Reversible addition-fragmentation chain transfer (RAFT) radical polymerization and the synthesis of water-soluble (co)polymers under homogeneous conditions in organic and aqueous media

Reversible addition-fragmentation chain transfer (RAFT) radical polymerization has, since its discovery by CSIRO, evolved into an extremely powerful synthetic tool for polymer chemists. The versatility of RAFT, with respect to reaction conditions and monomer class, now facilitates the preparation of materials which, only 10 years ago, could not be prepared with well-defined molecular characteristics. One particularly advantageous feature of RAFT is its applicability to the synthesis of water-soluble (co)polymers both directly in aqueous media under homogeneous conditions as well as in organic media. The ease of access to an almost infinite number of RAFT mediating agents now affords the synthetic chemist the ability to polymerize virtually any activated, and some non-activated, water-soluble/hydrophilic monomers. We highlight herein the application of RAFT to the synthesis of water-soluble/dispersible (co)polymers under homogeneous reaction conditions in both aqueous and organic media. Additionally, we review the aqueous solution properties of advanced stimuli-responsive systems with a particular emphasis on the stimulus-induced, and often reversible, supramolecular self-assembly characteristics of the materials. Limitations of homogeneous aqueous RAFT are also highlighted. (c) 2006 Elsevier Ltd. All rights reserved.