Electromechanical studies of a novel polymer gel

Elastic films (thickness ca. 200 {mu}m) of water-swollen, sulfonated styrene/ethylenelbutylene/styrene triblock polymers (14-69% of the styrene sulfonated) were investigated for their ability to exhibit bending movement in electric fields. Application of electric fields of 1-8 V/cm afforded relatively rapid bending of the films toward the cathode. The gel bending dependence on the solution concentration was studied and a maximum was found at about 0.02 M Na{sub 2}SO{sub 4}, while the swelling kept decreasing with increasing concentration. Bending and swelling increased with the degree of sulfonation. When the applied field strength increased, the bending increased and eventually leveled off although the current continued to increase. Switching of the field direction every few seconds resulted in continuous reversals in the direction of film bending.