2017 has been the year when the momentum for measures to make plastic production more circular seems unstoppable. The UN recently passed a resolution to stop plastic waste entering the oceans and Europe will soon publish its strategy to bring Circular Economy principles to the plastics supply chain. This drive to make it less attractive to dispose of waste plastics in landfill or by incineration is good news, but how will it impact on the market for bioplastics?
Europe’s strategy is to give value to waste plastic, especially packaging, and to create a market for recycled plastic. Publication of the strategy is now expected in January but an early leaked draft was ambivalent about bioplastics, particularly biodegradable ones. Consumer brands however are still interested in bioplastics. Braskem recently announced another new customer for its bioPE packaging and the recent European Bioplastics Conference revealed evermore new products made with bioplastics.
Recycling plastic is complicated because there are so many types of plastic in use: PE, PP, PET, ABS, PVC, PS to name some of the main ones. Waste plastic must be sorted by type before it can be recycled and then each type needs to be sorted by colour to maximize the utility of the waste. It makes sense therefore to minimize the number of different plastics in circulation to reduce complexity in sorting. Biodegradable plastics like PLA and PHAs are different chemically from established plastics so have to be separated out from mixed waste. They are very small components of the overall plastic mix therefore it is less worthwhile investing in technology to separate them.
A move to reduce the variety of plastics in use means that PLA and PHAs are most suited to applications where biodegradability is the best solution to the problem of waste. Applications like fishing nets and other marine articles and agricultural mulch films are ideal for plastic that ends its life in the sea or on land. However these are niche applications and producers are really looking to enter the bigger markets of food packaging and disposable cutlery. There is an argument that much food packaging is too contaminated to recycle and that it will be easy for consumers to recycle food waste with its packaging. But the compostability of PLA varies and there is pressure to keep all but the thinnest bags out of the composting supply chain. The consensus in Switzerland for example, is that thicker items like disposable cutlery and plates made from PLA can only be composted as part of a closed system e.g. disposable cutlery from an event where agreed composting arrangements are in place.
Drop-in, non-biodegradable biopolymers, like bioPE, are chemically identical to their fossil counterpart, so they can be recycled in the same stream. Bio PET from drinks bottles is recyclable with fossil PET. However higher cost still limits their use. It will be interesting to see if European measures, like producer responsibility, will add costs to the fossil plastic supply chain such that the gap between fossil and bio drop-ins is narrowed.
So the strong drive for more recycling of fossil plastic may favour drop-in bioplastics over biodegradables. However in 2018 the public’s attention is likely to be drawn to an environmental challenge that can best be solved using biodegradable plastic. The focus on marine pollution will highlight the dangers from non-biodegradable fibres from clothes. These plastic fibres end up in the sea and the food chain. Biodegradable fabrics could therefore be the new market that brings hope to the industry in 2018. So society’s New Year’s resolution to recycle waste plastic may still boost demand for bioplastics.
Published: 12 December 17
