Study on improving the tracking and erosion resistance of silicone rubber

Metal hydroxide filler has an evident influence on the electrical properties of silicone rubber used for outdoor insulation. This paper investigates the influence of alumina trihydrate (ATH) and magnesium hydroxide on the tracking and erosion resistance of silicone rubber. The research shows that the insulation performance improves with increase of filler concentration of ATH and magnesium hydroxide, but that adding excessive filler depresses the performance again. The results show that the tracking and erosion resistance of compound hydroxide filler is superior to that of single hydroxide filler. The effect of hydroxide filler level on vulcanization characteristics of silicone rubber is also investigated. The filler decreases the vulcanization speed and the vulcanization degree, which affects the tracking and erosion resistance. The results can be explained by the presence of an active center in the silicone rubber.