Silicone Rubber Treatment with a Sodium Chloride Solution in the Presence of an Electric Field

High voltage silicone insulators that are placed close to coastal marine areas have the problem of salt fog depositing on their surfaces in the form of conductive droplets. Under the influence of an electric field, those droplets initiate partial discharges, which leads to the degradation of the hydrophobic properties of silicone rubber. This phenomenon, in which droplets serve as the cause of partial discharges, has been studied in considerable detail elsewhere. However, it remains unclear whether the droplets themselves, as moisture-laden areas, affect the properties of silicone rubber. The current work is focused on studying the combined effect of an AC electric field (E = 17 kV/cm) and a 4% solution of sodium chloride on the water-repellent properties of silicone rubber in the absence of electrical discharges. The results of the study show that the influence of moisture and an electric field leads to slowing down the droplet runoff from the inclined sample of Powersil 310 rubber. An AC electric field did not have a noticeable effect on the rate of water runoff; the slowdown was due to the pre-treatment of the sample with the solution.