Catalytic chemical recycling of biodegradable polyesters

The widespread utilization of plastics results in millions of tons of waste plastics being generated every year. During the last decade, converting waste plastics to valuable resources has been a primary objective for researchers in academia and industry. Nonetheless, most of the plastic recycling methods still rely on mechanical processes that are limited to relatively pure polymers; these mechanical processes generate end-products with lower thermo-mechanical properties. Therefore, tertiary recycling or chemical recycling methods are currently gaining more interest, mainly with conventional petroleum-based polymers. Recently some examples of catalytic chemical recycling have been described on biodegradable plastics, especially thermoplastics. Indeed, the recycling of biodegradable plastics helps to close the loop towards a lower environmental impact in the life cycle assessment of the material. The purpose of this review is to present the latest catalytic chemical recycling methods that were developed as solutions to the end of life management of biodegradable polyesters, with a focus on polylactic acid (PLA) and polyhydroxybutyrate (PHB).