Preparation and Corona Aging Studies on Nano alumina/Micro ATH Co-Filled HTV Silicone Rubber Composites

The study explores the behavior of nano alumina and micro ATH co-filled silicone composites under corona aging. Composites were developed through physical mixing with nano filler loadings levels varied from 0, 3, and 5 phr by weight. The procedure for surface treatment of fillers, and the fabrication method employed is described. Corona aging is achieved in the laboratory using a multipin electrode arrangement at 10 kV arcing voltage, for 50 hours. The effects of surface discharges are evaluated through measurement of static contact angle before and after corona aging. SEM analysis revealed the surface degradation patterns in the composites post corona aging. FTIR analysis is also performed to understand the structural changes that occur after corona aging. Tensile strength and percentage elongation at break is performed to analyze the effects of corona discharges on the bulk mechanical properties. Measurements of volume resistivity before and after corona aging points to the role of nano alumina in resisting the surface degradations. The effect of interface layer in resisting the deleterious effects of corona discharges is briefly discussed. Here, a method of preparation of micro and nano co-filled silicone rubber composites in high temperature vulcanizing rubber matrix is described, with experimental works.