Control of bending electrostriction in polyurethane films by doping with salt

We systematically investigated the effect of doping with salt on the bending electrostriction in polyurethane films. When a film was doped with sodium acetate, it was bent toward the cathode side by the application of an electric field. However, when a film was doped with zinc bromide, it was bent toward the anode side. Thus, we found a way of controlling the bending direction. We also investigated the mechanism of the effect of the doping. Doping is believed to be a treatment that can control the bending deformation through modification of the charge injection, the major origin of the deformation.