Analysis of polarization and space charge in thermally poled PVDF

The spatial distribution of the space charge (SC) and polarization in thermally poled polyvinylidenefluoride (PVDF) can be studied using laser intensity modulation method (LIMM). The actual amount of charge existing in the poled specimen can be determined by hysteresis and thermally stimulated discharge current (TSDC) measurements. The hysteresis measurements are directly sensitive to polarization while the other method is sensitive to both the polarization and SC. PVDF is a ferroelectric polymer which contains polar crystals in which the direction of polarization can be reversed by an application of an appropriate electric field. It is interesting to try to determine the contribution of polarization charge and space charge to observed effects. Present work reports the results concerning the magnitude and spatial distribution of polarization/space charge in PVDF, determined from hysteresis, TSDC and LIMM measurements