Surface potential on LDPE film due to residual charges

The authors showed that the polarity of the surface potential was always the same as that of the applied voltage. The potential tended to increase to a constant value of about 650 V with increasing the applied voltage and application time for both polarities and both specimens. However, the increase in the short-circuiting time tended to increase the potential on only the low density polyethylene (LDPE) for both polarities, while it did not change that on PP at all. The effect of longer short-circuiting on the increase in the surface potential on the LDPE films for both polarities could be explained by the return of injected charges to the source electrode during the short circuiting period