New publication in Environmental Science and Technology systematically describes the effect of polymer properties on the biodegradation of polyurethane microplastics


Currently available polyurethanes are not (yet) biodegradable and should therefore be recycled, but unintentionally released microplastics from these materials might end up in the environment. However, the functional groups contained are sufficiently hydrolysable to enable at least partial biodegradation via enzymatic processes. In this study it was found that the polymer backbone, crystallinity and additives influence conversion into CO2 and fragmentation. Biodegradation up to 72 % was achieved for the investigated polyurethanes in compost. The degradation mechanism is based on surface erosion and fragmentation within the outermost aged particle layers. The results help to gain a mechanistic understanding of polyurethane microplastic biodegradation when unintentionally released into the environment and also support enzymatic recycling strategies for this material class.