CHARGING AND DISCHARGING CURRENTS IN POLYVINYLALCOHOL (PVA) POLYMER-FILMS

Charging and discharging currents in polyvinylalcohol (PVA) polymer fi lms were measured over the temperature range 30-150 degrees C and fiel d strengths of (2.3-23)X10(6) V m(-1). Polymer films were prepared by the isothermal immersion technique. The effect of field strength and c harging temperature on the transient currents was studied. Activation energies were evaluated from quasi steady state currents. A single rel axation peak was observed both from isochronal currents and low-freque ncy dielectric relaxation. Activation energies evaluated from both the se methods are found to be in fairly good agreement. The polarization has been considered to be due to space charge origin along with some c ontribution from dipolar groups.