Thermally Stimulated Discharge of Polymer Electrets

A special form of depolarization of polymer electrets is described: the thermally stimulated discharge (TSD). After reviewing its principles and exposing its mathematical analysis, results are presented which show that TSD is a powerful method to gain insight into the molecular mechanisms of the electret effect. In fact, TSD reveals all low-frequency molecular motions. It enables one to determine, e.g., the glass-rubber transition of polymers. Its merits are compared with those of isothermal dielectric, and mechanical methods of investigation.

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