The effect of ATH and silica on tracking and erosion resistance of silicone rubber compounds for outdoor insulation

In this work, the influence of particle size and concentration of fillers used in silicone rubber compounds for outdoor insulation is investigated. Alumina tri-hydrate and silica with mean particle sizes of 5 and 10 /spl mu/m are used as fillers with concentrations of 10, 30 and 50% by weight in a two-part room temperature vulcanized silicone rubber base polymer. The results from inclined plane tests show that samples with high concentrations of filler and/or smaller particle size have better tracking and erosion resistance than samples with lower concentration and/or larger particle size.