Recovery Behavior of Hydrophobicity of Silicone Rubber for Polymer Insulator Housing Deposited with Contaminant

This paper deals with recovery behavior of hydrophobicity of silicone rubber for polymer insulator housing after depositing artificial contaminant on its surface. Artificial contaminant was prepared based on TONOKO and sodium chloride. Recovery behavior of hydrophobicity of a specimen deposited with artificial contaminant was evaluated by receding contact angle and diameter of water droplets dropped on its surface. The specimen kept under high temperature and dry conditions recovered hydrophobicity faster than the specimen kept under low temperature and high humidity conditions. Also the specimen which contains much more amount of LMW (Low Molecular Weight) component recovered hydrophobicity faster than the specimen which contains less amount of LMW component. But adding low viscosity silicone oil to the silicone rubber lowered rubber properties, such as hardness, elongation, and tensile strength, and it was also clarified that an excess amount of low viscosity silicone oil made lowered tracking resistance performance of the specimen.