Degradable graft copolymers by ring-opening and reverse addition–fragmentation chain transfer polymerization

The synthesis and controlled ring-opening polymerization (ROP) of a six membered cyclic carbonate monomer with pendant reversible addition–fragmentation chain transfer (RAFT) functionality is reported. The growth of fast propagating monomers (methyl acrylate, tetrahydropyran acrylate and N-isopropylacrylamide) from the obtained RAFT-functional poly(carbonate)s resulted in the formation of well-defined graft copolymers with a biodegradable backbone, when grafting was terminated at low monomer conversions (ca. 30%). Direct dissolution of the thermally responsive poly(carbonate)-graft-PNiPAm copolymer yielded spherical micelles as confirmed by DLS and TEM analysis.