Polarization distributions in isotropic, stretched or annealed PVDF films

The time development of the polarization distribution across the film thickness in polyvinylidene fluoride (PVDF) was observed using the pressure step response technique. The crystallite phase composition of the samples was changed by annealing and stretching at elevated temperatures. It is shown that the crystallite phase composition, e.g., the beta crystallite content, determines the spatial distribution of the permanent polarization in PVDF.>