Effect of chemical corrosion on the anti-pollution flashover performance of methyl-silica superhydrophobic coatings

Methyl-silica superhydrophobic coatings have the capability of providing anti-pollution flashover protection for outdoor electrical insulators. However, in practical applications, the deposition and dissolution of atmospheric pollutants on the coating generates acidic or alkaline ions and leads to chemical degradation of the coating's surface property, which in turn causes a decrease in the anti-pollution flashover performance of the coating. Currently, there is a lack of research on the hydrophobic degradation characteristics of superhydrophobic methyl-silica coatings induced by chemical corrosion. Meanwhile, it is not clear how chemical corrosion affects the anti-pollution flashover performance of methyl-silica superhydrophobic coatings. To address the above issues, the static water contact angle and sliding angle on the corroded methyl-silica superhydrophobic coatings were tested to reflect the surface hydrophobicity degradation, and the results were theoretically interpreted; the surface leakage current amplitudes of the coatings aged to different degrees were measured under dirty and wet conditions to characterize the anti-pollution flashover performance of the corroded coatings. The surface leakage current amplitudes of the aged methyl-silica superhydrophobic coating under different corrosion environment temperatures, different applied electric field strengths, and different wetting times of surface pollutants are measured to characterize the anti-pollution flashover performance of the corrosion-aged coating, and the influences of the above factors on the anti-pollution flashover performance of the methyl-silica superhydrophobic coating are analyzed.