Synthesis of novel polymers with biodegradability from propylene and carbon monoxide

Developing novel polymers with biodegradability could mitigate polymer-related pollution. Here, polymers containing ester and ketone groups with moderate biodegradability (regardless of their chirality) were synthesized from poly(propylene-alt-carbon monoxide)s by the Baeyer–Villiger oxidation with aqueous H2O2 and AlCl3 (which increased the ester content of the as-synthesized polymers to >35 mol%). The ester groups in these polymers, showed two isomeric structures (originating from two oxygen-atom insertion modes), and 70% of the ester groups were structurally same as those in P3HB (a common biodegradable polymer). Additionally, solvent-cast blended films comprising these polymers and poly(L-lactic acid) showed a higher strain at break than pure-poly(L-lactic acid) films. Therefore, this study proposes a cost-effective strategy for the synthesis of biodegradable polymers that can be used as plasticizers of poly(L-lactic acid), facilitating a wide range of applications.