A model of aging of dielectric extruded cables

The authors present a model of electrical aging of extruded cables based on actual data and realistic experimental conditions. It is shown that a simple model partially based on the rate theory associated with the name of Eyring describes very well the aging of polyethylene (PE), crosslinked PE, and ethylene-propylene rubber cables under a wide variety of conditions. The significance of the physical and thermodynamic parameters used in the model is discussed in relation to the polymer morphology. It is speculated that severe and irreversible electric aging of dielectrics is preceded by the formation of microcavities in the 50-100-AA range.<
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