Corona Discharge Degradation and Dynamic Drop Tests for Hydrophobicity Evaluation of High-Temperature Vulcanizing Silicone Rubber Samples

In this paper, the hydrophobicity performance of acommercially available silicone-rubber samples was investigated by using the corona discharge-degradation test and dynamic drop test (DDT). The tests were carried out under AC, +DC, and −DC voltages. In the corona discharge-degradation test, corona discharge was applied to two samples under certain temperatures and humidity for 2 hours, and their hydrophobicity losses were examined using contact angle measurements. Then, the recovery of their hydrophobicity property was investigated. In the dynamic drop test, the loss of hydrophobicity with respect to time and the formation of a water path on the sample surface were observed. Five identical samples were utilized for the DDT.