Development and evaluation of a new product line of silicone elastomers for high voltage applications. Part 2

Silicone elastomers used for high voltage applications have proven their necessity in the areas of insulators, arresters, and cable accessories. There are many factors that make silicone materials advantageous in the insulator industry. These advantages include: long term endurance, hydrophobic recovery, and easy processing. We report on the latest results of ongoing accelerated aging studies being performed on a new line of silicone elastomers designed specifically for high voltage insulation applications. Earlier this year (ISEI 2000, 3Apr00), we presented the first of a multi part study designed to investigate the performance changes of high voltage insulation (HVI) materials exposed to energized salt fog and to ultraviolet radiation and condensation. Surface electrical activity under salt fog aging is continuously monitored by a data acquisition system. Effects of the accelerated aging on the loss and recovery of hydrophobicity of the silicone elastomers are monitored by dynamic water contact angle, while SEM and XPS are used to characterize surface structural effects as a result of aging. Bulk physical and electrical properties are also reported.