Recycling of bio-based polyamides and polycarbonates

Transcription

1 Recycling of bio-based polyamides and polycarbonates Peter Sommer-Larsen, Danish Technological Institute, Plastics and Packaging Technology,

2 Recycling potential for three biopolymers Study performed under Dansk Materiale Netværks activity 5: Anvendelse af biobaseret plast til konstruktionsemner with Mia Katharina Podlech, DMN Sample preparation by Plast Center Danmark / testing by DTI Structures of biopolymers IS-PC Durabio 1720, Mitsubishi Chemical -[R]- being none or not disclosed n R m PA4.10 EcoPaXX Q-FP4, DSM PA6.10 GrilAmide XE 4073 Natural, EMS-Grivory NH NH NH NH n n

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4 Nylon properties Nylon 6.10 has lower moisture absorption than nylon 6 or nylon It is stronger than nylon 11, nylon 12, and nylon Nylon 6.10 retains its room temperature toughness at low temperatures better than nylon 6 or nylon 6.6. Nylon 6.10 has good resistance to most solvents and to dilute mineral acids. It also resists the environmental stress cracking action of salts such as zinc chloride Nylon 6.10 is priced higher than Nylon 6 Nylon 4.10 is greener according to DSM

5 Intro til resultater Virgin, recycled 1-10 cycles, steady composition S for steady composition: 70 % virgin +30 % recyclate 70 % virgin polymer 21 % 1 cycle 6 % 2 cycles 2 % 3 cycles 1 % 4 cycles. MFI [g 10 min -1 ] 24,0 22,0 20,0 18,0 16,0 14,0 12,0 Melt flow Rate IS-PC 10,0

6 PA6.10 PA % IS-PC 100 % Source: Nova Institute GmbH 2015

7 Recycling potential for three biopolymers Study performed under Dansk Materiale Netværks activity 5: Anvendelse af biobaseret plast til konstruktionsemner with Mia Katharina Podlech, DMN Structures of biopolymers PC Durabio 1720, Mitsubishi Chemical -[R]- being none or not disclosed PA 4.10 EcoPaXX Q-FP4, DSM PA 6.10 GrilAmide XE 4973 Natural, EMS-Grivory NH NH n R m NH NH n n

8 Melt flow index Methodology Melt Index Flow IS 1133 Granules Davenport MFR PC: 250 C and 1.2 kg PA: 275 C and 1.2 kg Mixing rule for viscosity i For the MFI of the S-composition before processing we use: ln( ) = ln ( ) and after processing: 4 =0 ln( ) = ln ( +1) 4 =0 Here the wn is the weight fraction of the n th cycle in the S-composition see above - and MFIn the corresponding MFI measured after that re-processing cycle. n=0 is the virgin, nonprocessed polymer. i Y. Song, P.M. Mathias, D.Tremblay, C.-C. Chen, Ind. Eng. Chem. Res. 2003, 42,

9 Melt flow index

10 A few results S for steady composition: 70 % virgin +30 % recyclate 70 % virgin polymer 21 % 1 cycle 6 % 2 cycles 2 % 3 cycles 1 % 4 cycles. Melt Flow index (MFI) turns out to be the most critical property for the evaluation of re-processability Polymer Average MFI increase per cycle Numbers of cycles to exceed 20% increase from virgin Numbers of cycles to exceed 40% increase from virgin IS-PC 4 % 5 8 PA % 3 8 PA % 2 2 Table 2: Relative increase in MFI per cycle and the number of cycles it takes to exceed at 20 % or 40 % increase over the MFI of the virgin polymer

11 A few results S for steady composition: 70 % virgin +30 % recyclate 70 % virgin polymer 21 % 1 cycle 6 % 2 cycles 2 % 3 cycles 1 % 4 cycles. No major changes in their mechanical properties.

12 A few results Charpy impact test IS single notched specimen Notch type: 1eA Zwick & Co KG, Pendelschlagwerk 40/10/5 kg Pendulum: 10 kpcm S for steady composition: 70 % virgin +30 % recyclate 70 % virgin polymer 21 % 1 cycle 6 % 2 cycles 2 % 3 cycles 1 % 4 cycles. Impact strength for PA 4.10 and IS-PC decreases to a plateau value with cycle number

13 A few results DSC IS Granules Mettler Toledo DSC 823 TGA IS Granules Mettler Toledo TGA/SDTA 851 S for steady composition: 70 % virgin +30 % recyclate 70 % virgin polymer 21 % 1 cycle 6 % 2 cycles 2 % 3 cycles 1 % 4 cycles. No change for PA Virgin IS-PC deviates

14 A few results DSC IS Granules Mettler Toledo DSC 823 TGA IS Granules Mettler Toledo TGA/SDTA 851 S for steady composition: 70 % virgin +30 % recyclate 70 % virgin polymer 21 % 1 cycle 6 % 2 cycles 2 % 3 cycles 1 % 4 cycles. DSC 1 st heating: -40 o C to 300 o C, N 2 at 10 o C/min, hold 2 min DSC Cooling: 300 o C to -40 o C, N 2 at 10 o C/min, hold 5 min DSC 2 nd heating: -40 o C to 300 o C in N 2 at 10 o C/min PA 6.10 virgin deviates for Tg First cycles deviates for IS-PC Tg

15 A few results FTIR ATR Granules Thermo Scientific is50 FT-IR S for steady composition: 70 % virgin +30 % recyclate 70 % virgin polymer 21 % 1 cycle 6 % 2 cycles 2 % 3 cycles 1 % 4 cycles. xidative degradation mechanism (after Goncalves et al) normalize all spectra to the same absorption for the peak at 930 cm -1. Does not work well with ATR

16 A few results FTIR ATR Granules Thermo Scientific is50 FT-IR S for steady composition: 70 % virgin +30 % recyclate 70 % virgin polymer 21 % 1 cycle 6 % 2 cycles 2 % 3 cycles 1 % 4 cycles cm-1: Imide group

17 A few results FTIR ATR Granules Thermo Scientific is50 FT-IR S for steady composition: 70 % virgin +30 % recyclate 70 % virgin polymer 21 % 1 cycle 6 % 2 cycles 2 % 3 cycles 1 % 4 cycles cm -1 CH2-NH (amorphous) Decrease expected for chain scission 1140 cm -1 C- deformation (amorphous) 935 cm -1 C-C stretch (crystalline)

18 Conclusions The projects aims at determining the number of times each of the three polymers may be reprocessed into recyclates. The conclusion for the results presented above is IS-PC: recycle up to 5 times S-composition is comparable to the virgin polymer in all aspects PA4.10 does not recycle well. Most properties degrades over the first few cycles. PA6.10: recycle up to 3 times S-composition will for all practical purposes substitute the virgin polymer The data does not support a specific degradation mechanism, but increase in MFI show that the average molecular weight does decrease over re-processing cycles.

19 Suppliers Some suppliers and Danish agents for bioplastics Type Grade Supplier DK Repr. PLA / polyester Bio-Flex FKuR FKuR SE / PolymerFront SE PE LLDPE / HDPE Braskem Braskem Europe GmbH / PolymerFront SE TPU PearlThane EC Lubrizol Bjørn Thorsen A/S PA 6.10 GrilAmide EMS-GRIVRY Erteco Rubber & Plastics AB PA 4.10 Ecopaxx DSM RESINEX Denmark A/S DSM Scandinavia PA 6.10 / Zytel Dupont Distrupol Nordic PA 11 Rilsan Arkema RESINEX Denmark A/S PA 61.0 Ultramid Balance BASF BASF Denmark PA 6.10 / / /12(?) Vestamid Evonik Brenntag

20 Biobased / biodegradable / Plastics? Standards / Technical Specifications CEN/TR 16208:2011 Biobased products - verview of standards ( ) CEN/TR 15932: 2010 Plastics - Recommendation for terminology and characterisation of biopolymers and bioplastics ( ) CEN/TS 16137:2011 Plastics - Determination of bio-based carbon content ( ) CEN/TR Liquid petroleum products Biolubricants Recommendation for terminology and characterisation of bio-lubricants and bio-based lubricants ( ) CEN/TS Plastics Determination of bio-based carbon content ( ) CEN/TS Plastics - Template for reporting and communication of bio-based carbon content and recovery options of biopolymers and bioplastics - Data sheet ( ) EN 13432:2000 Packaging - Requirements for packaging recoverable through composting and biodegradation - Test scheme and evaluation criteria for the final acceptance of packaging EN 14995:2006 Plastics. Evaluation of compostability. Test scheme and specifications