Anomalous recovery of the remanent polarization after heating polarized PVDF films up to 180°C

Abstract

Biaxially stretched 38-μm-thick PVDF (polyvinylidene fluoride) samples with about 80% β content were poled at room temperature at E=200 MV/m for 5 s. The remanent polarization was measured with the PPS method first at 20°C, then after heating to 180°C, and a third time after cooling the sample to room temperature again, to determine its temperature-dependent stability. To distinguish between irreversible and reversible polarization loss due to heating of polarized PVDF films, the polarization was measured at elevated temperatures and after cooling down to room temperature again. The reversible polarization loss causes the pyroelectricity of PVDF.