New Developments in Charging and Discharging of Polymers

In this paper we present an overview of new developments in the field of charge storage and transport in insulating polymeric materials. We briefly scan new techniques for charging, such as the Constant-Current-Corona, a technique for positively charging with an electron beam, and a new technique to measure spatial charge distributions. In addition, we present results for the charging behavior and charge transport of selected polymers, such as Teflon ®, poly(ethylene terephthalate) and poly (vinylidene fluoride). For Teflon, recently obtained spatial charge distributions measured for various experimental conditions are compared with older results and show basic agreement. For poly(ethylene terephthalate) a dipole-space charge interaction is found which shows alignment of dipoles in the field of the space charge during a thermally stimulated experiment. In addition, the disappearance and reappearance of a dipole related TSC peak is reported and explained by the free volume concept. For poly(vinylidene fluoride) two models are presented that describe the dynamics of the high field poling process when poling with different external resistances in the measuring circuit. Both models have the ability to describe the experimental results quantitatively.