Vinyl Copolymers with Faster Hydrolytic Degradation than Aliphatic Polyesters and Tunable Upper Critical Solution Temperatures

Radical ring-opening polymerization (rROP) of cyclic ketene acetals (CKAs) is considered the most promising approach to impart degradability to vinyl polymers. However, rROP-synthesized materials still exhibit poor hydrolytic degradation and thus cannot yet compete with traditional polyesters. Here we show that a simple copolymerization system based on acrylamide and CKA can lead to well-defined copolymers with faster hydrolytic degradation than that of polylactide and poly(lactide-co-glycolide). Moreover, by changing the nature of the CKA, the copolymers were either water-soluble or exhibited tunable upper critical solution temperatures (UCST) relevant for mild hyperthermia-triggered drug release. To illustrate the interest of these new copolymers, we showed that they were cytocompatible on different cell lines and we synthesized amphiphilic diblock copolymers that were formulated into UCST nanoparticles by an all-water nanoprecipitation process. We anticipate this copolymerization system to offer new avenues in different applications such as biodegradation of commodity polymers, drug delivery or tissue engineering.