DC conduction current and voltage endurance of polypropylene film

In this paper the effect of temperature and electrode material on the charging and discharging current and DC voltage endurance of a biaxially orientated polypropylene film have been investigated. The charging current was found to be dependent of electrode material, suggesting that the current was controlled by electrode processes. The charging current was found to strongly increase when increasing the temperature for 20 to 60/spl deg/C. The level of the discharging current was low and for the higher applied stresses and temperatures the discharging current flowed in the direction of the charging current, thus indicating a build up of space charge in the film. DC voltage endurance tests revealed that there was no significant dependence of electrode material. Increasing the temperature from 20 to 60/spl deg/C resulted in a significantly reduced endurance.