Morphology of thermoplastic and cross-linked polyethylene cable insulation

The following conclusions can be drawn: 1. The study of void population, size, and mobility will help define mechanisms of electrical failure in polyethylene cable insulation. Structural models explaining the origin of voids in terms of spherulitic domains must be expanded to include nonspherulitic morphologies. 2. Sample preparation for SEM investigations is extremely important. The actions of any etching procedure used in surface preparation must be carefully characterized. 3. Oxygen plasma etching reveals differences in strain as well as differences in aged and unaged morphology near and away from the burn hole. 4. Chlorosulfonic acid treated polyethylene can be thin sectioned to study void population by TEM.