US Patent 7179872 Chain transfer agents for RAFT polymerization in aqueous media

Polymers and copolymers synthesized by means that yield a narrow range of molecular weights can have different properties than polymers synthesized by conventional means. In order to obtain such polymers, however, polymerization must be controlled. One type of controlled polymerization is the reversible addition-fragmentation chain transfer (RAFT) process, which has characteristics of a living polymerization. The present invention discloses a group of dithioesters and trithioesters suitable as chain transfer agents for RAFT polymerization. The present invention also discloses RAFT polymerizations conducted in aqueous media.