Design and Control of Compostability in Synthetic Biopolyesters

The aerobic composting and anaerobic digestion of plastics is a promising route to recovering the multidimensional value from biodegradable single-use plastics. At present, the collection, separation, and management of biodegradable plastic waste are extremely challenging, and the majority of these plastics still end up in landfills or incineration facilities. This is because not all biodegradable plastics can be treated using organic waste management options (composting). In addition, end-users at a domestic and industrial level are often unaware of the compostability potential of biodegradable plastics, which results in the mismanagement of these types of plastic. A greater understanding of the compostability of biodegradable plastics will generate the required knowledge base for interventions that support their market penetration, use, and proper management. In this review, we clarify the concepts of biodegradability and compostability in bioplastics, in particular commercial synthetic biopolyesters, which have increasing technical and economic importance, and discuss how macromolecular design, blending, and additives can be used to modify their compostability. Future trends on the uptake of compostable and biodegradable bioplastics are also discussed.