Biobased Synthesis and Biodegradability of CO₂-Based Polycarbonates

Stimulated by the growing interest in sustainable polymers, the past few decades have seen intensive research in the field of CO₂-based polycarbonates. Within this research, the catalysts for the ring-opening copolymerization of epoxides and CO₂ developed from early heterogeneous complexes to a wide variety of homogeneous catalysts. These complexes are continuously improved to meet growing expectations regarding activity and selectivity. Simultaneously, the range of epoxide monomers has steadily expanded due to the growing interest in biobased starting materials for polymers. The potential of the resulting aliphatic polycarbonates is evident in their thermal and mechanical properties, where they exhibit a wide range from soft to brittle and from low to high glass transition temperatures. Although the biodegradability of CO₂-based polycarbonates has not yet been extensively researched, it has already been possible to gain knowledge about poly(propylene carbonate) and its compostability. The entire potential of aliphatic polycarbonates is still far from being fully discovered, and with constant development of new catalysts and monomer feedstocks, the chance of a CO₂- and biobased polymer achieving greater industrial relevance is increasing.