Characterization of aging in polymeric insulation by thermally stimulated depolarization current measurements

The authors present the characterization of aging in polymers used for outdoor high-voltage insulation by the thermally stimulated depolarization (TSD) current technique. The materials evaluated include new, artificially aged and naturally aged samples of high-temperature-vulcanized (HTV) silicone rubber and ethylene-propylene rubber. Results of this technique are compared with the data obtained from techniques such as crossover voltage measurement (COV), energy dispersive X-ray (EDX) studies X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). It is shown that TSD can provide information at the molecular level which relates to aging.<>