THERMOSENSITIVE AND REDOX-ACTIVE POLYMERS - PREPARATION AND PROPERTIES OF POLY(N-ETHYLACRYLAMIDE-CO-VINYLFERROCENE) AND POLY(N,N-DIETHYLACRYLAMIDE-CO-VINYLFERROCENE)

Thermosensitive and redox-active polymers were prepared by copolymeriz ation of N-ethyl- or N,N-diethylacrylamides with vinylferrocene (VFc). LCST (lower critical solution temperature) of the aqueous copolymer s olution was decreased by increasing the ferrocene content in the copol ymer. The oxidation of ferrocene led to a significant increase in LCST due to the transition from hydrophobic to hydrophilic character of th e ferrocene moiety in the copolymer. The ferrocene content in the copo lymer increases with increasing differences between the LCST's of the oxidation and reduction states. The transition could be made reversibl e by redox reaction using L-ascorbic acid as an oxidant and cerium sul fate as a reductant. (C) 1997 John Wiley & Sons, Inc.