Poly(2-oxazoline)s and click chemistry: A versatile toolbox toward multi-functional polymers

Poly(2-alkyl/aryl-2-oxazoline)s (PAOx) have been gaining increasing attention because they combine biocompatibility with so-called stealth behavior, making them ideal candidates for use in a wide variety of biomedical applications. Especially, the possibility of side-chain modification makes them a valuable alternative to poly(ethylene glycol), currently the gold standard amongst biocompatible polymers. Nevertheless, the cationic ring opening polymerization of 2-oxazolines is not compatible with nucleophilic entities, for example hydroxyl and amine moieties. Therefore, the modular approach of 'click chemistry' offers an elegant strategy toward functional PAOx by post-polymerization modification of PAOx that contain clickable groups. This feature describes the synthesis of PAOx with such clickable entities at the chain-end or in the side-chain, as well as their potential (bio)materials applications. (C) 2015 Elsevier Ltd. All rights reserved.