On the Nature of Poling by Corona Charging and the Pyroelectric Effect in PVF2

The effect of corona charging (at 12.5 kV) of polyvinylidine fluoride (PVF
2
) is studied by infrared spectroscopy and X-ray diffraction techniques. The results show that changes in molecular conformation occur with such a poling process that is in agreement with Southgate. The pyroelectric coefficient was observed to increase significantly after such a poling, reaching a maximum value of ~3 nC/cm2K at ~343 K. It is suggested that the pyroelectricity in PVF2 at this temperature is due to dipolar orientation.