Electrostrictive Mechanisms in Polyurethane and Other Polymer Films

Electrostriction is the elastic deformation of a material caused by an electric field. Achievable deformations can be much larger than those of piezoelectric polymers and inorganic materials. Our research has focused on understanding electrostriction in thin polymer films - determining the underlying mechanism or mechanisms and the properties that control observed behavior. We have shown that experimental observations can be described as elastic deformation due to electrostatic forces. Critical to this conclusion has been correctly identifying the dielectric properties that govern electrostriction, and developing techniques to measure them. We have also developed a microscopic model for electrostriction of amorphous, polarizable solids. Model predictions agree very well with measured electrostriction parameters for a variety of polymer films.