Bio-based PHA copolymers as enhancers of properties of recycled PVC Yelena Kann, PhD October 21-23, 2013 Iselin, NJ SPE Vinyltec 2013,
Metabolix Vision Bio-Industrial Evolution Through bioscience and engineering, we bring clean, sustainable, and economically viable solutions to the world in plastics, chemicals, and energy. 2
Metabolix Core Capabilities Industrial Biotechnology Leader Two Primary Pathways Metabolic Engineering Multi-gene Expression Analytical Expertise Process Engineering Polymer Science & Product Dev. PHAs: Nature s Versatile Family of Storage Materials Fermentation Two Primary Pathways Efficient Recovery Process Industrial Crops Over 500 Patents Issued & Pending Integrated Value Chain based on Metabolix PHA Core Competency 3
Polyhydroxyalkanoate (PHA) Vinyltec 2012 and ANTEC 2013: presented data on miscibility of PHA and PVC and on impact modification and plasticization; New data: PHA as enhancer of recycled PVC properties PHA copolymers: Rigid Glass temperature 10 C Melting temperature 180 C Young s modulus 2.5 GPa Elongation at at break 3 % Flexible - 50 C 60 C 0.2 GPa 1000 % 4
Recycling of PVC Rapid growth of the PVC waste of the short-life (packaging, bottles, medical devices) and long-life products (pipes, window frames, cable insulation, floors covering, roofing sheets, siding, etc.) As a result, more PVC is entering the waste stream; PVC waste: landfilling (very expensive and no longer acceptable in many countries) energy recovering (incineration) material recovering (chemical and mechanical recycling) 5
Recycling of PVC (cont.) Since 1980s steady increase in the recycling rates; new recycling programs developed (Vinyl 2010, Europe: ~195 Ktonnes of PVC were recycled in 2008) In 2010 globally ~ 1.4 mln tonnes recycled via mechanical methods PVC is now one of the largest recycled polymer by volume in developed countries Germany is the most advanced in PVC recycling 6
Recycling of PVC (cont.) Areas of activities in PVC recycling: 1. Development of techniques and instrumentation for separation of PVC from waste stream 2. Improvement of current methods and/or development of new methods for recycling of PVC waste 3. Improvement of compatibility of recycled PVC with other polymers and virgin PVC 4. Recycling of mixed PVC waste 5. Development of new energy recovery techniques 6. Recycling of post consumer PVC waste through specific projects 7. Improvement of physical and mechanical properties of recycled PVC 8. Survey on the effect of multiple recycling 7
Properties of PVC Recyclate/PHA 90A Medical grade recycle/i6003rp PHA % PHA 0 10 15 20 Modulus, MPa 24.47 14.86 18.28 34.96 Tensile stress at Yield, MPa 13.02 13 11.6 18.36 Tensile strain at Break, % 101.08 145.64 154.92 210.52 Tensile toughness, J 0.77 1.04 1.10 1.78 tear, N/mm 34.7 31.6 36.1 46.5 92A General grade, flexible recycle/i6003rp PHA % PHA 0 10 15 20 Modulus, MPa 28.54 22.92 62.01 64.44 Tensile stress at Yield, MPa 16.16 17.5 14.48 16.07 Tensile strain at Break, % 157.6 252.9 178.3 195.4 Tensile toughness, J 1.60 2.67 2.37 2.23 tear, N/mm 39.76 39.79 52.09 46.07 8
Properties of Recyclate PVC/PHA 9
Properties modification, semi-rigid PVC (86D) 10
Melt Rheology of Recyclate PVC/PHA PHA stabilizes PVC against cross-linking: the slopes of melt viscosity are reduced in the presence of PHA 11
Melt Rheology of Recyclate PVC/PHA (cont.) Melt viscosity (MV) is reducing due to the plasticization of PHA, not thermal degradation. TGA confirms this: % I6003rp PHA 0 10 15 20 TGA, 5% loss, C 264 269 269 269 max dw/dt, C 295 300 302 302 12
Mixing scrap with virgin PVC, flexible grades I6003rp PHA Loading, % 0 0 15 15 PVC mixed color scrap, % 96A durometer 100 50 50 85 Virgin PVC stabilized compound, % 90A durometer 0 50 35 0 Durometer, A 66 61 63 Bad quality Tensile toughness, J 1.15 2.86 2.99 sample Tensile strength, MPa 12.85 20.6 23.3 13
Conclusion PHA copolymers, being polymeric and very miscible with PVC, repair and upgrade physical properties of PVC recyclates; PHA copolymers improve compatibility of PVC recyclates (different sources, hardnesses) and virgin PVC. Replace virgin PVC and improve recovered properties The thermal stability of recycled PVC is improved in the presence of tested PHA copolymers: the melt viscosity stabilizes in the presence of PHA and does not show the tendency to increase with prolonged exposure to the processing conditions The non-migrating, non-toxic and bio-based PHA copolymers promote higher preconsumer/postconsumer PVC scrap utilization and formulation of reusable feedstocks with quality rivaling that of new resin 14