Filamentary electromechanical breakdown in polymers

Some early models of breakdown in polymers are reviewed. The proposal of H.R. Zeller et al. (1984) of electrofracture as an aging mechanism in which the growth of a filamentary (i.e. tubular) crack through a dielectric is caused by electrostatic forces is discussed, and the nature of filamentary electromechanical breakdown is examined. Experimental results in support of the filamentary model are summarized. It is concluded that electromechanical breakdown at least contributes to breakdown in many polymeric systems, particularly those involving thin films where a small deformation gives rise to a sharp increase in electric field