Effect of temperature on electroactive films of cellular polypropylene

We report the effect of temperature on the magnitude of the d/sub 33/ coefficient of cellular polypropylene films. We have also measured the short-circuit, thermally-stimulated-current from poled samples as well as the dependence of complex capacitance on temperature at frequencies around the thickness-mode resonance. We conclude that the thermal stability of the piezo properties depend on both the electrical and mechanical properties of the material.