RAFT polymerization and thiol chemistry: A complementary pairing for implementing modern macromolecular design

Abstract

Reversible addition fragmentation chain transfer (RAFT) polymerization is one of the most extensively studied reversible deactivation radical polymerization methods for the production of well-defined polymers. After polymerization, the RAFT agent end-group can easily be converted into a thiol, opening manifold opportunities for thiol modification reactions. This review is focused both on the introduction of functional end-groups using well-established methods, such as thiol-ene chemistry, as well as on creating bio-cleavable disulfide linkages via disulfide exchange reactions. We demonstrate that thiol modification is a highly attractive and efficient chemistry for modifying RAFT polymers. The versatility of thiol chemistry on RAFT-prepared polymers is reviewed. Methods producing stable thioether bonds as well as (bio-)degradable disulfide bonds are presented. These methods are highly useful to introduce functional or reactive end-groups into polymers and to build up (degradable) nano-structures for drug delivery purposes. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.