Combined isothermal and non-isothermal techniques to analyze charge wrapping and stability in insulating materials

Taking into account the time-consuming trapping and detrapping of electric charge in insulating materials, a sequential protocol for the investigation the trapping sites and trapped charge stability is proposed.. The method i s demonstrated for Teflon FEP-A. Elemental peaks are obtained whose maxima shift with increasing field from 456 to 486 K and are characterized by acti vation energies that increase from 1.1 to 1.9 eV. The relaxation time of th e trapped charge, at 523 K, increases as the amount of charge stored in the material decreases and explains the good charge stability for Teflon FEP-A electrets.