Rapid response of a poly(acrylamide) hydrogel having a semi-interpenetrating polymer network structure

Responsiveness of a poly(acrylamide) (PAAm) hydrogel having a semi‐interpenetrating polymer network (semi‐IPN) structure was compared with that of a PAAm normal‐type hydrogel in acetone/water mixtures. The PAAm semi‐IPN hydrogel shrank much more rapidly by changes in the acetone concentration than the PAAm normal‐type hydrogel though there was no difference in their equilibrium swelling ratio between them. This suggests that the introduction of a semi‐IPN structure into a hydrogel enhances its responsiveness very easily. Copyright © 2006 John Wiley & Sons, Ltd.