resin, diglycidyl ether of bisphenol-a, cured by 4,4 0 -diamino-diphenyl sulfone (DDS). TAD obviously increased the LOI values and UL94 rating of epoxy resin thermosets. TAD also reduced the values including peak of heat release rate (pk-hrr), total heat release (THR), average effective heat of combustion (av-ehc), average CO 2 yield and total mass loss (TML), and increased average CO yields of epoxy thermosets. Further, the different decrease ratio of av-ehc and TML from thermoset containing TAD reveals that TAD exerted more gas-phase flame-retardant effect than condensed-phase effect. The opinion also was testified by the TAD/EP residues with loosen morphology from the cone calorimeter test. The analyzed pyrolysis route of TAD reveals that phosphaphenanthrene group mainly exerted quenching effect and the triazine-trione group exerted gas dilution effect. The excellent flame-retardant performance of TAD is resulted by the group synergistic effect from the two typical flame-retardant groups: phosphaphenanthrene and triazine-trione Elsevier Ltd. All rights reserved. 1. Introduction Epoxy resins have been taken extensively into application for several decades. For its outstanding electrical insulation, corrosion resistance and adhesive properties [1e5], epoxy resins were widely applied in various industry fields such as electronic and electrical industry, adhesive, surface coating and painting materials and so on [6e11]. Unfortunately, inherent combustibility of epoxy impedes their wider utilization [12e15]. In its application in most irreplaceable areas, excellent flame-retardant properties are necessary for epoxy resins. 9,10-Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and its derivatives are the most common flame retardant * Corresponding author. School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, No.11, Fucheng Road, Haidian District, Beijing , PR China. ** Corresponding author. School of Materials, Beijing Institute of Technology, 5 South Zhongguancun Street, Haidian District, Beijing , PR China. addresses: qianlj@th.btbu.edu.cn, qianbtbu@163.com (L. Qian), chdongyp@bit.edu.cn (Y. Dong). agents for epoxy resins due to its dramatic flame-retardant effect [16e20]. They can exert flame-retardant effect both in gas phase and condensed phase through releasing free radicals and charring [21e24]. The free radicals released by DOPO such as PO 2 and PO quench the free radicals from burning cured epoxy resins [25,26], and further terminate the combustion chain reaction. To obtain more efficient flame-retardant epoxy resins, plenty of DOPO derivatives were synthesized through combining phosphaphenanthrene and other flame-retardant groups such as triazine [27], pentaerythritol [28], diphosphonate [18], silsesquioxane [29], schiff-base [30], or hexachlorocyclotriphosphazene [31]. Since triazine-based flame retardants such as melamine cyanurate (MCA) and melamine polyphosphate (MPP) perform good flame-retardant properties by releasing inert gases and promoting the charring effect [32,33], some derivatives containing both phosphaphenanthrene and triazine endowed epoxy resins with outstanding flame retardancy due to the group synergistic effect between the two groups [34,35]. Previous works reveal that DOPO derivatives synthesized from phosphaphenanthrene and 1,3,5-triglycidyl isocyanurate exhibited great flame-retardant effect to both diglycidyl ether of bisphenol-a(dgeba)/4,4 0 - diamino-diphenyl sulfone / 2016 Elsevier Ltd. All rights reserved.

35 Polymer Degradation and Stability 130 (2016) 173e181 Contents lists available at ScienceDirect Polymer Degradation and Stability journal homepage: Synergistic flame-retardant behavior and mechanisms of aluminum poly-hexamethylenephosphinate and phosphaphenanthrene in epoxy resin Jingyu Wang, Lijun Qian *, Zhigang Huang, Youyou Fang, Yong Qiu School of Materials Science & Mechanical Engineering, Beijing Technology and Business University, Beijing , PR China article info abstract Article history: Received 29 April 2016 Received in revised form 6 June 2016 Accepted 13 June 2016 Available online 15 June 2016 Keywords: Flame retardant Phosphinate DOPO Synergistic effect Epoxy resin The flame retardants aluminum poly-hexamethylenephosphinate (APHP) and 9,10-dihydro-9-oxa-10- phosphaphenanthrene 10-oxide(DOPO) were incorporated into diglycidyl ether of bisphenol A (EP) thermoset, and then the synergistic flame-retardant behavior and mechanism of APHP/DOPO were investigated. Comparing with the thermosets with 6%APHP and 6%DOPO alone, 2%APHP/4%DOPO/EP thermosets obtained the higher limited oxygen index, higher UL94 rating, decreased peak of heat release rate and less total heat release from cone calorimeter test. The results reveal a synergistic effect between APHP and DOPO. The synergistic effect of APHP/DOPO in gaseous phase obviously reduced effective heat of combustion, which implies the better flame inhibition effect through quenching free radical chain reaction of combustion. The synergistic charring effect in condensed phase led to the higher char yield, which locked more carbonaceous contents in residue and form more barrier to heat spreading. All the results were caused by the early decomposed DOPO that interacted with the later decomposed APHP to produce more char and decease release of the inflammable gas. Therefore, the burning intensity of APHP/ DOPO thermosets obviously was weakened by the synergistic effect of APHP/DOPO Elsevier Ltd. All rights reserved. 1. Introduction In the past several decades, flame-retardant epoxy resins have become important advanced materials in electronic and electrical equipment industries due to their excellent adhering, physicalmechanical, electric, and flame-retardant properties [1e6]. Therefore, they are widely applied as binders in printed circuit boards and as packaging materials in light-emitting diode illuminators [7e12]. To enhance flame-retardant efficiency and comprehensive properties of epoxy resins, a series of novel flame retardants especially for phosphorus-based flame retardants were prepared and incorporated into epoxy resins because of their halogen-free and high flame retardancy properties [13e19]. Among these flame retardants, some reactive and additive phosphorus flame retardants are the most important ones [20e29]. As an important reactive phosphorus flame retardant, 9,10- dihydro-9-oxa-10-phosphaphenanthrene 10-oxide(DOPO) was * Corresponding author. Gengyun Building No.516, Fucheng Road No.33, Haidian District, Beijing, PR China. address: qianlj@th.btbu.edu.cn (L. Qian). widely used to react with epoxy resin to prepare flame-retardant thermosets and also introduced into curing agent to obtain flame-retardant curing system [20,30,31]. Recently, most of the studies about DOPO have focused on the novel additives constructed by phosphaphenanthrene and several functional groups such as cyclotriphosphazene [14,32], silsesquioxane [33], triazene [16,34,35], and other groups [36e38]. These additives can endow epoxy resin thermosets by high flame retardancy, and confirm flame-retardant group synergistic effect between DOPO and other functional groups by constructing novel molecules. Though the studies on constructing DOPO-based additives have made progress on developing novel and various high efficiency flame retardants, it is still essential to explore the flame-retardant behavior of composites because it has access to seek for flame-retardant epoxy resin thermosets with higher performance [23,39e43]. Recently, a novel alkyl-phosphinate flame retardant, aluminum poly-hexamethylenephosphinate (APHP, Scheme 1), was prepared in our laboratory [44]. In former study, APHP can endow diglycidyl ether of bisphenol A (EP) thermosets with better flame retardancy in both condensed and gas phase. But the APHP/EP thermosets still failed to V-0 rating. In this study, we applied APHP into a diglycidyl / 2016 Elsevier Ltd. All rights reserved.

36 Polymer Degradation and Stability 129 (2016) 133e141 Contents lists available at ScienceDirect Polymer Degradation and Stability journal homepage: Phosphorus-nitrogen containing polymer wrapped carbon nanotubes and their flame-retardant effect on epoxy resin Shijun Wang a, Fei Xin a, *, Yu Chen b, Lijun Qian a, Yajun Chen a a Department of Materials Science & Engineering, Beijing Technology and Business University, Beijing , PR China b Beijing Huateng Hightech Co.,Ltd., Beijing , PR China article info abstract Article history: Received 22 January 2016 Received in revised form 23 March 2016 Accepted 10 April 2016 Available online 20 April 2016 Keywords: Carbon nanotubes Flame retardant Epoxy resin A novel phosphorus-nitrogen containing polymer wrapped carbon nanotubes (CNT-PD-x, x denoted the feed ratio) were facilely prepared via strong p-p stacking interactions between the poly(- phenylphosphonic-4,4 -diaminodiphenyl-methane) (PD) and the walls of carbon nanotubes (CNTs). The content of polymer PD of CNT-PD-x can be controlled by adjusting the feed ratio of polymer monomers to CNTs. The structure and properties of CNT-PD-x were characterized by Fourier transformed infrared (FT- IR) spectroscopy, 1 H nuclear magnetic resonance ( 1 H NMR), transmission electron microscopy (TEM) and thermo gravimetric analysis (TGA) measurements. The CNT-PD-x was incorporated into epoxy resin for improving the flame retardancy. The LOI value reached to 33.6% when the mass fraction of CNT-PD-x (x ¼ 20) was 4 wt%. Compared with CNTs, the same addition of CNT-PD-x (x ¼ 10) reduced the PHRR and THR of epoxy resin more effectively. The results implied the gas-condensed phase flame-retardant effect of CNT-PD-x, which is ascribed to the combined action of the polymer PD and CNTs on the flame retardancy of epoxy resin Elsevier Ltd. All rights reserved. 1. Introduction Epoxy resins (EP) have been industrialized for about 60 years and are widely used in various practical applications, especially as structural adhesive, protective coating and electrical encapsulation material due to their remarkable adhesion to many substrates, low shrinkage on cure, excellent mechanical properties and corrosion resistance [1e5]. However, epoxy resins have low flame retardancy that limits their high-performance applications for safety consideration [6]. Thus, it is important to improve the flame retardancy of epoxy resins. Currently, research on flame-retardant epoxy resins have focused on three ways, direct incorporating flame-retardant additives [7,8], building inherent flame-retardant epoxy resin molecules [9,10] and building flame-retardant curing agents of epoxy resin [11,12]. To obtain a highly efficient flame-retardant epoxy resin, the syntheses of some phosphorus-nitrogen containing flame retardants have already been conducted, such as hexa-(phosphaphenanthrene-hydroxyl-methyl-phenoxyl)-cyclotriphosphazene * Corresponding author. Gengyun Building No.9906, Fucheng Road No.11, Haidian District, Beijing, PR China. Tel.: þ address: xinfei@th.btbu.edu.cn (F. Xin). (HAP-DOPO) [13,14], tri-(3-dopo-2-hydroxypropan-1-yl)-1,3,5- triazine-2,4,6-trione (TGIC-DOPO) [15,16], poly(melamineethoxyphosphinyl-diisocyanate) (PMPC) [17] and 1,3,5-tris(2- DOPO-10-ethyl)1,3,5-triazine-2,4,6(1H,3H,5H)-trione (DOP-Cy) [18]. Moreover, carbon nanotubes (CNTs) have drawn intensive interest and are considered to be a promising candidate for improving the flame retardancy of polymer in recent decades [19e22]. The improvement of flame retardancy is attributed to the formation of network char layer created by decomposition of CNTs which can hinder the heat and mass transport [23,24]. However, the flame retardancy efficiency of the CNTs is closely related to its dispersion in the polymeric matrix [25]. Much effort has been devoted to improve the dispersibility of the CNTs through covalent and non-covalent functionalization. For instance, Fang et al. prepared intumescent flame retardant covalently grafted CNTs, which showed better dispersion and flame-retardant effect [26,27]. Molybdenum-phenolic resin was grafted onto the surface of CNTs, which improved the dispersion of CNTs in epoxy resin and showed high char yield during combustion [28]. CNTs wrapped with MoS 2 nanolayers were well-dispersed in the EP matrix, leading to simultaneous improvement of flame retardancy and mechanical properties [29]. Although many functionalized methods have been reported, the high-performance CNTs are still necessary to be / 2016 Elsevier Ltd. All rights reserved.

37 Polymer Degradation and Stability 130 (2016) 97e102 Contents lists available at ScienceDirect Polymer Degradation and Stability journal homepage: Continuous flame-retardant actions of two phosphate esters with expandable graphite in rigid polyurethane foams Wang Xi, Lijun Qian *, Zhigang Huang, Yanfang Cao, Linjie Li School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, Beijing , PR China article info abstract Article history: Received 15 April 2016 Received in revised form 3 June 2016 Accepted 5 June 2016 Available online 6 June 2016 Keywords: Flame retardant Polyurethane foams EG Phosphate ester The flame-retardant rigid polyurethane foams (RPUFs) with dimethyl methylphosphonate (DMMP)/ [bis(2-hydroxyethyl)amino]-methyl-phosphonic acid dimethyl ester (BH)/expandable graphite (EG) were prepared by box foaming. The DMMP/BH/EG flame-retardant system with certain components ratio increased the LOI value, decreased the peak value of heat release rate, sustained the effective heat of combustion and total heat release in low level, and promote the formation of phosphorus-rich compact char layer comparing with DMMP/EG and BH/EG systems. The results imply that DMMP/BH/EG possessed the trinary synergistic flame-retardant effect. The results from thermogravimetric analysis (TGA) and TGA-gas chromatography-mass spectrometer (TGA-GC-MS) all confirmed that the trinary synergistic effect of DMMP/BH/EG was caused by the continuous release of DMMP/EG and BH/EG flameretardant actions with increasing temperature. DMMP/EG and BH/EG in sequence worked in inhibiting flame and forming phosphorus-rich char layer, thus forming stable flame-retardant action on matrix and endowing RPUFs with the increased flame-retardant performance Elsevier Ltd. All rights reserved. 1. Introduction * Corresponding author. School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, No.11, Fucheng Road, Haidian District, Beijing , PR China. addresses: qianlj@th.btbu.edu.cn, qianbtbu@163.com (L. Qian). Rigid polyurethane foams (RPUFs) have widespread application as thermal insulating materials in a variety of consumer and commercial products, such as building, oil pipeline, so on. RPUFs have many excellent properties, which include superior mechanical properties and refrigerated devices and low density, especially, a low coefficient of thermal conductivity [1e5]. However, RPUFs are very combustible materials with fast flame spread and high heat release rates. In case of fire, PU foams release not only large amounts of heat but also toxic gases such as HCN and CO [6,7]. Therefore, to research flame-retardant RPUFs is very necessary [8e10]. In recent years, flame-retardant treatment for RPUFs includes the incorporation of flame retardant additive base on phosphorus, nitrogen, halogen or inorganic compounds [11e13]. Due to the less health hazard, the flame retardants containing phosphorus/nitrogen applied in RPUF have received more attentions. According to the previous literature, some researchers used a lot of additiontype flame retardants, such as phosphaphenanthrenephosphonamidates(edab-dopo) [14], ammonium polyphosphate (APP) [15,16], polydopamine (PDA) [17], expandable graphite (EG) [18e20], polyhedral oligomeric silsesquioxane (POSS) [21], triphenylphosphate (TPP) [22], dimethyl methylphosphonate (DMMP) [23e25], dimethylpropanphosphonate (DMPP) [26], hexaphenoxy-cyclotriphosphazene (HPCP) [27] and aluminium phosphinate [28]. They all can enhance the flame retardancy of RPUFs. Graft-reaction type flame retardants can be instead of polyether polyols to be incorporated into PU matrix. There are also many researcher using reaction-type flame retardants in RPUFs, Such as [bis(2-hydroxyethyl)amino]-methyl-phosphonic acid dimethyl ester (BH) [29], phosphorylated soybean oil [30], and phosphorylated polyols [31]. In recent years, EG was widely used in RPUFs as an excellent flame retardant, which can impose excellent flame-retardant effect to RPUFs in condensed phase [32,33]. The flame-retardant mechanism of EG is that EG can rapidly expand with a large ratio because the graphite slice exfoliate and curl when EG is rapidly heated. The expanded graphite can cover on matrix surface to block the heat transfer to inner matrix. However, EG also have some disadvantages in practical production. On the one hand, incorporating more EG will increase the matrix viscosity so that EG will block plug nozzle, which will lead to breaking production. Therefore, / 2016 Elsevier Ltd. All rights reserved.

38 RSC Advances PAPER View Article Online View Journal View Issue Published on 10 June Downloaded by BUSINESS COLLEGE OF BEIJING on 27/03/ :28:41. Cite this: RSC Adv., 2016,6, Received 26th April 2016 Accepted 6th June 2016 DOI: /c6ra10752d 1. Introduction Flame-retardant effect of a novel phosphaphenanthrene/triazine-trione bi-group compound on an epoxy thermoset and its pyrolysis behaviour Yong Qiu, ab Lijun Qian* a and Wang Xi a The epoxy resin industry has developed a large variety of manufactured epoxy resin products with diversiform functions, since the rst industrial production of bisphenol A epichlorohydrin epoxy resin was conducted by Devoe & Raynolds Co. in ,2 Due to their outstanding interface adhesion, 3 sealing, 4 corrosion resistance, 5 electrical insulating, 6 and mechanical performances, 7 various epoxy resin products have been widely applied in many industries, such as adhesives, 8 coatings, 9 sealants, 10 and composite structural components, 11 etc. In recent decades, with the rapid development and extensive application of polymer materials, their potential re risk has aroused more and more attention As a typical polymer material, the ammable epoxy thermoset is also trapped in this problem in particular. 17,18 The ame retarding of epoxy thermoset is the key to solve this problem. a School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, Beijing , PR China. qianlj@th.btbu.edu.cn b National Laboratory of Flame Retardant Materials, School of Materials Science and Engineering, Beijing Institute of Technology, 5 South Zhongguancun Street, Beijing , China A novel phosphaphenanthrene/triazine-trione bi-group flame retardant TOD containing two different chemical bridge bonds between phosphaphenanthrene and triazine-trione groups was synthesized through the addition reaction of 1,3,5-triglycidyl isocyanurate (TGIC), 9,10-dihydro- 9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and 10-(2,5-dihydroxyphenyl)-10-H-9-oxa-10- phosphaphenanthrene-10-oxide (ODOPB) three raw materials in turn. TOD was then applied to prepare the flame-retardant epoxy thermoset in the diglycidyl ether of bisphenol-a cured with 4,4 0 - diamino-diphenyl methane (EP). By a limited oxygen index (LOI) measurement, UL94 vertical burning test and cone calorimeter test, TOD was observed to efficiently endow the EP thermoset with a higher LOI value, higher UL94 rating, and reduced total heat release in combustion. The introduction of 4 wt% TOD endowed the EP thermoset with a LOI value of 35.9%, UL94 V-0 rating, 42.4% decreased peak of heat release rate, 46.5% decreased total heat release, and slightly elevated char yields. The analyses of the thermal and combustion behaviors of the epoxy thermoset as well as the pyrolysis behavior of TOD together revealed that the free radical quenching effect, inert volatile diluting effect, charring effect, and char layer barrier jointly caused the high-efficiency flame retardant mechanism of TOD in the epoxy thermoset. This suggests a possibility to further improve the flame retardant efficiency of bi- or multi-group compounds by selecting proper bridge-linking between functional groups. In the lasted decades, researchers have conducted a great deal of research to improve the ame-retardant performance of epoxy thermoset In previous researches, constructing novel ame retardant molecular by chemically combining known efficient characteristic structures or functional groups together was proved to be one of the most feasible methods to obtain cost-effective ame retardant compound The application results of many bi-group compounds synthesized by this method also provided many strong evidences for its rationality and scienticity, such as phosphaphenanthrene/phosphazene, 27 maleimide/phosphazene, 28 alkyl-phosphate/phosphazene, 29 alkyl-phosphate/triazine, 30 phosphaphenanthrene/ silsesquioxane, 31 phosphaphenanthrene/spirocyclic-pentaerythritol-bisphosphorate, 32 and phosphaphenanthrene/triazine, 33 etc. Hence, a new conjecture is postulated. Namely, proper chemical bridge bonds, linking different characteristic structures or groups, potentially benet to endow bi-group or multigroup compound with higher ame-retardant efficiency, resulting from the changed and even optimized pyrolysis route of ame retardant structures or groups In this work, to adjust the pyrolysis route of phosphaphenanthrene and increase additional source of phenoxy RSC Adv., 2016,6, This journal is The Royal Society of Chemistry 2016

39 Journal of Analytical and Applied Pyrolysis 127 (2017) Contents lists available at ScienceDirect Journal of Analytical and Applied Pyrolysis journal homepage: Pyrolysis and flame retardant behavior of a novel compound with multiple phosphaphenanthrene groups in epoxy thermosets Yong Qiu a,b, Zhen Liu b, Lijun Qian b,, Jianwei Hao a, MARK a School of Materials Science and Engineering, Beijing Institute of Technology, 5 South Zhongguancun Street, Beijing , China b School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, Fucheng Road 11, Beijing , China ARTICLE INFO Keywords: DOPO Pyrolysis Flame retardant Epoxy thermoset ABSTRACT A novel flame retardant compound (TDBA) with multiple phosphaphenanthrene groups was synthesized and confirmed by chemical structural and elemental characterization. Contrastive analysis on thermal decomposition behavior showed that the two kinds of bridge bonds linking phosphaphenanthrene groups in TDBA caused a wider decomposition temperature range, contributing to inhibiting combustion in relatively longer time. The application of TDBA in epoxy thermosets suggested that, TDBA capacitated the limited oxygen index of thermosets to surpass 35% and 4 wt.% or more loadings of TDBA made 4,4 -diamino-diphenyl methane curing thermosets pass UL94 V-0 rating especially. During combustion, the incorporated TDBA induced the matrix to decompose earlier, reduced the fuels production, reduced burning intensity and inhibited the combustion reaction of fuels in gaseous phase, and promoted the charring behavior of thermosets in condensed phase. The pyrolysis of TDBA proceeded along two main directions, namely substituted phosphaphenanthrene and bisphenol-a. Through releasing massive phenolic derivatives, PO free radicals and other certain phosphoruscontaining substances, TDBA is capable to exert free radical quenching effect in gaseous phase, and to promote charring behavior to form compact residue with barrier effect on heat and fuels transportation in condensed phase. This bi-phase joint action mode from TDBA endowed epoxy thermosets with excellent flame retardancy. 1. Introduction Things should be more safety, more effective, more efficient, and more convenient (4 M) during the development of science and technology [1,2]. The flame retardant modification of combustible materials also follows this 4 M principle [3 5]. Just this principle drives the flame retardant research and industries to continuously innovate and develop in recent decades [6 10]. Especially, the optimization of the application strategy on mature flame retardant products and the sustainable development of novel flame retardant compounds and technologies under 4 M principle are always the major concern and common effort of researchers and companies in flame retardant field [11 13]. Flame retardant group is a concept regarding certain specific chemical structure with unique, distinct or just efficient flame retardant effect. In recent years, the development and study of novel group-dominating flame retardant compounds were reported frequently [14 17]. Many reported researches have verified that the synergy existing in certain groups improves the efficiency of flame retardants [18,19]. In these works, many inapplicable or application-inconvenience single-group reactive materials, including phosphaphenanthrene-containing 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) [20 22], phosphazene-containing hexachlorocyclotriphosphazene [23,24], triazine-containing cyanuric chloride [25,26], triazine-trione-containing triglycidyl isocyanurate [27] and triallyl isocyanurate [28], and siloxane-containing vinyl triethoxy silane[29] and tetravinyl-tetramethyl-cyclotetrasiloxane [30], were all reported and testified capable to serve as desirable functional constituent parts for bi- or multi-group molecules. Besides, previous researches also suggested that bonding structure of groups also influenced the effect exertion of certain group-dominating flame retardant compounds [31 33]. Hence, the study on those compounds containing one, two or more kinds of flame retardant groups with different bonding linkages is also worth further efforts. In this thesis, a novel flame retardant compound (TDBA) with multiple phosphaphenanthrene groups was synthesized and characterized. In TDBA, the four phosphaphenanthrene groups were connected with the central bisphenol-a segment averagely by two kinds of different bridge bonds which appeared alone in two reported DOPO derivatives [27,28], respectively. Then, the flame retardant effect and working mechanism of TDBA in epoxy thermosets were investigated, Corresponding authors. addresses: qianlj@th.btbu.edu.cn (L. Qian), hjw@bit.edu.cn (J. Hao). Received 11 July 2017; Received in revised form 2 September 2017; Accepted 9 September 2017 Available online 11 September / 2017 Elsevier B.V. All rights reserved.

40 Synergistic flame-retardant effect of phosphaphenanthrene derivative and aluminum diethylphosphinate in glass fiber reinforced polyamide 66 Yanfang Cao, Lijun Qian, Yajun Chen, Ze Wang School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, Beijing , People s Republic of China Correspondence to: L. Qian (E- mail: qianlj@th.btbu.edu.cn; qianbtbu@163.com) ABSTRACT: The synergistic flame-retardant (FR) effect of 1,1 0 -bis(4-hydroxyphenyl)-metheylene-bis(9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide-2-hydroxypropan-1-yl) (DPOH) and aluminum diethylphosphinate (AlPi) composites on glass fiber reinforced polyamide 66 (PA) was investigated by limiting oxygen index (LOI) tests, vertical burning (UL94) tests, and cone calorimeter tests. DPOH/AlPi system with 1:1 mass ratio increased UL94 ratings, suppressed heat release rate and increased residue yields of PA composites, and DPOH/AlPi system also imposed high LOI values and lower total heat release values to PA composites. All these results verified excellent synergistic FR effect between DPOH and AlPi. The reason of DPOH/AlPi system with higher flame-retardant efficiency was caused by the quenching effect as good as that of DPOH and also by the higher charring effect than that of AlPi. DPOH/AlPi system possesses good flame retardancy in gas phase and also the strengthened FR effect in condensed phase compared with DPOH and AlPi alone, which led to excellent synergistic FR effect between the two components DPOH and AlPi. VC 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, KEYWORDS: flame retardance; polyamides; thermal properties Received 12 January 2017; accepted 19 March 2017 DOI: /app INTRODUCTION Polyamide 66 (PA) is an engineering thermoplastic, which possesses advantages of excellent mechanical performance, low frictional coefficient, fine chemical resistance, and satisfying electric property. 1 3 Thus, it has been widely applied to many aspects, such as electronics, household appliance, automobile, and aviation industry. 4 7 However, pure PA material is flammable, and it generates a lot of melt dripping and smoke during combustion. Moreover, as a result of the candle wicking effect, glass fiber reinforced PA material has worse flame retardancy with relatively low limiting oxygen index (LOI; about 23%) and no rating in UL94 test. 8,9 In order to enlarge the application of PA, it is an urgent task to develop effective flame-retardant (FR) system. In the last decades, studies on free-halogen FRs for PA have become a focus to avoid environment problems. 10,11 At the moment, phosphorous and phosphorus-nitrogen FRs are usually used in PA, such as aluminum diethylphosphinate (AlPi), melamine polyphosphate (MPP), 12,13 melamine cyanurate, 14 N-benzoic acid (ethyl-n-benzoic acid formamide) phosphamide, 15 and red phosphorus, 16 which can weaken or solve the melt dripping problem of PA during combustion. On the other hand, because of good thermal stability and non-volatile properties, inorganic filler retardants have also been added into PA to investigate the FR effect in the previous studies of academy and industry, such as montmorillonite 17 and silica nanocomposites. 18 AlPi is a favorable free-halogen organic phosphorous FR. 19,20 Many researches have revealed FR mechanism of AlPi, and it has been widely used in PA and other thermoplastics. 21,22 However, developing efficient synergist systems are still needed for less loading in PA, and many synergistic FR systems have been explored. Some inorganic nanometer FR have been used as synergist of AlPi, such as sepiolite 23 and nanosilica, 24 which can promote AlPi/PA to form the sufficient and homogeneous char layer on materials surface and improved FR properties. MPP 25 is added into AlPi/PA composite as a FR which is based on a fuel-dilution effect and phosphate barrier effect. Metal salts of ZnS 26 and ZnB 27 are also efficient synergists of AlPi for PA material. Except the improved flame retardancy, high-efficient FR synergistic system can endow PA with excellent mechanical performance for less FR loading amount. 28,29 VC 2017 Wiley Periodicals, Inc (1 of 8) J. APPL. POLYM. SCI. 2017, DOI: /APP.45126

41 Research Article Received: 24 November 2016 Revised: 2 January 2017 Accepted article published: 5 January 2017 Published online in Wiley Online Library: 14 February 2017 (wileyonlinelibrary.com) DOI /pi.5320 Synergistic barrier flame-retardant effect of aluminium poly-hexamethylenephosphinate and bisphenol-a bis(diphenyl phosphate) in epoxy resin Youyou Fang, Lijun Qian * and Zhigang Huang Abstract Two flame retardants, aluminium poly-hexamethylenephosphinate (APHP) and bisphenol-a bis(diphenyl phosphate) (BDP), were incorporated into diglycidyl ether of bisphenol A (DGEBA) thermoset with 4,4 -diaminodiphenyl sulfone (DDS) as curing agent, and then the synergistic flame-retardant behaviors of the cured thermosets were investigated. Compared with thermosets containing 10 wt% APHP and 10 wt% BDP alone, the sample with 3.3 wt% APHP and 6.7 wt% BDP (3.3%APHP/6.7%BDP/EP; EP is DGEBA/DDS) possessed a better flame-retardant effect since its limited oxygen index reached 35.0% and in the UL94 test it passed the V-0 rating. The cone calorimeter test revealed that the 3.3%APHP/6.7%BDP/EP sample generated less gaseous fragments and more smoke particles instead of fuels and verified that APHP and BDP exhibited an outstanding synergistic effect on the barrier effect. Macroscopic digital photos and micrographs from scanning electron microscopy further disclose that BDP facilitated the formation of a flexible film covering holes in the residue. The flexible film was combined with aluminium phosphate particles which were produced by decomposed APHP, thereby forming a char layer with increased barrier effect. The synergistic barrier effect from APHP and BDP imposed a better flame-retardant performance for epoxy thermosets Society of Chemical Industry Keywords: flame retardant; phosphinate; synergistic effect; epoxy resin INTRODUCTION Epoxy resins have been used extensively in applications in various industrial fields such as the electronics and electrical industry, adhesives, surface coating and painting materials and so on, for their outstanding electrical insulation, corrosion resistance, and good physical-mechanical and adhesive properties. 1,2 Unfortunately, the inherent combustibility of epoxy impedes their wider utilization, because epoxy resin is very easy to ignite and hard to extinguish. In most application fields, excellent flame-retardant properties are often necessary for epoxy resins. 3 5 Normally, phosphorus (P) based flame retardants, such as organic phosphates, alkyl-substituted phosphinates, phosphaphenanthrenes and P-containing silsesquioxanes, 6 10 can endow epoxy resins with good flame retardancy. Alkyl-substituted phosphinates were first prepared and commercialized by Clariant, and they were found to work well in polymeric materials such as polyamides, polyesters and epoxy resins Alkyl-substituted phosphinates often exert a flame-retardant effect by promoting char formation of polymeric materials and releasing a quenching effect Oligomeric phosphates including resorcinol bis(diphenyl phosphate), bisphenol-a bis(diphenyl phosphate) (BDP) and hydroquinone bis(diphenyl) phosphate are commercial flame retardants for thermoplastics and are widely applied in flame-retardant polymers BDP exerts a flame-retardant effect not only through a flame inhibition effect in the gaseous phase but also through an increased charring effect in the condensed phase. 25 BDP can raise residue yields and induce crosslinking or also react with other components to form crosslinking networks. 26 Importantly, according to previous literature BDP can also generate a synergistic effect with other flame retardants In former studies, aluminium poly-hexamethylenephosphinate (APHP) endowed diglycidyl ether of bisphenol A (DGEBA) thermosets with better flame retardancy in both the condensed and gaseous phases. However, APHP/EP thermosets still failed to pass the UL94 V-0 rating. 15 In this study, we applied APHP and BDP to flame-retardant DGEBA cured by 4,4 -diaminodiphenyl sulfone (DDS). We hope that this APHP/BDP system can make epoxy thermosets pass the UL94 V-0 rating. After the thermosets were investigated, an increased flame retardancy and a significant synergistic barrier effect between APHP and BDP were obtained in the flame-retardant epoxy resin thermosets. In this study, a quantitative assessment of the synergistic effect of APHP and BDP was also carried out. Correspondence to: L Qian, Gengyun Building No. 516, Fucheng Road No. 11, Haidian District, Beijing, China. qianlj@th.btbu.edu.cn School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, Beijing, PR China 719 Polym Int 2017; 66: Society of Chemical Industry

42 Research Article Received: 24 June 2017 Revised: 23 August 2017 Accepted article published: 5 September 2017 Published online in Wiley Online Library: 25 September 2017 (wileyonlinelibrary.com) DOI /pi.5466 Improved flame retardancy by synergy between cyclotetrasiloxane and phosphaphenanthrene/triazine compounds in epoxy thermoset Yong Qiu, a,b Volker Wachtendorf, c Patrick Klack, c Lijun Qian, a* and Bernhard Schartel c Abstract Zhen Liu a A siloxane compound (MVC) and a bi-group phosphaphenanthrene/triazine compound (TGD) were employed in epoxy thermosets to explore high-efficiency flame retardant systems. With only 1 wt% MVC and 3 wt% TGD, an epoxy thermoset passed UL 94 V-0 rating test and achieved a limiting oxygen index value of 34.0%, exhibiting an excellent flame retardant effect. The MVC/TGD system not only decreased the peak value of heat release rate and effective heat of combustion but also imparted an improved charring ability to thermosets, thereby outstandingly reducing the flammability of 1%MVC/3%TGD/EP. Compared with the fire performance of 4%TGD/EP and 4%MVC/EP, the MVC/TGD system showed an obvious flame retardant synergistic effect, mainly depending on the general improvement of flame inhibition, charring and barrier effects of the thermoset during combustion. Evolved gas analysis combined with condensed-phase pyrolysis product analysis jointly revealed the details of the changed pyrolysis mode Society of Chemical Industry Keywords: flame retardant; epoxy resin; synergy; siloxane; DOPO; triazine INTRODUCTION To reduce the flammability of epoxy thermosets according to the demands of electronics and electrical engineering, a great number of studies have been carried out. 1 4 Several works focused on reactive flame retardants, incorporating the flame retarding unit into the thermoset network to form an intrinsically flame retardant molecular chemical structure. However, these approaches require specifically designed chemical reactions to obtain target products. 5 8 These reactive-type flame retardants usually need additional effort and more difficult exploration than addition-type ones. Therefore, the alternative addition-type approach, which directly mixes flame retardant or multicomponent flame retardant systems into epoxy resins, is a more feasible method to seek for flame retardant thermosets with high performance Efficient flame retardant systems are often achieved by exploiting the synergistic effect in certain systems comprising different typical flame retardant groups, 13,14 such as phosphaphenanthrene/phosphazene, 15 phosphazene/triazine, 16 phosphaphenanthrene/phosphonate, 17,18 phosphaphenanthrene /silsesquioxane, 19 phosphaphenanthrene/triazinetrione, 20 phosphazene/maleimide, 21 melamine/metal phosphates, 22,23 9,10- dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)/ N,N -bismaleimide-4,4 -diphenylmethane, 24 hexaphenoxy cyclotriphosphazene/melamine cyanurate (MCA), 25 aluminium hypophosphite/mca 26 and ammonium polyphosphate/ octamethyl oligomeric silsesquioxane 27 mixtures. In these researches, certain flame retardant systems containing different flame retardant groups improved the flame retardant performance of polymer materials efficiently under relatively low loading. 28,29 These results implied a flame retardant group synergistic effect. Not only can different components achieve a synergistic effect in the flame retarding of polymers, but also some typical flame retardant groups also can generate an intramolecular group synergistic effect. These groups include DOPO, triazine, 33 phosphazene, 34 cyclosiloxane 35 and phosphinate 36,37 groups. Due to the limitation of fixed group ratios in specific chemical structures, the group synergistic effect in certain compounds probably does not exert the highest flame retardant efficiency. Therefore, it is still possible to enhance their working effect by means of mixing with other compounds In the study reported here, two compounds containing different flame retardant groups were adopted to flame retard epoxy thermosets. One of them was 2,4,6,8-tetravinyl- Correspondence to: L Qian, School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, Beijing , PR China. qianlj@th.btbu.edu.cn a School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, Beijing, PR China b School of Materials Science and Engineering, Beijing Institute of Technology, Beijing, PR China c Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin, Germany Polym Int 2017; 66: Society of Chemical Industry 1883

43 RSC Advances PAPER View Article Online View Journal View Issue Open Access Article. Published on 02 October Downloaded on 01/12/ :23:42. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Cite this: RSC Adv., 2017,7, Received 28th July 2017 Accepted 15th September 2017 DOI: /c7ra08340h rsc.li/rsc-advances 1. Introduction Synergistic charring effect of triazinetrione-alkylphosphinate and phosphaphenanthrene derivatives in epoxy thermosets Youyou Fang, abc Lijun Qian, As an important thermosetting resin, epoxy resin has been widely manufactured in adhesives, coatings and sealants for various applications. It has numerous advantages such as interface adhesion, sealing, corrosion resistance, electrical insulation and mechanical performance. 1 4 However, epoxy resins with low limit oxygen index value and poor UL94 rating are ammable and do not tend to self-extinguish once ignited. Moreover, excellent ame-retardant properties are oen necessary for epoxy resins in most elds of application. Therefore, more and more attention has been aroused and the higher ame retardancy of epoxy resins has been required. 5 8 Recently, ame retardants containing the triazine group such as melamine cyanurate and melamine polyphosphate with good performance and low toxicity have been investigated. 9,10 These compounds were widely used in ame-retarding epoxy resins, polyamides and polyesters. Usually, the triazine and triazine-trione groups exert a gas dilution effect in the gaseous a School of Materials Science & Mechanical Engineering, Beijing Technology and Business University, Beijing , PR China. qianlj@th.btbu.edu.cn b Engineering Laboratory of Non-halogen Flame Retardants for Polymers, Beijing , PR China c Beijing Key Laboratory of Quality Evaluation Technology for Hygiene and Safety of Plastics, Beijing , PR China d School of Materials Science and Engineering, Beijing Institute of Technology, 5 South Zhongguancun Street, Beijing , PR China * abc Zhigang Huang, abc Shuo Tang abd and Yong Qiu abd A flame retardant tri-3-(aluminum phosphinate)-propyl-1-triazine-trione (TAHP) was synthesized via the addition reaction between triallyl isocyanurate (TAIC) and hypophosphorous acid, and the molecular structure and thermal stability of TAHP were characterized. Then, TAHP was applied to the diglycidyl ether of bisphenol A (EP) cured using 4,4 0 -diamino-diphenylmethane with another DOPO derivative TAD, and the synergistic flame-retardant behavior of TAHP/TAD and the mechanism of action were also investigated. Compared with 4% TAHP/EP and 4% TAD/EP samples, the sample with 1 wt% TAHP and 3 wt% TAD obtained an LOI value of 36.0%, passed the UL94 V-0 rating test and exhibited a decreased peak value of the heat release rate. The interaction of TAHP and TAD locked more phosphoruscontaining components in the residue and formed a phosphorus-rich char layer mixed with aluminum phosphate, which generated a synergistic charring effect between TAHP and TAD and brought a better barrier effect to the epoxy thermosets during combustion. The interaction between TAHP and TAD led to a more balanced flame retardancy in the gaseous phase and condensed phase. Therefore, the TAHP/ TAD system was able to endow epoxy thermosets with better flame retardancy than them used alone. phase. 11,12 In contrast to other typical ame-retardant groups, triazine or triazine-trione groups do not have strong ameretardant effect in polymers. However, when they are combined with other ame-retardant groups such as phosphaphenanthrenes, phosphates, and ethylpiperazines, 17 the novel ame retardants usually possess group synergistic effects and endow better ame retardancy to the polymers. Inspired by this thought, we intended to design novel triazine molecules with other ame-retardant groups Normally, phosphinate can endow epoxy resin with good ame retardancy and is widely used in polymeric materials The noted product, aluminum diethylphosphinate, was rst designed and synthetized by the Clarinet Company. 25 Moreover, the compound was rst prepared and commercialized by the Clariant Corporation, and it was found to work well in polymeric materials such as polyamides, polyesters and epoxy resins It has been proven that metal phosphinate can bring outstanding ame retardancy to engineering plastics due to its catalytic charring effect and quenching effect in both the gaseous and condensed phase Researchers oen integrate the phosphonic acid group with other functional groups and exert phosphorus-rich residues in the condensed phase This is widely used in engineering plastics such as polyamide6, polyamide66, polyethylene glycol terephthalate and polybutylene terephthalate, and has good ame-retardant effect because of its excellent thermal stability and high ame resistance In our previous study, a type of alkyl-substituted phosphinate named This journal is The Royal Society of Chemistry 2017 RSC Adv., 2017, 7,

44 RSC Advances PAPER View Article Online View Journal View Issue Open Access Article. Published on 03 November Downloaded on 01/12/ :25:12. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Cite this: RSC Adv., 2017,7, Received 8th October 2017 Accepted 30th October 2017 DOI: /c7ra11069c rsc.li/rsc-advances 1. Introduction Gaseous-phase flame retardant behavior of a multi-phosphaphenanthrene compound in a polycarbonate composite Yong Qiu, ab Zhen Liu, b Lijun Qian With the rapid development of polymer science and technology, more and more polymer materials have been used to manufacture various lightweight or other featured products in a wide range of elds. 1 6 As an important general engineering plastic, polycarbonate (PC) has also achieved great development in many manufacturing industries, including building material, automobile, electrical and electronic, and medicine industries Especially for bisphenol-a type PC, its inherent ame retardancy makes most untreated bisphenol-a type PC meet the standard of the UL94 V-2 level. 11 However, the need for higherlevel ame retardant PC materials is always the bottom-line standard of application. Therefore, to ensure and further promote the prosperous application of PC, developing novel and better ame retardant PC materials is indispensable and necessary. 12,13 In recent years, great efforts have been invested into the research of ame retardant treatments on PC materials Undoubtedly, intermingling with additive-type ame retardants is the most convenient and workable strategy to improve the ame retardancy of PC materials. 18,19 Based on this cognition, massive effective ame retardants have been developed and a National Laboratory of Flame Retardant Materials, National Engineering and Technology Research Center of Flame Retardant Materials, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing , P. R. China. hjw@bit.edu.cn b Engineering Laboratory of Non-halogen Flame Retardants for Polymers, School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, Beijing , P. R. China. qianlj@th.btbu.edu.cn * b and Jianwei Hao* a A multi-phosphaphenanthrene compound (TDBA) was incorporated into polycarbonate (PC) to prepare a flame retardant composite. TDBA improved the flame retardancy of the PC material effectively. The PC composite comprising 10 wt% TDBA passed the UL94 V-0 level with a LOI value of 33.7%. The incorporation of TDBA effectively inhibited the combustion intensity of the TDBA/PC composite via reducing the production of flammable methane and carbonyl-containing substances, suppressing the oxidative process of combustible pyrolysis products, and promoting the PC matrix to form large-scale smoke particles. All these were caused by releasing phosphaphenanthrene fragments, PO, and phenoxyl free radicals from pyrolyzed TDBA. As an additive-type flame retardant with multiple phosphaphenanthrene groups, TDBA was verified to exert its effect mainly in the gaseous phase during flame retarding of PC materials. applied in ame retarding PC materials, including halogencontaining, 20 sulphonate-containing, 21,22 organosilicon-containing, 23 phosphorus-containing compounds, 24 inorganic additives, 25 and nanomaterials. 26,27 Recently, as a promising intermediate in developing novel halogen-free ame retardants, 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide (DOPO) have been frequently used to synthesize effective and efficient phosphaphenanthrene-containing ame retardant additives for various polymer materials And some similar works have also suggested that the addition of phosphaphenanthrenecontaining additive indeed improved the ame retardancy of PC materials effectively. 34 Hence, the research on the phosphaphenanthrene-containing compound ame retarding PC materials is worth further exploring and investigating. In this thesis, an additive-type, four-arm star-shaped, and multi-phosphaphenanthrene ame retardant compound (TDBA, 35 shown in Fig. 1) is looking forward to improve the ame retardancy of PC materials effectively due to its multiple phosphaphenanthrene groups (ame retardant segment, shown in Fig. 1). The limited oxygen index (LOI) measurement, vertical burning test, and cone calorimeter test were adopted to evaluate the ammability and combustion behavior of composites. Meanwhile, the thermogravimetry-fourier transform infrared spectroscopy (TG-FTIR) analyzed the inuence of TDBA on the decomposition of PC matrix, and also monitored the structural characteristic of evolved gases during TG procedure. Furthermore, the pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) analysis on PC composites was also adopted to reveal the inuence of TDBA on the detailed pyrolysis products of PC matrix. Through above results and RSC Adv., 2017,7, This journal is The Royal Society of Chemistry 2017

45 RSC Advances PAPER View Article Online View Journal View Issue Open Access Article. Published on 03 January Downloaded on 28/03/ :24:09. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Cite this: RSC Adv., 2017,7, 720 Received 11th October 2016 Accepted 20th November 2016 DOI: /c6ra25070j 1. Introduction Epoxy resins have been used widely in many elds due to their excellent properties, such as outstanding electrical insulation, corrosion resistance, and adhesive properties. 1 4 Therefore, they are widely used as adhesives in printed circuit boards and packaging materials, and applied in other elds including surface coatings and painting materials. 5 8 Unfortunately, the ammability of epoxy resins restricts their application in the eld of ame-retarded materials To expand their application in this eld, many studies have been performed to improve the ame retardancy of epoxy resins via the addition of various ame retardants ,10-Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and its derivatives are one of the most commonly used ame retardants for epoxy resins due to their dramatic ameretardant effect They exert a ame-retardant quenching effect through the release of free PO 2 c and POc radicals and disturb the combustion chain reaction in the gas phase, as well as interacting with the decomposing polymer and inducing a School of Materials, Beijing Institute of Technology, Beijing , PR China b School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, Beijing , PR China. qianlj@th.btbu.edu.cn c Bundesanstalt für Materialforschung und prüfung (BAM), Unter den Eichen 87, Berlin, Germany. bernhard.schartel@bam.de Enhanced flame-retardant effect of a montmorillonite/phosphaphenanthrene compound in an epoxy thermoset Shuo Tang, ab Volker Wachtendorf, c Patrick Klack, c Lijun Qian,* b Yuping Dong a and Bernhard Schartel* c A phosphaphenanthrene and triazinetrione group containing flame retardant (TAD) is combined with organically modified montmorillonite (OMMT) in epoxy resin thermosets (EP) to improve the performance of the flame-retardant system. When only 1 wt% OMMT/4 wt% TAD is introduced into the EP, the limited oxygen index (LOI) rises from 26% to 36.9% and a V-0 rating is achieved in a UL 94 test. The decomposition and pyrolysis products in the gas phase and condensed phase were characterized using thermogravimetry-fourier transform infrared spectroscopy (TG-FTIR). The influence on the decomposition of EP, such as the increase in char yield, is limited with the incorporation of OMMT; a large amount of the phosphorus is released into the gas phase. The flame-retardant effect evaluation based on cone calorimeter data testified that OMMT improves the protective-barrier effect of the fire residue of OMMT/TAD/EP on the macroscopic scale, while TAD mainly causes flame inhibition. The fire residues showed a corresponding macroscopic appearance (digital photo) and microstructure (scanning electron microscope [SEM] results). The protective barrier effect of OMMT and the flame-inhibition effect of TAD combined to exert a superior flame-retardant effect, resulting in sufficient flame-retardant performance of OMMT/TAD/EP. charring in the condensed phase To further improve the ame retardant properties of epoxy resins, many kinds of DOPO derivatives containing different ame retardant groups such as triazine, 22 pentaerythritol, 23 diphosphonate, 24 silsesquioxane 25 have been synthesized and applied to ame-retardant polymeric materials. Inorganic ame retardants have frequently been applied to ame-retardant epoxy resins due to their low cost, low toxicity and high thermal stability Among them, organically modi- ed montmorillonite (OMMT) is oen chosen to improve the ame resistance and thermal properties of epoxy resins and polyamides. 29,30 As OMMT can work as a protective barrier to ame, suppress smoke 31 and act as a heat storage medium, 32 it is oen used as an adjuvant to improve ame-retardant systems. 33 In this work, a DOPO derivative with phosphaphenanthrene and triazinetrione groups, TAD, was applied in epoxy resins, and its molecular structure was shown in Fig. 1. TAD showed a good ame-retardant effect in the gas phase. To improve the ame-retardant efficiency of TAD, OMMT was incorporated into epoxy resin thermosets (EP) based on diglycidyl ether of bisphenol-a (DGEBA) and 4,4 0 -diamino-diphenyl methane (DDM), ame-retarded with TAD. OMMT was proposed to be an effective inorganic adjuvant inducing protective barrier effects. The ame retardancy of the OMMT/TAD system in EP was explored and the ame-retardant modes of action were discussed. 720 RSC Adv., 2017,7, This journal is The Royal Society of Chemistry 2017

46 Addition flame-retardant effect of nonreactive phosphonate and expandable graphite in rigid polyurethane foams Linjie Li, 1,2,3 Yajun Chen, 1,2,3 Lijun Qian, 1,2,3 Bo Xu, 1,2,3 Wang Xi 1,2 1 School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, Beijing , China 2 Engineering Laboratory of non-halogen flame retardants for polymers, Beijing , China 3 Beijing Key Laboratory of Quality Evaluation Technology for Hygiene and Safety of Plastics, Beijing , China Correspondence to: Y. Chen (E- mail: chenyajun@th.btbu.edu.cn) and L. Qian (E- mail: qianlj@th.btbu.edu.cn) ABSTRACT: A series of flame-retardant rigid polyurethane foams (RPUFs) containing nonreactive phosphonate (5-ethyl-2-methyl- 1,3,2-dioxaphosphorinan-5-yl) methyl dimethyl phosphonate P-oxide (EMD) and expandable graphite (EG) were prepared by water blown. The flame-retardant properties and mechanism of EMD/EG on RPUFs were systematically investigated. The EMD/EG system effectively increased the limiting oxygen index (LOI) value and decreased the values of total heat release (THR), av-effective heat of combustion (EHC), pk-heat release rate (HRR), total smoke release (TSR) of RPUFs. The impact values of LOI, THR, and av-ehc resulted by EMD/EG system are nearly equal to the sum of the impact values by EMD and EG individually in RPUFs, which implies the addition flame-retardant effect from EMD and EG. EMD alone exerted excellent gas-phase flame-retardant effect by releasing PO fragments with quenching effect. The firm residue produced by EMD combined well with the loose and worm-like expanded graphite from EG further to form compact and expanded char layer, which brought excellent barrier effect and filtration effect to matrix. That s why pk-hrr and TSR values of RPUF reduced. Depending on the simultaneous actions of EMD/EG system in gas phase and condensed phase during combustion, the flame-retardant effects from nonreactive phosphonate and EG on RPUFs were added together. VC 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, KEYWORDS: flame retardance; foams; polyurethane Received 21 August 2017; accepted 21 October 2017 DOI: /app INTRODUCTION Rigid polyurethane foams (RPUFs) are widely used as a kind of thermal-insulation and sealing materials in industry and daily life, attributing to its unique properties such as high strength, sound absorption function, low coefficient of thermal conductivity, water resistance, and so on. 1 7 In addition, to develop energy-saving social, that is inevitable to pay more attentions to this kind of organic thermal-insulation materials. Their high flammability in fire, however, restricts the applications in stringent fire-proof situation Hence, it is essential to impose flame-retardant properties to RPUFs by incorporating suitable flame retardant components. Great attentions have been given to phosphorus-containing compounds as flame retardants in RPUFs for a long time, considering the prominent advantages including halogen-free, low toxicity, no emission corrosive gas, and high flame retardancy. 11,12 Generally, previous studies have demonstrated that phosphorus-containing compounds can work in both gas and condensed phases. In gas phase, phosphorus-containing flame retardants can inhibit the combustion of flammable gas and hamper the free radical chain reaction of combustion through radical trapping mechanism, while in condensed phase they can promote the formation of protective char layer. 13,14 Thus, many researchers introduced a lot of phosphorus-containing flame retardants into RPUFs to enhance their flame retardancy, such as dimethyl methylphosphonate (DMMP), 15 triethyl phosphate, 16 ammonium polyphosphate, 17 pentaerythritol phosphate, 18 hexa-phenoxy-cyclotriphosphazene, 19 aluminum hypophosphite. 20 In order to obtain flame-retardant system with higher efficiency, expandable graphite (EG) also usually was applied with other additives in RPUFs due to its excellent intumescent barrier effect on fire EG can produce worm-like char layer covered on the surface of matrix to isolate heat and protect RPUF matrix. 25,26 In our previous research, 23 a reactive-type phosphonate [bis(2- hydroxyethyl)amino]-methyl-phosphonic acid dimethyl ester and EG were applied in RPUF and were found that they had an addition flame retardant effect, which enhanced dramatically the flame retardancy of RPUF matrix. In this study, a VC 2017 Wiley Periodicals, Inc (1 of 8) J. APPL. POLYM. SCI. 2018, DOI: /APP.45960

47 Flame-retardant behavior of a phosphorus/silicon compound on polycarbonate Pei Ni, 1,2,3 Youyou Fang, 1,2,3 Lijun Qian, 1,2,3 Yong Qiu 1,2,3 1 School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, Beijing , China 2 Engineering Laboratory of Nonhalogen Flame Retardants for Polymers, Beijing , China 3 Beijing Key Laboratory of Quality Evaluation Technology for Hygiene and Safety of Plastics, Beijing , China Correspondence to: L. Qian (E- mail: qianlj@th.btbu.edu.cn) ABSTRACT: A phosphorus/silicon flame retardant, MVC-DOPO, was synthesized from 9,10-dihydro-9-oxa-10-phosphaphenanthrene- 10-oxide (DOPO) and 2,4,6,8-tetra-methyl-2,4,6,8-tetra-vinyl-cyclo-tetrasiloxane (MVC) via addition reaction. Its flame-retardant effect on polycarbonate (PC) was investigated. The phosphorus/silicon flame retardant increased the limited oxygen index and UL-94 rating and reduced the heat release rate and total heat release of DOPO-MVC/PC composites during combustion, indicating the excellent flame-retardant effect of MVC-DOPO on PC. MVC-DOPO inhibited the burning intensity of PC material in the gaseous phase and promoted the formation of a more viscous residue in the condensed phase. Through releasing phosphorus-containing pieces and phenoxy radicals from the phosphaphenanthrene group, MVC-DOPO quenched the combustion chain reaction in the gaseous phase; through promoting formation of a more viscous residue and a dense char layer from the main actions of the cyclotetrasiloxane group, MVC-DOPO reduced fuel release and generated a barrier effect in the condensed phase. Hence, MVC-DOPO effectively exerted a flame-retardant effect on PC material in both the gaseous and condensed phases during combustion. VC 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, KEYWORDS: flame retardance; structure property relationships; thermal properties Received 31 July 2017; accepted 20 September 2017 DOI: /app INTRODUCTION In recent years, polymeric materials have been more and more applied in many fields. 1 Polycarbonate (PC), a kind of rapiddeveloping thermoplastic resin, is widely used as an amorphous engineering polymer in construction, medical equipment, transport, and other fields due to its outstanding properties, such as high mechanical properties, high flame retardancy, excellent electric properties, and high glass-transition temperature. 2 5 However, PC flame retardancy is often required in many fields, especially in electronic applications. Although some organic halogen compounds can provide better solutions for flameretarding PC, worries about the environmental problems of organic halogen compounds drive researchers to pay increasing attention to the more efficient halogen-free flame retardants. 6,7 It is widely known that the aromatic phosphates triphenyl phosphate (TPP), bisphenol-a-bis(di-phenyl phosphate) (BDP), and resorcinol bis-(di-phenyl phosphate) (RDP) have been used in polycarbonates. 8,9 But because the viscous liquid phosphates lack sufficient hydrolysis stability, they would cause some processing problems and decrease the heat distortion temperature of PC composites Recently, phosphonium salts have received attention because of their high thermal stability, high charring yield, and good solubility to polymers. 13,14 In these studies, cyclic phosphates, 15 phenyl phosphine oligomer, phosphonium sulfonates, and rigid steric hindering spiro-bisphosphates were all disclosed to have an excellent flame-retardant effect on PC On the other hand, silicon-containing compounds gradually attracted attention because of their environmentally friendly properties. 19,20 Most organic phosphorus/silicon compounds exhibited better flame retardancy than those containing a single element Although a series of studies have been carried out to explore the flame-retardant effect of several organic phosphorus/silicon compounds, phosphorus/silicon compounds need further work to illuminate their working mechanism and action mode Recently, a kind of novel flame retardant, 2,4,6,8-tetra-[(2- DOPO-ethylene-1-yl)-methyl]-cyclo-tetrasiloxane (MVC-DOPO), a phosphorus/silicon flame retardant, was prepared in our laboratory. Then it was incorporated into PC through melt blending, and it provided an excellent flame-retardant property to PC VC 2017 Wiley Periodicals, Inc (1 of 8) J. APPL. POLYM. SCI. 2018, DOI: /APP.45815

48 Received: 29 July 2017 Revised: 29 August 2017 Accepted: 3 September 2017 DOI: /pat.4174 RESEARCH ARTICLE Synergistic flame retardant effect and mechanisms of boron/ phosphorus compounds on epoxy resins Shuo Tang 1 Lijun Qian 2 Yong Qiu 1 Yuping Dong 1 1 Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications, School of Materials Science and Engineering, Beijing Institute of Technology, 5 South Zhongguancun Street, Beijing , China 2 School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, Beijing , China Correspondence Lijun Qian, School of Materials Science and Mechanical Engineering, BeijingTechnology and Business University, No.11, Fucheng Road, Haidian District, Beijing , China. qianlj@th.btbu.edu.cn; qianbtbu@163.com Yuping Dong, School of Materials Science and Engineering, Beijing Institute of Technology, 5 South Zhongguancun Street, Haidian District, Beijing , China. chdongyp@bit.edu.cn Funding information Plans to Upgrade Beijing Municipal Innovation Ability, Grant/Award Number: No. TJSHG TJSHG ; National Nature Science Foundation of China, Grant/AwardNumber: No To explore the component synergistic effect of boron/phosphorus compounds in epoxy resin (EP), 3 typical boron compounds, zinc borate (ZB), boron phosphate (BPO 4 ), and boron oxide (B 2 O 3 ), blended with phosphaphenanthrene compound TAD were incorporated into EP, respectively. All 3 boron/phosphorus compound systems inhibited heat release and increased residue yields and exerted smoke suppression effect. Among 3 boron/phosphorus compound systems, B 2 O 3 /TAD system brought best flame retardant effect to epoxy thermosets in improving the UL94 classification of EP composites and also reducing heat release most efficiently during combustion. B 2 O 3 can interact with epoxy matrix and enhance the charring quantity and quality, resulting in obvious condensed phase flame retardant effect. The combination of condensed phase flame retardant effect from B 2 O 3 and the gaseous phase flame retardant effect from TAD effectively optimized the action distribution between gaseous and condensed phases. Therefore, B 2 O 3 /TAD system generated component synergistic flameretardant effect in epoxy thermosets. KEYWORDS boron, DOPO, epoxy resin, flame retardant 1 INTRODUCTION Due to outstanding electrical insulation, corrosion resistance, and adhesive properties, 1-3 epoxy resins (EPs) have been widely used in electronic and electrical industries, packaging materials, and other fields including surface coatings and painting materials. 4,5 Unfortunately, the flammability of EPs severely restricts their application in the field of flame retarded materials. 6-8 To expand their application in this field, many studies have been performed to improve the flame retardancy of EPs through the addition of various flame retardants. 9,10 So far, phosphorus containing flame retardants are considered to be more environmentally friendly and have attracted more attention than halogen based flame retardants in the research field of flame retardant EPs. 11,12 Among these phosphorus containing compounds, 9,10 dihydro 9 oxa 10 phosphaphenanthrene 10 oxide (DOPO) and its derivatives are the most commonly used flame retardants for EPs due to their dramatic flame retardant efficiency They mainly exert flameretardant quenching effect through releasing free PO radicals and terminating the combustion chain reaction in gaseous phase, 16,17 as well as interacting with the decomposing polymer and increasing char yields in condensed phase. 18,19 Various kinds of DOPO derivatives were prepared through the reaction of DOPO and other flameretardant functional groups to construct high efficiency flameretardant system. Another approach to high efficient flame retardant system is to mix different flame retardants. When they were applied into EPs, usually, they endowed epoxy thermosets with remarkable flame retardancy by means of group synergistic effect or component synergistic effect In reported literatures, inorganic flame retardants have frequently been chosen to mix with other flame retardants for constructing highefficiency flame retardant system due to their low cost, low toxicity, and high thermal stability Among them, boron compounds such as zinc borate (ZB), boric acid, boron oxide (B 2 O 3 ), boron phosphate (BPO 4 ), melamine borate, and so on were often chosen to be utilized in EPs. It has been reported that boron compounds could improve the flame retardancy of EPs by increasing char yield, suppressing smoke, releasing water, and absorbing heat Polym Adv Technol. 2017;1 8. wileyonlinelibrary.com/journal/pat Copyright 2017 John Wiley & Sons, Ltd. 1

49 The Synergistic Flame-Retardant Behaviors of Pentaerythritol Phosphate and Expandable Graphite in Rigid Polyurethane Foams Shijun Wang, Lijun Qian, Fei Xin Department of Materials Science & Engineering, School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, Beijing , People s Republic of China The flame-retardant rigid polyurethane foams (RPUFs) containing pentaerythritol phosphate (PEPA) and expandable graphite (EG) were prepared by boxfoaming. The flame retardancy of RPUFs was characterized using the limiting oxygen index (LOI) and cone calorimeter. The results show that the PEPA/EG system can effectively enhance the LOI values and reduce the peak release rate of RPUFs comparing with the foams only containing PEPA or EG although the flame retardants in all the samples are same proportion. The two results imply that the PEPA/EG system form flame-retardant synergistic effect. The micromorphology and chemical structure of residues of RPUFs were also investigated by scanning electron microscope and Fourier transform-infrared instruments. During combustion, the polyphosphates and their related analogues generated by PEPA can combine with the surfaces of expanded graphite, thereby resulting in the formation of the improved char layer. The layer possessed increased barrier effect and thereby imposing the better flame retardancy to RPUFs. POLYM. COM- POS., 00: , VC 2016 Society of Plastics Engineers INTRODUCTION The polyurethane (PU) foam is a typical lightweight material, which commonly consists of polyol, isocyanate, blowing agent, catalysts, and surfactants [1]. PU foams possessed the largest global market among polymeric foams, and the rigid PU foam (RPUF) accounts for about Correspondence to: L. Qian; qianlj@th.btbu.edu.cn or augusqian@163.com Contract grant sponsor: Plans to Upgrade Beijing Municipal Innovation Ability; contract grant number: TJSHG ; contract grant sponsor: Importation and Development of High-Caliber Talents Project of Beijing Municipal Institutions; contract grant number: CIT&TCD Additional Supporting Information may be found in the online version of this article. About this article, we have never carried out oral presentation before, and original source of the material all derives from our laboratory. DOI /pc Published online in Wiley Online Library (wileyonlinelibrary.com). VC 2016 Society of Plastics Engineers 23% of all PU products [2, 3]. Moreover, RPUFs have several excellent properties including high compressive strength, high abrasion resistance, low thermal conductivity, good shock absorption, and low water absorption [4 7]. Especially, RPUF is also a good building insulation materials and has wide application in construction filed because thermal insulation plays a critical factor in controlling the energy efficiency of buildings [8]. However, as a petroleum-based polymeric insulation material, RPUF is also easily ignitable. Therefore, to impart flame retardancy to RPUF is necessary for its practical demands [9 11]. In the past years, a large number of experimental investigations on flame retardancy of RPUFs have been reported. The selection of appropriate flame retardants for RPUFs is very important. Thus, many kinds of flame retardants have been incorporated into RPUFs to enhance the flame retardancy, including dimethyl methylphosphonate (DMMP) [12, 13], hexa-phenoxy-cyclotriphosphazene (HPCP) [14], ammonium polyphosphate (APP) [15, 16], tris-(2-chloropropyl)-phosphate (TCPP) [17], triethylphosphate (TEP) [18], inorganic and organic phosphinates [19, 20], and melamine cyanurate (MC) [21]. Moreover, some researchers have adopted coating [22, 23] or impregnation [24] technology to endow RPUFs with flame retardancy. Expandable graphite (EG) is a kind of effective inorganic flame retardant for RPUFs, which has an important effect in condensed phase through the formation of an intumescent carbonaceous layer at high temperature [14]. However, the char layer of only EG-containing RPUF is loose and polycellular, and thus cannot exhibit perfect flame retardancy. In addition, the excessive addition of EG will not only makes foaming process harder but also reduces the mechanical properties of RPUFs [12]. In this study, we incorporated another flame retardant pentaerythritol phosphate (PEPA) into RPUF in order to offset the defect of EG. Besides, the PEPA can be introduced to PU molecular chains by reaction with the isocyanate, which can avoid the migration of addition-type flame retardants. The reaction formula is shown in Scheme 1. Then, the flame-retardant behaviors of RPUFs POLYMER COMPOSITES 2016

50 PROGRESS IN CHEMISTRY Vol. 22 No. 9 Sep * DOPOP H DOPO O626. 3TB324 A X Construction and Properties of Compounds Based on Phosphaphenanthrene Group Qian Lijun 1 Ye Longjian 1 Han Xinlei 1 Xu Guozhi 1 Meng Ye 2 1. Department of Materials Science & EngineeringBeijing Technology and Business UniversityBeijing China2. Shandong Ocean Chemical Industry Scientific Research InstituteWeifang China Abstract Phosphaphenanthrene group has characteristics of heterocycle containing phosphorusmolecular non-coplanarinteraction with intermolecular and intramolecular groupsmolecular polarityetc. Thereforeit can be used as a modification group to construct compounds with novel structure and properties. In this thesisthe synthesis methods of compounds based on phosphaphenanthrene groupproperties of functional materials containing phosphaphenanthrene group and the influence law of the group on properties of materials are reviewed. preparing method and mechanism of phosphaphenanthrene derivatives from reacting of P H bond of 9 10-dihydro- 9-oxa-10-phosphaphenanthrene-10-oxide with unsaturated groups including quinine bondaldehyde bondketone bondc C bondc N bond and C帒 N bonds by adding reaction are introduced. The fire retardant properties of materials containing phosphaphenanthrene group including epoxy resinspolyesterscoating and additiveand the mechanism of phosphaphenanthrene group enhancing fire retardant properties of materials are mainly summarized. Phosphaphenanthrene group can also influence liquid crystal behavior of thermal liquid crystal polymers for its interaction with intermolecular and intramolecular groupsand the interaction lead to aggregationinduced emission enhancement behavior of some compounds. Finallywe mention that the polarity of phosphaphenanthrene group can increase the molecular polarity of polyester and polyamides compoundsand make The * No. 2009EG Corresponding author qianlj@ th. btbu. edu. cn

51 Author's personal copy Polymer Degradation and Stability 96 (2011) 1118e1124 Contents lists available at ScienceDirect Polymer Degradation and Stability journal homepage: The non-halogen flame retardant epoxy resin based on a novel compound with phosphaphenanthrene and cyclotriphosphazene double functional groups Li-Jun Qian *, Long-Jian Ye, Guo-Zhi Xu, Jing Liu, Jia-Qing Guo Department of Materials Science & Engineering, Beijing Technology and Business University, Beijing , China article info abstract Article history: Received 21 November 2010 Received in revised form 18 February 2011 Accepted 4 March 2011 Available online 16 March 2011 Keywords: Cyclotriphosphazene Phosphaphenanthrene Flame retardant Epoxy resin A novel flame retardant additive hexa-(phosphaphenanthrene -hydroxyl-methyl-phenoxyl)-cyclotriphosphazene (HAPeDOPO) with phosphazene and phosphaphenanthrene double functional groups has been synthesized from hexa-chloro-cyclotriphosphazene, 4-hydroxy-benzaldehyde and 9,10-dihydro-9-oxa-10- phosphaphenanthrene 10-oxide(DOPO). The structure of HAPeDOPO was characterized by Fourier transformed infrared (FT-IR) spectroscopy and 1 H nuclear magnetic resonance ( 1 H NMR) and 31 P nuclear magnetic resonance ( 31 P NMR). The additive HAPeDOPO was blended into diglycidyl ether of bisphenol-a (DGEBA) to prepare flame retardant epoxy resins. The flame retardant properties and thermal properties of the epoxy resins cured by 4, 4 0 -Diamino-diphenyl sulfone (DDS) were investigated from the differential scanning calorimeter (DSC), the thermogravimetric analysis (TGA), UL94 test, the limiting oxygen index (LOI) test and Cone calorimeter. Compared to traditional DOPOeDGEBA and ODOPBeDGEBA thermosets, the HAPeDOPO/DGEBA thermosets have higher T g s at the same UL94 V-0 flammability rating for their higher crosslinking density and have higher char yield and lower pk-hrr at same 1.2 wt.% phosphorus content which confirm that HAPeDOPO has higher flame retardant efficiency on thermosets. The scanning electron microscopy (SEM) results shows that HAPeDOPO in DGEBA/DDS system obviously accelerate formation of the sealing, stronger and phosphorus-rich char layer to improve flame retardant properties of matrix during combustion. Ó 2011 Elsevier Ltd. All rights reserved. 1. Introduction The non-halogen flame retardant epoxy resins containing 9,10- dihydro-9-oxa-10- phosphaphenanthrene-10-oxide (DOPO) have been widely researched and a few have been applied in semiconductor encapsulants, fiber reinforced composites and printed circuit boards for its excellent flame retardancy [1e5]. Most of them is based on diglycidyl ether of bisphenol-a (DGEBA) owing to its remarkable adhering, low shrinkage on cure, good electrical and mechanical properties, and especially ease of handling and processability [6e11]. Usually, the epoxy resins containing DOPO group are prepared by the methods that PeH bond of DOPO react with epoxide group of epoxy resins by addition reaction or that DOPO derivatives react with epoxide group [11e14]. But the functionality of the flame retardant epoxy resins prepared by above methods is obviously decreased for the addition reaction of DOPO and its derivatives with epoxide groups. Consequently, it directly leads to a less crosslinking density in the cured * Corresponding author. Tel.: þ address: qianlj@th.btbu.edu.cn (L.-J. Qian). epoxy resins and the low T g s of thermosets [15]. Further, the flame retardant epoxy resins based on DOPO reach UL94 V-0 flammability rating still need a higher adding ratio of DOPO or its derivatives for their phosphorus content below 14.4 wt.% [16,17]. For more convenient application, more excellent flame retardant performance and more outstanding physicalemechanical properties, it is necessary to explore an unreactive way of utilizing DOPO which can preserve the functionality of resins for more excellent physicalemechanical properties. The cyclotriphosphazene compounds, which have been attention for its excellent thermal and charring properties, can provide improved flame retardant properties to polymers and their composites [18e22]. We tend to integrate phosphaphenanthrene and cyclotrphosphazene groups into one molecule as flame retardant additive instead of reactive DOPO and its derivatives in epoxy resin thermosets. In this work, we synthesized a novel-structure additive hexa- (phosphaphenanthrene- hydroxyl-methyl-phenoxyl)ecyclotriphos phazene (HAPeDOPO) derived from DOPO, 4-hydroxy-benzaldehyde and hexa-chloro-cyclotriphosphazene. The additive is also mixed into DGEBA to prepare non-halogen flame retardant epoxy resins and then the flame retardant properties and mechanism of cured epoxy resins are characterized and disclosed. We also explore /$ e see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi: /j.polymdegradstab

52 Polymer 52 (2011) 5486e5493 Contents lists available at SciVerse ScienceDirect Polymer journal homepage: Thermal degradation behavior of the compound containing phosphaphenanthrene and phosphazene groups and its flame retardant mechanism on epoxy resin Lijun Qian *, Longjian Ye, Yong Qiu, Shuren Qu Department of Materials Science & Engineering, Beijing Technology and Business University, Beijing , PR China article info abstract Article history: Received 3 August 2011 Received in revised form 6 September 2011 Accepted 29 September 2011 Available online 6 October 2011 Keywords: Flame retardant Structure-effect DOPO The flame retardant epoxy resin has been prepared by mixing the flame retardant additive hexa- (phosphaphenanthrene-hydroxyl-methyl-phenoxyl)-cyclotriphosphazene (HAP-DOPO) into diglycidyl ether of bisphenol-a (DGEBA). After cured by 4,4 0 -Diamino-diphenyl sulfone (DDS), the flame retardant properties of thermosets were characterized by the limited oxygen index (LOI), UL-94 test and cone calorimeter. The results show the lower peak of heat release rate (pk-hrr), the higher flammability rating than that of flame retardant epoxy resin by 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10- oxide (DOPO), hexa-phenoxyl-cyclotriphosphazene (HPCP) and their mixture cloning the ratio of group component of HAP-DOPO. The degradation route of HAP-DOPO was disclosed by thermogravimetric analysis (TGA), the real time Fourier transform infrared spectra (FTIR), thermogravimetric analysis/infrared spectrometry (TGA-FTIR), pyrolysis gas chromatography mass/spectrometry (Py-GC/MS). During combustion, HAP-DOPO continues to release the PO radicals and o-phenylphenoxyl radical during two degradation stages from 200 C for its unstable trisubstituted methyl structure of HAP-DOPO, inhibits the chain reaction of decomposition and exerts the flame retardant effect in gas phase. The phosphazene groups link with the residual phosphate from degraded phosphaphenanthrene, which increases the crosslink density of residue, effectively promotes the formation of high-strength, high-yield and phosphorus-rich char layer. The structure of HAP-DOPO shows a remarkable flame retardant molecular structure-effect on enhancing the flame retardant efficiency on thermosets. Ó 2011 Elsevier Ltd. All rights reserved. 1. Introduction Epoxy resins have been widely used as matrix resin for structural compositions and electronic parts due to its ease of handling and processability, low shrinkage on cure, superior electrical and mechanical properties, and remarkable adhesion to many substrates [1e5]. However, the matrix resin is difficult to meet those high heat resistance and flame retardant fields and applications. Many methods have been developed to improve its thermal stability and flame retardancy [6e10]. In recent years, 9,10-dihydro-9-oxa-10-phosphaphenanthrene- 10-oxide (DOPO) and its derivatives have received outstanding attention because of their high reactivity and applicability on epoxy resin [8]. The works reported for halogen-free flame retardant epoxy resins based on DOPO mainly include the multi-flameretardant-group epoxy resins [11e14], the novel structure epoxy * Corresponding author. Tel.: þ ; fax: þ86 (0) address: qianbtbu@163.com (L. Qian). resins [15,16], the high T g epoxy resin [17,18], epoxy resin composition [19,20] and DOPO-modified curing agents [2,21,22]. Although a lot of researches have been carried out, some considerable question still need to be explored, such as how to increase flame retardant efficiency of the functional groups and that what kind of molecular structure of flame materials can contribute more to the flame retardant efficiency of materials. Therefore, it is necessary to explore the degradation route and the pyrolysis behavior of flame retardant materials [23,24]. Fortunately, a few works has been reported about the pyrolysis mechanism of DOPO-containing polymers [1,12,25,26]. Recently, we attempt to construct the additive molecule with double functional groups for obtaining flame retardant materials with high efficiency. We integrated phosphaphenanthrene and cyclotriphosphazene groups into one molecule as flame retardant additive instead of the reactive DOPO, phosphazene compounds and their derivatives in thermosets. It directly leads to a higher T g and perfect flame retardancy of thermosets with a lower addition [14]. However, the molecular degradation and flame retardant mechanisms are still undisclosed in the former research /$ e see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi: /j.polymer

53 The Flame Retardant Group-Synergistic-Effect of a Phosphaphenanthrene and Triazine Double-Group Compound in Epoxy Resin Lijun Qian, Yong Qiu, Jing Liu, Fei Xin, Yajun Chen Department of Materials Science & Engineering, Beijing Technology and Business University, Beijing , People s Republic of China Correspondence to: L. Qian (E- mail: qianlj@th.btbu.edu.cn) ABSTRACT: A flame retardant tri-(phosphaphenanthrene-(hydroxyl-methylene)-phenoxyl)-1, 3, 5-triazine (Trif-DOPO) and its control samples are incorporated into diglycidyl ether of bisphenol-a (DGEBA) and 4, 4 0 -diamino-diphenyl sulfone (DDS) to prepare flame retardant thermosets, respectively. According to the results of limited oxygen index (LOI), UL94 vertical burning test and cone calorimeter test, the Trif-DOPO/DGEBA/DDS thermoset with 1.2 wt % phosphorus possesses the LOI value of 36% and UL94 V-0 flammability rating, and Trif-DOPO can decrease the peak of heat release rate (pk-hrr) and reduce the total heat release (THR) of thermosets. All these prove better flame retardant performance of Trif-DOPO than that of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide(DOPO). The residue photos of thermosets after cone calorimetry test disclose that Trif-DOPO can promote the formation of thick and tough melting char layer for combined action of the flame retardant groups of Trif-DOPO. The results from thermo gravimetric analysis (TGA) and pyrolysis-gas chromatography-mass spectrometry(py-gc/ms) show that the groups in Trif- DOPO can be decomposed and produce PO 2 fragments, phosphaphenanthrene and phenoxy fragments, which can jointly quench the free radical chain reaction during combustion. Therefore, the excellent flame retardancy of Trif-DOPO is attributed to its flame retardant group-synergic-effect. VC 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, KEYWORDS: flame retardance; thermosets; degradation Received 24 March 2013; accepted 27 June 2013 DOI: /app INTRODUCTION Epoxy resins are widely used as adhesive and electrical encapsulation material due to their remarkable adhesion to many substrates, excellent mechanical performance, chemical and electrical resistances, and low shrinkage on cure. 1,2 But most of the ordinary epoxy resins are easy to burn and hard to extinguish. When they are used in electronic or electrical equipment, some flame retardants are incorporated into epoxy resins to prevent fire. Besides the traditional brominated epoxy resin, 3 the researchers have investigated several kinds of non-halogen flame retardant epoxy resins, such as 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) epoxy resin and phosphazine epoxy resin. A few researches have been done on DOPO epoxy resin from the late 1990s. 4,5 Most of them can effectively enhance the limited oxygen index (LOI) and decrease the heat release rate (HRR), and their flammability rating can reach UL94V-0 when the phosphorus content of the thermosets with DOPO is above 1.5%. 6 8 The phosphazene compounds, especially the cyclotriphosphazene compounds with different substituent groups, 9 11 have been recently reported to increase the LOI value of epoxy thermosets to above 30%, enable the epoxy resins to reach UL94V-0 or UL94V-1 flammability rating with different curing agents, 9 and especially contribute to the high yield of residual char of matrix Even so, considerable attention has been paid to the development of more efficient flame retardant in epoxy resins. An effective way used is to compound the additives containing different flame retardant functional groups or design novel molecular structure with different flame retardant functional groups, which include phosphaphenanthrene, phosphazene, 15 triazine, 16,17 phosphate, 18,19 organic silicon 20,21 etc. Some of the flame retardants containing different structures with higher flame retardancy have been reported for their flame retardant groups synergistic effects. 22,23 But the effects are still necessary to be further explored their essences, which are not disclosed sufficiently currently. VC 2013 Wiley Periodicals, Inc (1 of 8) J. APPL. POLYM. SCI. 2014, DOI: /APP.39709

54 Polymer Degradation and Stability 107 (2014) 98e105 Contents lists available at ScienceDirect Polymer Degradation and Stability journal homepage: Pyrolysis route of a novel flame retardant constructed by phosphaphenanthrene and triazine-trione groups and its flame-retardant effect on epoxy resin Lijun Qian *, Yong Qiu, Nan Sun, Menglan Xu, Guozhi Xu, Fei Xin, Yajun Chen Department of Materials Science & Engineering, Beijing Technology and Business University, Beijing , PR China article info abstract Article history: Received 3 September 2013 Received in revised form 23 April 2014 Accepted 8 May 2014 Available online 24 May 2014 Keywords: Flame retardant DOPO Triazine-trione Synergistic effect Epoxy resin A novel flame retardant TGIC-DOPO, which was constructed by phosphaphenanthrene and triazinetrione groups, was synthesized via a controllable ring-opening addition reaction between 1,3,5- triglycidyl isocyanurate (TGIC) and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO). The flame-retardant effect of TGIC-DOPO on an epoxy resin, diglycidyl ether of bisphenol-a (DGEBA), cured with 4,4 0 -diamino-diphenyl sulfone was investigated. The results of the limited oxygen index (LOI), UL94 vertical burning test, and cone calorimeter test indicated that the TGIC-DOPO imparted flameretardant properties to DGEBA thermosets. When the mass fraction of TGIC-DOPO reached 12wt.%, the DGEBA thermoset acquired a LOI value of 33.3%, UL94 V-0 rating, and the lower peak of heat release rate (pk-hrr) at 481 kw/m 2. Specifically, the DGEBA thermoset with 6wt.% TGIC-DOPO had an LOI value of 33.3%, whereas the DGEBA thermoset with 10wt.% TGIC-DOPO had the highest LOI value of 35.2% among the specimens. Meanwhile, the time to ignition, pk-hrr, average of effective heat of combustion (av-ehc), and total heat release of the DGEBA thermoset were all negatively correlated with the mass fraction of TGIC-DOPO. Moreover, the average CO 2 and CO yields exhibited a downtrend with increasing mass fraction of TGIC-DOPO from 6wt.%. The reduction of av-ehc with increase of TGIC-DOPO content in thermosets confirmed the free radical quenching effect of TGIC-DOPO in gaseous phase during combustion. The macromorphology, micromorphology and element content of the residues from the cone calorimeter test revealed the bi-phase flame-retardant effect of TGIC-DOPO. Furthermore, the pyrolysis route of TGIC-DOPO were investigated via Py-GC/MS, which disclosed that the decomposed TGIC-DOPO with double flame-retardant groups released various fragments with quenching effect on free radical chain reaction of combustion. The fragments enhanced the flame-retardant performance of DGEBA thermosets both in gaseous and condensed phases. The flame-retardant performance of TGIC-DOPO was resulted by the quenching effect of TGIC-DOPO and the synergistic effect of phosphaphenanthrene and triazine-trione groups Elsevier Ltd. All rights reserved. 1. Introduction In the past several decades, epoxy resin has been rapidly and significantly developed in theory and in practical application [1e5]. In the electronic and electrical industry, various epoxy resins are used as adhesives [6,7] and electrical encapsulation materials [8,9] because of their excellent electrical insulation and adhesive properties as well as corrosion resistance. However, most epoxy resins * Corresponding author. Zonghe Building No. 403, Fucheng Road No. 33, Haidian District, Beijing, China. Tel./fax: þ addresses: qianlj@th.btbu.edu.cn, augusqian@163.com (L. Qian). are flammable, which pose potential risks. Thus, to impart flameretardant properties to epoxy resin is necessary for its practical demands [10,11]. The synthesis of novel phosphorus-containing flame-retardant additives and the preparation of phosphorus-containing flameretardant epoxy resins have already been conducted [12e15]. To obtain a highly efficient flame-retardant epoxy resin, several flameretardant chemical structures composed of single or multiple flame-retardant functional groups have been utilized, such as phosphaphenanthrene [16e18], cyclotriphosphazene [19,20], phosphorus-containing silsesquioxane [21], pentaerythritol diphosphonate [22,23], triazine [24,25], and triazine-trione [26e28] structures. Moreover, several novel flame retardant / 2014 Elsevier Ltd. All rights reserved.

55 Polymer 55 (2014) 95e101 Contents lists available at ScienceDirect Polymer journal homepage: Bi-phase flame-retardant effect of hexa-phenoxy-cyclotriphosphazene on rigid polyurethane foams containing expandable graphite Lijun Qian *, Fafei Feng, Shuo Tang Department of Materials Science & Engineering, Beijing Technology and Business University, No. 11, Fucheng Road, Haidian District, Beijing , PR China article info abstract Article history: Received 30 August 2013 Received in revised form 2 December 2013 Accepted 6 December 2013 Available online 15 December 2013 Keywords: Polyurethane foam Flame retardant Hexa-phenoxy-cyclotriphosphazene The flame-retardant rigid polyurethane (PU) foams with hexa-phenoxy-cyclotriphosphazene/expandable graphite (HPCP/EG) were prepared through box-foaming in our laboratory. The flame retardancy of PU foams was characterized using the limiting oxygen index and cone calorimeter. The results show that the incorporation of HPCP into the PU foams containing EG enhanced flame retardancy. The main degradation process of HPCP in PU foams was investigated by pyrolysis gas chromatography/mass spectroscopy. HPCP during combustion generated phenoxyl and PO 2 free radicals, which could quench the flammable free radicals produced by the matrix and hamper the free radical chain reaction of combustion. This observation shows that HPCP produced a gas-phase flame-retardant effect in this specimen. Additionally, micro-morphology, elemental composition and content of residual char of the flameretardant PU foams after the cone calorimeter test were also characterized using scanning electron microscope and energy dispersive X-ray microanalyser. The results exhibit that the partial phosphorus from HPCP remained in the residual char, and HPCP significantly enhanced the strength and compatibility of the char layer formed by the PU foams containing EG. These results indicate the important function of HPCP in condensed phase. Thus, HPCP exhibited gas-phase and condensed-phase flameretardant effects on the PU/EG foams. Ó 2013 Elsevier Ltd. All rights reserved. 1. Introduction Rigid polyurethane (PU) foams have been extensively used in various fields, such as construction, oil pipeline, refrigeration, aeronautics, and astronautics, because rigid PU foams have several excellent properties, which include light weight, high compressive strength, low thermal conductivity, good cohesiveness, and low water absorption [1e7]. However, neat PU foams are considerably flammable because they consist of a large number of aliphatic segments and possess a porous cellular structure, which increases the surface contact area between materials and air [8e10]. Upon ignition, PU foams rapidly burn, release a large amount of heat, and then reach the peak of the burning intensity in a short time [11]. The peaks of heat release rate (PHRR) of neat PU foams are almost above 300 kw/m 2 according to our laboratory experiments and the related reports. The flammability of neat PU foams is a disadvantage that restricts their application in various fields. Therefore, * Corresponding author. Tel.: þ , þ (mobile); fax: þ address: qianbtbu@163.com (L. Qian). decreasing the burning rate and PHRR of PU foams contributes to the enhancement of flame retardancy of PU foams. In recent years, amounts of experimental investigations on flame retardancy of PU foams have been reported. The selection of appropriate flame retardants for PU foams is important to preserve the other excellent properties of the foams. Some researchers have adopted addition-type flame retardants, such as expandable graphite (EG) [12e15], ammonium polyphosphate (APP) [16], melamine cyanurate [17], triethyl phosphate [18], triphenyl phosphate [19], tricresyl phosphate [20], dimethyl methylphosphonate (DMMP) [21], and alkylphosphinates [22], to endow PU foams with fire retardancy. Other researchers have used reactive flame retardants, which usually contain phosphorus, nitrogen and hydroxyl, to achieve the same aim [23e25]. Moreover, EG is an effective flame retardant in PU foams and has an important function in condensed phase through the formation of an intumescent carbonaceous layer at high temperature. Further, the methods of combining EG with other flame retardants have attracted increasing attention, such as EG and hollow glass microsphere [26], EG and whisker silicon oxide [27], EG and APP [28,29], and EG and DMMP [30,31]. The composition of flame retardants can effectively enhance the flameretardant property of PU foams /$ e see front matter Ó 2013 Elsevier Ltd. All rights reserved.

56 Author's Personal Copy Polymer 68 (2015) 262e269 Contents lists available at ScienceDirect Polymer journal homepage: High-performance flame retardancy by char-cage hindering and free radical quenching effects in epoxy thermosets Lijun Qian *, Yong Qiu, Jingyu Wang, Wang Xi Department of Materials Science & Engineering, Beijing Technology and Business University, Beijing , PR China article info abstract Article history: Received 3 January 2015 Received in revised form 28 April 2015 Accepted 17 May 2015 Available online 22 May 2015 Keywords: Flame retardant DOPO Epoxy resin A flame retardant, tri-(3-dopo-2-hydroxypropan-1-yl)-1, 3, 5-triazine-2, 4, 6-trione (TGIC-DOPO) containing both phosphaphenanthrene and triazine-trione groups, is introduced into diglycidyl ether of bisphenol-a (EP) thermosets respectively cured by 4,4 0 -diamino-diphenyl methane (DDM), 4,4 0 -diaminodiphenyl sulfone (DDS), and m-phenylenediamine (m-pda). TGIC-DOPO exhibits excellent flameretardant effects in EP/DDM compared with EP/DDS and EP/m-PDA. The thermoset cured with DDM with only 4%TGIC-DOPO reaches UL94 V-0 rating and possesses a limited oxygen index (LOI) value of 35.6%. The macroscopic and microscopic morphologies of the residues reveal that a cage-like char crown envelops the fire, thus hindering oxygen from permeating inside and inhibiting the release of PO and phenol free radicals with quenching effect. The char-cage hindering effect is the main reason for the high LOI values. TGIC-DOPO in EP/DDM not only locks more carbon components in condensed phase but also facilitates to release more pyrolyzed PO and phenol free radicals. The concentrated release of PO and phenol free radicals exert a strong quenching effect, which is the main mechanism for the high flameretardant rating with the addition of relatively low amount of TGIC-DOPO. Therefore, the integration of char-cage hindering and free radical quenching effects enables excellent flame retardancy to epoxy thermosets Elsevier Ltd. All rights reserved. 1. Introduction In the past two decades, flame-retardant epoxy resins have become important advanced materials in electronic and electrical equipment industries because of their excellent adhering, physicalmechanical, electric, and flame-retardant properties [1e6]. Therefore, they are widely applied as binders in printed circuit boards [7e9] and as packaging materials in light-emitting diode illuminators [10e12]. To enhance flame-retardant efficiency and comprehensive properties of epoxy resins, a series of novel flame retardants were prepared and incorporated into epoxy resins [13e17]. Most of the studies have focused on the low loading and high flame-retardant efficiency of additives [18,19]. Usually, novel flame-retardant systems may be developed through three ways. The simplest one is to compound some known additives [20e26], in which the mixtures rely on the component synergistic effect to * Corresponding author. Department of Materials Science & Engineering, Beijing Technology and Business University, No.11, Fucheng Road, Haidian District, Beijing , PR China. Tel./fax: þ , þ (mobile). address: qianbtbu@163.com (L. Qian). enhance flame-retardant efficiency; another way is to synthesize novel flame retardants constructed by several flame-retardant functional groups [27e30] and the novel compounds will possess the higher flame-retardant efficiency by means of the group synergistic effect; the last method is to create some flame-retardant molecules with a novel structure [31e35], in which high flameretardant properties and new mechanism will be achieved. In recent years, some additives which were constructed by combining different flame-retardant functional groups have been reported. These additives are composed of phosphazene/phosphaphenanthrene [36,37], phosphaphenanthrene/triazene [38,39], phosphaphenanthrene/poss [40], or other functional groups [41,42]. All of these additives possess excellent flame-retardant efficiencies, which confirms that the methods used in these studies can be employed to obtain high-efficiency flame retardants. Although the former researchers have made great effort on developing novel flame retardant and various high efficiency flame retardant have also been discovered and applied, the further research to develop much higher efficiency and marketacceptability flame retardant molecules is still essential because it would promote the sustainable development of industries greatly / 2015 Elsevier Ltd. All rights reserved.

57 Integrated Ferroelectrics An International Journal ISSN: (Print) (Online) Journal homepage: Flammability and anti-dripping behaviors of polylactide composite containing hyperbranched triazine compound Yajun Chen, Xiaojun Mao, Lijun Qian & Chunzhuang Yang To cite this article: Yajun Chen, Xiaojun Mao, Lijun Qian & Chunzhuang Yang (2016) Flammability and anti-dripping behaviors of polylactide composite containing hyperbranched triazine compound, Integrated Ferroelectrics, 172:1, 10-24, DOI: / To link to this article: Published online: 01 Jun Submit your article to this journal Article views: 51 View Crossmark data Full Terms & Conditions of access and use can be found at Download by: [Beijing Technology and Business University] Date: 18 November 2016, At: 21:17

58 Preparation and characterization of surface-modified ammonium polyphosphate and its effect on the flame retardancy of rigid polyurethane foam Yajun Chen, 1,2 Linshan Li, 1,2 Wei Wang, 1,2 Lijun Qian 1,2 1 School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, No. 11, Fucheng Road, Haidian District, Beijing , People s Republic of China 2 Beijing Key Laboratory of Quality Evaluation Technology for Hygiene and Safety of Plastics, Beijing , People s Republic of China Correspondence to: Y. Chen (E- mail: chenyajun@th.btbu.edu.cn) and L. Qian (E- mail: qianlj@th.btbu.edu.cn) ABSTRACT: A functional surface-modification agent was synthesized via a reaction between hexachlorocyclotriphosphazene and g-aminopropyl triethoxysilane. Ammonium polyphosphate (APP) was modified with this agent and then incorporated into a rigid polyurethane foam (RPUF). Fourier transform infrared spectroscopy, 1 H-NMR, and X-ray photoelectron spectroscopy were used to characterize the modified ammonium polyphosphate (M-APP). The results show that the dispersibility was improved and the particle size decreased after the modification. The limiting oxygen index and cone calorimetry test results show that M-APP enhanced the flameretardant properties of RPUF. The peak heat-release rate of polyurethane (PU)/20% M-APP decreased by 51.18% compared with that of PU APP. The scanning electron microscopy results illustrate that M-APP facilitated the formation of intumescent and compact char. The excellent flame-retardant performance of M-APP resulted from the flame-inhibition and barrier effects, which were attributed to the phosphazene group and the intumescent char, respectively. VC 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, KEYWORDS: flame retardance; foams; polyurethanes Received 10 February 2017; accepted 26 May 2017 DOI: /app INTRODUCTION Polyurethane (PU) foams, which are prepared by the reaction between polyols and isocyanates, 1 are used extensively in insulation, packaging, construction panels, furniture, and automobiles because of their superior mechanical properties, excellent cushioning, and good durability. 2 4 PU is flammable in air and produces toxic smoke; this is associated with its chemical structure. 5 The disadvantage of flammability impedes the wide application of PU. 6 Therefore, it is essential that the fire performance of PU be improved by flame retardants. 7 The commonly used flame retardants in PU foams can be divided into reaction-type and addition-type flame retardants. 8 As an addition-type flame retardant, ammonium polyphosphate (APP) has wide applications in many polymer-based materials because it is halogen free and has a low toxicity and a low cost. 9,10 However, it has few applications in PU, particularly in spraying PU. The poor compatibility of APP with the PU matrix results in a low flame-retardant efficiency. 11 Moreover, the large particle size of APP can lead to the easy blocking of the spray nozzle, and this influences the spraying process. At present, the surface-modification techniques of APP are as follows: (1) the microencapsulation technique, (2) modification by a coupling agent, 15,16 (3) modification by a surface active agent, 17 and (4) modification by melamine. 18 The surfacemodification method (method 1) is aimed at overcoming the poor water resistance of APP. The purpose of methods 2 and 3 is to improve the compatibility of APP with the polymer matrix. Method 4 is designed to enhance the flame-retardant efficiency of APP. So far, there have been few reports on the surfacemodification technique, which can improve the dispersibility and flame-retardant efficiency of APP at the same time. Cyclotriphosphazene, consisting of nitrogen and phosphorus atoms, exhibits thermal stability and flame-retardant properties because of its phosphazene structure. 19,20 The extreme reactivity of the six reactive chlorine atoms in hexachlorocyclotriphosphazene (HCCP) can be used to introduce a number of functional groups for preparing products with special properties. 21 Silane coupling agents have been used as the surface-modification agent for modifying APP. 22 The dispersibility of APP is improved by the surface modification of the silane coupling agents. Moreover, silane coupling agents, such as g-aminopropyl triethoxysilane (KH-550), can engage in a nucleophilic substitution reaction with HCCP. On the basis of these reasons, HCCP and KH-550 were chosen to synthesize a flame-retardant, functional surface-modification VC 2017 Wiley Periodicals, Inc (1 of 9) J. APPL. POLYM. SCI. 2017, DOI: /APP.45369

59 Synthesis of a novel flame retardant containing phosphazene and triazine groups and its enhanced charring effect in poly(lactic acid) resin Yajun Chen, Wei Wang, Zhiqi Liu, Yuanyuan Yao, Lijun Qian Department of Materials Science & Engineering, Beijing Technology and Business University, Beijing , People s Republic of China Correspondence to: Y. Chen ( chenyajun@th.btbu.edu.cn) and L. Qian ( qianlj@th.btbu.edu.cn) ABSTRACT: A novel flame retardant heax-[n,n 0,N 00 -tris-(2-amino-ethyl)-[1,3,5] triazine-2,4,6-triamine] cyclotriphosphazene (HTTCP) containing phosphazene and triazine groups was synthesized and characterized by Fourier transform infrared spectroscopy (FTIR), solid-state 1 H and 13 C nuclear magnetic resonance (NMR) spectroscopy. HTTCP was applied to PLA matrix. The results of thermal gravimetric analysis (TGA), the limited oxygen index (LOI), and cone calorimeter test indicated that the HTTCP enhanced the thermal stability and flame retardant properties of PLA. When the mass fraction of HTTCP was 25 wt %, the PLA composite acquired a LOI value of 25.2% and the lower pk-hrr at 290 kw/m 2. The excellent flame retardancy of HTTCP was attributed to the group synergistic effect between phosphazene and triazine groups. However, when combined HTTCP with APP (the total amount remaining 25 wt %, the ratio of HTTP to APP are 1:1 and 1:2), high values of LOI (over 40%) and UL94 V-0 rating without dripping reached simultaneously. Meanwhile, the heat release rate, total heat release and mass loss rate were all decreased dramatically. Scanning electron microscopy (SEM) demonstrated that HTTCP/APP system benefited to the formation of more intumescent, dense, compact char layer on the materials surface which could effectively prevent the underlying material from degradation during burning. VC 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, KEYWORDS: flame retardance; thermal properties; thermogravimetric analysis (TGA); thermoplastics Received 2 August 2016; accepted 11 November 2016 DOI: /app INTRODUCTION Polylactide (PLA) is one of the most outstanding and available biodegradable polymers. It has achieved the extensive applications for packaging, textiles, biomedical materials, engineering, and other fields. 1 4 However, having high combustibility and melt dripping distinctly restricts its applications especially in electronic and electrical fields. Therefore, the PLA with superior flame resistance have necessarily been required to avoid the fire risks. A number of approaches have been attempted to enhance the flame resistance of PLA. For example, Reti et al. 5 evaluated the efficiency of intumescent formulations using ammonium polyphosphate (APP), pentaerythritol (PER), lignin, and starch to flame retardant PLA; results showed that the flame retardancy of PLA had been improved significantly as the flame retardant reached 40 wt % loading. Zhan et al. 6,7 investigated the flame retardancy and antidripping properties of PLA composites with intumescent flame-retardant (IFR) and different synergists. Tao et al. 8,9 synthesized cyclomatrix network polymer and hyperbranched polyamine as charring agent for PLA to obtain good flame retardancy. Additionally, Wang et al. 10,11 designed various phosphorus-containing PLA composites with good performance during combustion. According to these studies, it can be concluded that adding the flame retardant containing phosphorus and nitrogen is considered as an effective route. It is well known that the phosphoruscontaining moieties form condensed char layer; the nitrogencontaining ones can release inert nitrogen, ammonia and nitrogen oxide gases to dilute oxygen and facilitate the expansion of the layers during the combustion of PLA composites. 4 Phosphazenes and their derivatives are a unique class of hybrid inorganic-organic compounds contained alternating phosphorus and nitrogen in their skeleton and organic groups in their branched chain. Such a unique chemical structure offers the synergism of the phosphorus-nitrogen combination resulting in outstanding flame retardancy. 12 Meanwhile, it is found that triazines and their derivatives are good charring agents. These agents have superior charring effect because they contain abundant nitrogen and possess a structure of tertiary nitrogen. 13 VC 2016 Wiley Periodicals, Inc (1 of 8) J. APPL. POLYM. SCI. 2017, DOI: /APP.44660

60 Review Article Intumescent flame-retardant poly(1, 4-butylene terephthalate) with ammonium polyphosphate and a hyperbranched triazine charring-foaming agent: Flame retardancy performance and mechanisms Journal of Fire Sciences 1 24 Ó The Author(s) 2017 Reprints and permissions: sagepub.co.uk/journalspermissions.nav DOI: / journals.sagepub.com/home/jfs Bo Xu, Xiao Wu, Lijun Qian, Yong Qiu, Shuo Tang, Wang Xi and Youyou Fang Date received: 1 January 2017; accepted: 16 April 2017 Abstract Intumescent flame-retardant poly(1, 4-butylene terephthalate) composites with ammonium polyphosphate and a hyperbranched triazine charring-foaming agent were prepared through melt blending. The flame retardancy, pyrolysis behavior, and flame-retardant mechanism of flameretardant poly(1, 4-butylene terephthalate) were investigated using flammability tests, cone calorimeter measurements, thermogravimetric analysis including evolved gas analysis, and residue analysis (Fourier transform infrared and scanning electron microscopy). The results showed that the intumescent flame retardant with the appropriate ammonium polyphosphate/hyperbranched triazine charring-foaming agent mass ratio (4/1) could significantly improve the flame retardancy of poly(1, 4-butylene terephthalate), and the highest Limiting Oxygen Index value and UL-94 V-0 rating was reached. The peak heat release rate and total heat evolved remarkably decreased, School of Materials Science and Engineering, Beijing Technology and Business University, Beijing, P.R. China Corresponding authors: Bo Xu, School of Materials Science and Engineering, Beijing Technology and Business University, Beijing , P.R. China. xubo@btbu.edu.cn Lijun Qian, School of Materials Science and Engineering, Beijing Technology and Business University, Beijing , P.R. China. qianlj@th.btbu.edu.cn

61 Polymer Degradation and Stability 140 (2017) 166e175 Contents lists available at ScienceDirect Polymer Degradation and Stability journal homepage: Terminal group effects of phosphazene-triazine bi-group flame retardant additives in flame retardant polylactic acid composites Yajun Chen a, b, *, Wei Wang a, b, Yong Qiu c, Linshan Li a, b, Lijun Qian a, b, **, Fei Xin a, b a School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, Beijing , PR China b Beijing Key Laboratory of Quality Evaluation Technology for Hygiene and Safety of Plastics, Beijing , PR China c School of Materials, Beijing Institute of Technology, Beijing , PR China article info abstract Article history: Received 3 February 2017 Received in revised form 14 April 2017 Accepted 30 April 2017 Available online 2 May 2017 Keywords: Flame retardant Polylactic acid Synergistic effect Phosphazene Triazine Three phosphazene-triazine bi-group flame retardant additives (A1, A2, A3) with different terminal groups were synthesized from hexachlorocyclotriphosphazene (HCCP), cyanuric chloride and amine compounds (ethylenediamine, aniline, or p-phenylenediamine). Then they were applied with ammonium polyphosphate (APP) to prepare flame-retardant polylactic acid (PLA), separately. The molecule structures and thermal stabilities of these three flame retardant additives were characterized by Fourier transformed infrared spectrometry (FTIR), 1 H and 13 C Solid-State NMR spectrometer and thermogravimetric analysis (TGA). The flame-retardant properties and mechanism of the flame-retardant PLA composites were investigated by the limited oxygen index (LOI) test, vertical burning test, cone calorimeter test (CCT), scanning electron microscopy (SEM), and thermogravi-metric analyzer coupled to a Fourier-transform infrared spectrometer (TGA-FTIR). Results showed that the combination of phosphazene-triazine bi-group flame retardant additive with amino-terminated groups (A1 or A3) and APP brought better flame retardant properties to PLA resin than that of A2 without amino-terminated groups. PLA/A1/APP system got the best flame retardant properties, which exhibited the highest LOI value of 34.3% and preferably achieved UL-94 V-0 rating without dripping. Meanwhile, it not only obtained the lowest pk-hrr, THR, and TSR, but also reserved the largest amount of residual char, compared with other flame-retardant PLA composites. Such a significant improvement in flame retardancy was attributed to the PO 2 $ radical quenching effect and inert gas dilution effect in gas phase, as well as barrier and protective effect and charring effect in condense phase. Besides, the poor performance on flame retardancy of PLA/A2/APP system was due to the lack of barrier and protective effect and charring effect in condense phase. All these revealed that the adjustment on terminal groups of flame-retardant additives not only affects their flame-retardant work mode, but also helps to explore the more efficient flame-retardant structures or systems Elsevier Ltd. All rights reserved. 1. Introduction Over the past decade, with the urgent environmental pollution and shortage of petroleum energy source, biodegradable polymeric material has attracted more and more attention. Polylactic acid * Corresponding author. School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, No.11, Fucheng Road, Haidian District, Beijing , PR China. ** Corresponding author. School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, No.11, Fucheng Road, Haidian District, Beijing , PR China. addresses: chenyajun@th.btbu.edu.cn (Y. Chen), qianlj@th.btbu.edu.cn (L. Qian). (PLA) is one of the best-known biodegradable aliphatic polyesters that can be produced by renewable sources (mainly starch and sugar). PLA has been used in various applications due to its excellent mechanical properties. Nowadays the high molecular weight PLA has broadened its applications in electronic and electrical devices, mechanical and automotive parts industries [1e5]. Unfortunately, PLA has very poor flame retardancy especially the serious dripping during burning, which severely restricts its potential application. Therefore, the flame retardant modification of PLA has been an urgent task. In recent years, intumescent flame retardant (IFR) additives have received extensive attention on the flame retardation application of PLA due to their advantages of low smoke and low toxicity / 2017 Elsevier Ltd. All rights reserved.

62 RSC Advances Open Access Article. Published on 09 October Downloaded on 01/12/ :21:43. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. PAPER Cite this: RSC Adv., 2017,7, Received 10th August 2017 Accepted 2nd October 2017 DOI: /c7ra08857d rsc.li/rsc-advances 1. Introduction A novel triazine-rich polymer wrapped MMT: synthesis, characterization and its application in flame-retardant poly(butylene terephthalate) Fei Xin, * a Chao Guo, a Yu Chen, b Hailong Zhang a and Lijun Qian A novel flame retardant (PTAC MMT) was prepared by wrapping montmorillonite (MMT) with poly(2,4,6- triallyloxy-1,3,5-triazine) (TAC) via in situ polymerization, and its structure and properties were characterized by Fourier transformed infrared (FT-IR) spectroscopy, 1 H nuclear magnetic resonance ( 1 H NMR) and 13 C NMR, transmission electron microscopy (TEM), X-ray powder diffraction (XRD) and thermogravimetric analysis (TGA) measurements. The PTAC MMT and aluminum diethylphosphinate (AlPi) were then incorporated into poly(butylene terephthalate) (PBT) to improve the flame retardancy. The sample containing 1.67 wt% PTAC MMT and 8.33 wt% AlPi had a LOI value of 36.4% and achieved UL94 V-0 classification. The wrapping flame retardants exhibited excellent anti-dripping effect in PBT composite. This work could provide a novel way to prepare modified MMT and the as-prepared flame retardants. Polybutylene terephthalate (PBT) is an important thermoplastic polymer in modern industry, and has been widely used because of its good mechanical properties, chemical resistance, low cost, high processability, and moderate recyclability. 1 3 However, they are ammable and tend to drip during burning, which contributes to re spread. Therefore, it is a challenging task and has caused great concern to impart both ame retardancy and dripping resistance to PBT. 4 7 Although several commercially available systems for ame retardancy of PBT consist of a halogen-containing additive and a synergist, they are persistent, bio-accumulative, toxic, and are prohibited under various legislations To obtain a highly efficient and safer ame-retardant PBT, the syntheses of some new organophosphorous compounds or phosphorus nitrogen compounds and inorganic additives have already been conducted The improvement of ame retardancy attributed to the formation of network char layer created by decomposition of triazine-rich polymer, which can hinder the heat and mass transport Montmorillonite (MMT) was frequently used in many polymer nanocomposites owing to its particular nano-layer structure However, the agglomeration of MMT particles might cause poor dispersion in polymer matrix, which also deteriorates the ame retardancy efficiency and mechanical performances Therefore, much effort is necessary devoted to improve the dispersibility of the MMT a School of Materials and Mechanical Engineering, Beijing Technology and Business University, Beijing , People's Republic of China. xinfei@th.btbu.edu.cn b Beijing Huateng Hightech Co.,Ltd., Beijing , PR China through organo- or nano-modication of MMT To design an efficient triazine-rich ame-retardant and to study the effect of their wrapped structure on the properties of PBT composites is of great signicance for promoting the development of this eld. For example, higher ame retardancy obtained and the mechanical properties improved, which can be attributed to the good interfacial adhesion between wrapped MMT and the polymer matrix. This work mainly aims at the reduction of the agglomeration of MMT layers in PBT nanocomposites, a triazine-rich polymer, poly(2,4,6-triallyloxy-1,3,5-triazine) (PTAC) wrapped on the surface of MMT was designed and synthesized by in situ intercalation polymerization to obtain PTAC MMT. The PBT composite containing a small amount of PTAC MMT in combination with AlPi was prepared, and its ammability was characterized. The synergistic ame-retardant effects of PTAC MMT/ AlPi were also analyzed. This study will focus on exploring a new route for the efficient use of MMT compared with the common organo-modied MMT. 2. Experimental View Article Online View Journal View Issue 2.1. Raw materials TAC, 2,4,6-triallyloxy-1,3,5-triazine, were supplied by TCI Shanghai Huacheng Industrial Development Corp. Ltd., China. The original montmorillonite (Na-MMT) in this study was provided by Zhejiang Fenghong Clay Corp. Ltd., China. Aluminum diethylphosphinate (AlPi) was obtained from Clariant Chemicals (China) Ltd. Poly(- butylene terephthalate) (PBT) was purchased from Nantong Xingchen synthetic material CO. Ltd., China. Unless otherwise indicated, all materials were used as-received. a RSC Adv., 2017, 7, This journal is The Royal Society of Chemistry 2017

63 Phosphorus-containing silica gel-coated ammonium polyphosphate: Preparation, characterization, and its effect on the flame retardancy of rigid polyurethane foam Yajun Chen, 1,2 Linshan Li, 1,2 Lifeng Xu, 1,2 Lijun Qian 1,2 1 School of Materials Science and Mechanical Engineering, Beijing Technology and Business University, Beijing , People s Republic of China 2 Beijing Key Laboratory of Quality Evaluation Technology for Hygiene and Safety of Plastics, Beijing , People s Republic of China Correspondence to: Y. Chen (E- mail: chenyajun@th.btbu.edu.cn) and L. Qian (E- mail: qianlj@th.btbu.edu.cn) ABSTRACT: A phosphorus-containing silica gel was synthesized via a reaction between phenyl dichlorophosphate, poly(ether polyol), and g-aminopropyltriethoxysilane. Ammonium polyphosphate (APP) was modified by the synthesized phosphorus-containing silica gel (MAPP) and then incorporated into the rigid polyurethane foam (PU). Results showed that APP had a smaller particle size, lower initial decomposition temperature, better heat resistance at high temperature, and better compatibility with PU matrix after the modification. The cone calorimeter test results showed that the incorporation of MAPP obviously reduced the values including peak of heat release rate, total heat release, average effective heat of combustion, and total smoke release, and increased the char yield of PU composite comparing with APP. The improved flame retardancy of PU/MAPP composite was attributed to the quenching effect of PO and PO 2 free radicals released by MAPP in the early stage and the improved thermal stability of phosphorus- and siliconcontaining char layer formed in the later stage. VC 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, KEYWORDS: flame retardance; foams; polyurethane Received 25 October 2017; accepted 3 February 2018 DOI: /app INTRODUCTION Polyurethane foams have been widely used in a variety of industrial fields such as automobile industry, refrigeration, construction, and petroleum plant, due to its excellent physical and mechanical properties, light weight, and low thermal conductivity. 1 3 However, polyurethane foam is a highly flammable material, and this drawback restricts the applications. 4 Moreover, polyurethane foam can generate a large amount of heat and some toxic smoke, such as CO and HCN during the combustion, that can be harmful to people s health. 5 Therefore, it is essential to enhance the flame retardancy of polyurethane foam. The flame retardants, such as halogen flame retardants and phosphorus flame retardants, have been used to improve the flame retardancy of polyurethane foam. Ammonium polyphosphate (APP) and the modified APP as additional flame retardants have been applied in many polymer-based materials because of its favorable features such as halogen-free, low toxicity, and low smoke production. 6 8 It showed that APP played a better flame-retardant performance in polyurethane foam in other previous research However, in our previous work, we found that the flame-retardant property is not better when APP added in polyurethane foam alone. 12 We thought the result is caused by the following reasons. First, the initial degradation temperature of APP is about 300 8C, and the evolution products at this stage are mainly NH 3 and H 2 O, which can play the gas dilution effect. However, the polyurethane foam has decomposed over 50% at this temperature, because the initial degradation temperature of polyurethane foam is about C. 13,14 Therefore, APP cannot inhibit the combustion of PU timely. Second, the flameretardant system is lack of carbon source. APP is used as an acid source and a blowing agent in intumescent flame retardant system. 15 The lack of carbon source is not conducive to promote char-forming for matrix during combustion. In this work, phenyl dichlorophosphate (PDCP), low molecular poly(ether polyol) (DP400), and g-aminopropyltriethoxysilane (KH-550) were chosen to synthesize the phosphorus-containing silica gel. APP was then coated by the phosphorus-containing silica gel. It is conducive to improve the compatibility between APP and matrix by using silica gel. DP400 contains hydroxyl groups, which can react with the poly(phosphoric acid) VC 2018 Wiley Periodicals, Inc (1 of 11) J. APPL. POLYM. SCI. 2018, DOI: /APP.46334

64 4 团队研究生获授权国家发明专利

65 序号 团队研究生获授权国家发明专利 姓名专利名称专利号日期 钱立军, 郭秀安, 叶龙健 钱立军, 郭秀安, 叶龙健 钱立军, 叶志殷, 冯发飞, 汤朔, 邱勇 钱立军, 冯发飞, 周侃 钱立军, 邱勇, 冯发飞, 汤朔, 孙楠 钱立军, 陈雅君, 邱勇 许博, 钱立军, 许梦兰 钱立军, 邱勇, 奚望 9 钱立军, 孙楠 10 钱立军, 许梦兰 一种无卤阻燃环氧树脂及其制备方法一种磷杂菲磷腈无卤阻燃剂的制备方法一种大粒径三聚氰胺氰脲酸盐的制备方法磷腈化合物阻燃聚碳酸酯组合物 一种磷杂菲衍生物阻燃剂 一种磷氮系无卤阻燃环氧树脂一种无卤膨胀阻燃 PBT 及其制备方法一种磷氮系无卤阻燃聚乳酸材料基于磷杂菲和磷腈基团的双基化合物 制备方法及应用 一种高稳定性成炭剂及其制备方法 ZL ZL ZL ZL ZL ZL ZL X ZL X ZL X ZL

66 11 钱立军, 汤朔 12 钱立军, 王靖宇 辛菲, 陈宇, 王士军, 钱立军, 李明 陈雅君, 钱立军, 王伟 陈雅君, 钱立军, 王伟, 岐晓青 陈雅君, 王伟, 钱立军 一种新型磷氮系无卤阻燃尼龙 6 及其制备方法一种含阻燃剂的可发聚苯乙烯颗粒的制备方法一种纳米阻燃环氧树脂及其制备方法一种基于磷腈和三嗪基团的双基化合物及其制备方法一种含硅阻燃聚醚表面处理剂及其制备方法及应用一种基于原位掺杂纳米级金属化合物的磷腈 / 三嗪双基分子阻燃剂及其制备方法 ZL ZL ZL ZL ZL ZL

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84 5 研究生专利成果转化证明 序号 1 2 姓名专利名称专利号转让情况 钱立军, 王靖宇 钱立军, 邱勇, 冯发飞, 汤朔, 孙楠 一种含阻燃剂的可发聚苯乙烯颗粒的制备方法 一种磷杂菲衍生物阻燃剂 ZL ZL 专利权已转让山东润科化工股份有限公司 专利权已授权星贝达 ( 北京 ) 使用

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