Halloysite. Nanotubes Epoxy. NanoComposites

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1 Halloysite Halloysite Nanotubes Nanotubes Epoxy Epoxy NanoComposites NanoComposites Songshan Zeng Christopher Reyes Songshan Zeng Christopher Reyes

2 Epoxy Chemistry Epoxy systems consist of a liquid epoxy resin manufactured from epichlorohydrin and Bisphenol-F with a cycloaliphatic amine curing agent. The curing agent facilitates the opening of the epoxide groups in the epoxy resin which leads to a chain reaction and cross linking. Epoxies are used in many applications in various industries because of their superior mechanical, adhesive, electrical and chemical resistance properties EPON Resin 862 and EPIKURE Curing Agent will be used for all composites.

3 Chemical models structure and molecule makeup of EPON62 and EPI W Cure Chemical model structure and molecule of EPI W Cure 1 Chemical model structure and molecule of EPON EPON 862 and Curing Agent Cross-Linked in a Square Configuration 2

4 NanoComposites Introduction Nanocomposite are composed of two or more materials which have different physical or chemical properties, with at least one being in the nanometer scale. Nanofillers such as halloysite nanotubes, carbon nanotubes, and nano materials are desirable because they have superior physical and chemical properties Nano materials are incorporated into the epoxy to exploit their properties. All composites in this research will be epoxy based with halloysite nanofillers of various weight proportions.

5 Halloysite Introduction Halloysite [Al 2 (OH) 4 Si 2 O 5 2H 2 O] is an inorganic hollow nanotube. The internal diameter and length of HNTs vary from 15 to 100 nm and from 0.02 to 2 30 m, respectively. The mismatch in the periodicity between the oxygen sharing tetrahedral SiO 4 sheets and adjacent octahedral A1O 6 sheets leads to the forming tubular HNTs covered with surface hydroxyl groups. 7 Crystalline Structure of Halloysite Cite from Yuan, P.; Southon, P. D.; Liu, Z.; Green, M. E. R.; Hook, J. M.; Antill, S. J.; Kepert, C. J. J. Phys. Chem. C 2008, 112 (40),

6 Halloysite Nanotube Structure Structure of halloysite monolayer and cross section views of (a) a (12,0) imogolite nanotube and (b) a (12,0) halloysite nanotube. White atoms are H, red O, gray Al, and yellow Si. Luciana Guimara es,, Andrey N. Enyashin,, Gotthard Seifert, and He lio A. Duarte*, Structural, Electronic, and Mechanical Properties of Single- Walled Halloysite Nanotube Models January 30, 2010; Department of Chemistry, ICEx, UniVersidade Federal de Minas Gerais, Belo Horizonte, MG,Brazil, Department of Natural Science,

7 SEM images of HNTs TEM images of HNTs Images- Newly emerging applications of halloysite nanotubes: a review, Mingliang Du,a,b Baochun Guob and Demin Jiab Published online in Wiley Interscience: 12 January 2010

8 Recent Work Introduction 1. Preparation of two pure epoxy samples (labeled as #1epoxy and #2 epoxy )from EPON Resin 862 and EPIKURE Curing Agent 2. Purification of Halloysite Nanotubes (HNT) 3. Preparation of epoxy/neat HNT(weigh ratio= 100:1) nanocomposite 4. Mechanical test for pure epoxy and nanocomposite

9 Preparation for #1epoxy sample Resin & Curing agent weighed, ratio (24:100) Each diluted with acetone and mixed rotary evaporation in 60 at 100 rpm When free of solvent (about 30mins) Cured at 80 for 1.5hrs then at 150 for 1.5hrs Pour into a silicon mold

10 Problems & solutions for #1epoxy Problems: Numerous bubble were showed in the samples. Reasons: Entrapped gas during mixing and solvent not completely evaporated Solutions: Use less solvent and degas the sample in vacuum oven

11 Preparation for #2 epoxy Resin & Curing agent weighed, ratio (24:100) Each diluted with acetone and mixed rotary evaporation in 60 at 100 rpm Cured in 80 for 1.5hrs and then in 150 for 1.5hrs poured into a silicon mold Degassed under vacuum oven at 60 for 2.5 hrs New Step*

12 Concerns for #2 epoxy 1. The 60 for degassing process is close to the 80 for curing with could cause premature cross-linking. 2. The degassing time should be modified to a shorter time and a lower temperature.

13 Preparation for epoxy/n-hnt (100:1) Purify HNT and weigh sample HNT sonicated 15mins in acetone polymers diluted in acetone and mixed with HNT the mixture sonicated 1 hr Cured in 80 for 1.5hrs and then in 150 for 1.5hrs poured into a silicon mold Degassed at vacuum oven at 60 for 1.5 hrs rotary evaporation in 60 at 100 rpm for 30 mins

14 Concerns for epoxy/n-hnt (100:1) The color of mixture is green before curing; pure epoxy is amber. Possible reasons, Fe impurities in the HNTs Will need to remove Fe impurities

15 Mechanical Testing of Neat Epoxy Sensor: 1000 lbs Sensor: 1000 Test speed: 5mm/ lbs ; Test speed: min 5 mm/min Standard: ASTM D ASTM D *Max should be in the 2000N range

16 Mechanical Testing of NanoComposite Sensor: 1000 lbs Sensor: 1000 Test speed: 5mm/ lbs ; Test speed: min 5 mm/min Standard: ASTM D ASTM D *Max higher than neat as expected but, should also be in the 2000N range

17 Future Work- HNT modification HNT surface modification with Silane: 3-aminopropyltriethoxysilane(APTES) Once cured, the surface amine (or epoxide) groups on HNTs will be covalently bonded with the epoxy matrix, allowing the HNTs to be integrated into the epoxy network. Such integration will enable the load to be fully transferred to the HNTs leading to significant stiffness/strength improvement. (Sun, L.; Warren, G. L.; O'Reilly, J. Y.; Everett, W. N.; Lee, S. M.; Davis, D.; Lagoudas, D.; Sue, H. J. Carbon 2008, 46 (2), ) Epoxy monomer Image- Mingliang Du,a,b Baochun Guob and Demin Jiab/ Newly emerging applications of halloysite nanotubes: a review Published online in Wiley Interscience: 12 January 2010 c 2010 Society of Chemical Industry

18 HNT Modification Procedure 2 ml of APTES dissolved in 25 ml toluene 0.6 g of clay Added to the suspension Sonicate for 30min refluxed at 120 C for 20 h under constant stirring Cite from Yuan, P.; Southon, P. D.; Liu, Z.; Green, M. E. R.; Hook, J. M.; Antill, S. J.; Kepert, C. J. J. Phys. Chem. C 2008, 112 (40), filtered & washed six times with resh toluene then dried at 120 C for 24 hrs

19 Future Work - Loading Nanotubes in Diluted epoxy or curing agent Vacuum removes air from lumens Above image -Abdullayev, et al. 17 copyright 2009 When vacuum is broken, epoxy components enter Acetone washing Dry loaded Nanotubes Self-healing implementation upon the rupture of HNTs Image-Sun, L.; Warren, G. L.; Davis, D.; Sue, H. J. J. Mater. Sci. 2011, 46 (1),

20 Thank You Q & A