Addition-Fragmentation Ring-Opening Polymerization of Bio-Based Thiocarbonyl l-Lactide for Dual Degradable Vinyl Copolymers.

This study is designed to synthesize novel degradable polymers by radical addition-fragmentation ring-opening copolymerization of bio-based thiocarbonyl compounds with various vinyl monomers. Thiocarbonyl l-lactide is capable of radical copolymerization with acrylates and styrene via radical addition to the carbon-sulfur double bonds followed by ring-opening as well as controlled copolymerization in conjunction with the reversible addition-fragmentation chain transfer (RAFT) process. The obtained polymers possess ring-opened thioester and ring-retained thioacetal functionalities in the backbone, both of which could be cleaved under appropriate conditions with different chemical stimuli.