Synthesis Of Poly(vinyl Acetate) Block Copolymers By Successive Raft And Atrp With A Bromoxanthate Iniferter

摘要

Poly(vinyl acetate)-b-polystyrene, poly(vinyl acetate)-b-poly-(methyl acrylate) and poly(vinyl acetate)-b-poly(methyl metha-crylate) block copolymers with low polydispersity (M_w/M_n < 1.25) were prepared by successive reversible addition-fragmentation chain transfer (RAFT) polymerization and atom transfer radical polymerization (ATRP) employing a bromoxanthate iniferter (initiator-transfer agent-terminator).rnBlock copolymers have attracted increasing attention due to their unique properties and utility in many applications. Controlled radical polymerization is a versatile tool for the synthesis of a variety of block copolymers. Among these methods, RAFT and ATRP have emerged as the most successful techniques due to their applicability to a wide range of monomers and mild reaction conditions. Although the CRP of many vinyl monomers is very effective, the preparation of well-defined block copolymers from both conjugated and non conjugated monomers remains challenging. Indeed, RAFT agents suitable for styrenic and (meth)acrylic monomers provide poor, or no control, over the polymerization of vinyl acetate (VAc) or N-vinylpyrrolidone (NVP) and vice versa.