Hydrogels composed of poly(vinyl alcohol) (PVA) and poly(N-isopropylacrylamide) (PNIPAAm) was prepared by the sequential-interpenetrating polymer network (IPN) method. The equilibrium swelling ratio and bending behavior under electric fields of the IPN hydrogel were measured in aqueous NaCl solution. The IPN exhibited a high equilibrium swelling ratio, in the range 280~380%. When the IPN in aqueous NaCl solution is subjected to an electric field, the IPN showed significant and quick bending toward the cathode. The IPN hydrogel also showed stepwise bending behavior depending on the electric stimulus. In addition, ionic conductivity of the IPN hydrogel was measured using dielectric analysis (DEA). The ionic conductive behavior of IPN hydrogel follows the Arrhenius equation. The conductivity of IPN hydrogel and the activation energy for the form of the IPN were 1.68 ×10^-5 S/cm at 36 °C and 61.0 kJ/mol, respectively.

Date Published: 24 April 2003
PDF: 9 pages
Proc. SPIE 5116, Smart Sensors, Actuators, and MEMS, (24 April 2003); doi: 10.1117/12.498713

Published in SPIE Proceedings Vol. 5116:
Smart Sensors, Actuators, and MEMS
Jung-Chih Chiao; Vijay K. Varadan; Carles Cané, Editor(s)