One stone two birds: from one azlactone-functionalized monomer to a heterofunctional diblock copolymer

Abstract

Demonstrated is the successful implementation of a novel route for the preparation of heterofunctional diblock copolymers derived from 2-vinyl-4,4-dimethyl azlactone (VDM) by sequential reversible addition–fragmentation chain transfer (RAFT) polymerization and post-polymerization modification (PPM). The relevance of the sequence is demonstrated using as starting material a copolymer of VDM and N,N-dimethylacrylamide (DMA) prepared by redox-initiated RAFT polymerization at room temperature. By using an equimolar ratio of amine to azlactone groups during the first PPM, the thiocarbonylthio chain end survives the click aminolysis and the resulting copolymer can then be extended with a second block containing VDM. Subsequent PPM with a second amine yields a diblock copolymer with a unique VDM-derived backbone in both blocks, which differ only in the nature of the side chains.