Effect of the electrothermopolarization on the electret properties and the charge state of polyethylene nanocomposites with Cr and PbCrO4 additives

The results of studying the effect of electrothermopolarization on the electret properties and charge state of PE + Cr and PE + PbCrO4 composites are described. It is shown that an increase in the polarization field intensity to Ep = 5 × 106 V/m leads to an improvement in the polarization processes in the composites; at Ep > 5 × 106 V/m, the space charge concentration apparently increases, which results in the deterioration of the electret properties. The observed effect can be attributed to the repeated electron capture by deeper traps owing to the internal electric field. In addition, the intensity of the TSD peaks and therefore the number of stabilized charges for the composites polarized at high intensities are higher than for the samples polarized at low intensities.