Influence of aging on electrical properties of polyethylene naphthalate-2,6 dicarboxylate films

Poly (ethylene naphthalate 2,6 dicarboxylate), thanks to its heat resistanc e, may be used as insulating material in motors and laminated chip capacito rs. In these specific applications the occurrence of partial or corona disc harges leads to insulation aging and possible breakdown. An experimental in vestigation has been carried out to determine the changes in dielectric pro perties as function of the aging conditions, e.g the temperature of irradia tion. Dielectric loss values have been determined in the 10(2) to 10(6) Hz frequency range from 150 to 200 degrees C. Three relaxation peaks were foun d alpha, beta*, beta, in the order of decreasing temperature.