On the determination of electrical conductivity in polyethylene

Abstract
There are significant differences in the field dependence of conductivity in low-density polyethylene as reported by various investigators. These differences are attributable partly to the presence of different kinds of impurities in variable concentrations in polyethylene samples of various origin, but are mainly due to the different measurement procedures adopted. The significance of the time which elapses after the application of voltage to the electrodes, as well as the effect of conditioning, e.g. thermal and voltage stressing of the specimen before and during the measurement, is discussed. Whether it is always necessary to obtain a steady-state current in order to determine the true conductivity is somewhat debatable.