HIGH-FIELD INDUCED ELECTRICAL AGING IN POLYPROPYLENE FILMS

Citation
D. Liufu et al., HIGH-FIELD INDUCED ELECTRICAL AGING IN POLYPROPYLENE FILMS, Journal of applied physics, 83(4), 1998, pp. 2209-2214
Citations number
30
Categorie Soggetti
Physics, Applied
Journal title
ISSN journal
00218979
Volume
83
Issue
4
Year of publication
1998
Pages
2209 - 2214
Database
ISI
SICI code
0021-8979(1998)83:4<2209:HIEAIP>2.0.ZU;2-J
Abstract
According to Kao's model of electrical discharge and breakdown in cond ensed insulating materials, charge carrier injection from electrical c ontacts and subsequent dissociative trapping, and recombination play a decisive role in the breaking of polymer chains and the creation of f ree radicals or low-weight molecules, and hence traps. We believe that electrical aging is due to this gradual degradation process. The incr ease in structural degradation and trap concentration reflects the deg ree of electrical aging and hence the lifetime of the electrically str essed polymers. On the basis of this concept, we have derived a theore tical formula for the prediction of the lifetime of insulating polymer s. We have also carried out experiments on polypropylene films at high electric fields. It is found that destructive breakdown occurs when t he accumulation of field induced traps reaches a certain critical valu e. Experimental results are in good agreement with our theoretical mod el. (C) 1998 American Institute of Physics.