Thermostimulated depolarization currents in thermally aged polyethylene terephthalate (PET) films

Thermal aging of the polyethylene terephthalate film influences its thermostimulated depolarization current spectra. The dynamics of the process was studied. Of the three major relaxation mechanisms occurring, the space charge relaxation, appearing above 380 K, shows a complex and strong dependence on the temperature and time of aging. This dependence can also be related to changes of other macroscopic properties of the film.<>