Mukherjee et al presented the preparation of dynamic star shaped polymers using oximes as reversible links.
Summerlin and his co-workers have demonstrated the formation of oxime-functional macromolecular stars that are able to dissociate and reconstruct themselves upon application of a stimulus. The reversible nature of the oxime bond in the presence of externally added alkoxyamines or carbonyl compounds enables reconfiguration via competitive exchange. Reversible addition–fragmentation chain transfer (RAFT) polymerization was utilized to prepare well-defined amphiphilic block copolymers in which a hydrophobic keto-functional block allowed self-assembly into micelles in water. Adding a difunctional alkoxyamine small molecule to these solutions resulted in crosslinking of the micelles to yield macromolecular stars. The reversible nature of the O-alkyl oxime linkages was demonstrated via competitive exchange with excess of carbonyl compounds or monofunctional alkoxyamine under acidic conditions and at elevated temperatures to result in dissociation of the stars to unimolecular oxime-functional polymer chains.
Oximes as reversible links in polymer chemistry: dynamic macromolecular stars by Soma Mukherjee, Abhijeet P. Bapat, Megan R. Hill and Brent S. Sumerlin Polym. Chem., 2014,5, 6923-6931.
Remzi Becer is a web-writer and advisory board member for Polymer Chemistry. He is currently a Senior Lecturer in Materials Science and the director of the Polymer Science and Nanotechnology masters programme at Queen Mary, University of London. Visit www.becergroup.com for more information.
