Mechanical, Dielectric and Hydrophobic Properties of Phenyl Silicone Rubber and Methyl Vinyl Silicone Rubber Blend Composites

Silicone rubber (SIR) composite insulators are widely employed in electrical applications due to their exceptional chemical stability, low surface energy and superior electrical insulation properties. To enhance the hydrophobicity and low-temperature resistance of SIR, blended composites with varying ratios of SIR and phenyl silicone rubber (PSIR) were fabricated. The study revealed that matrix-filler network interactions between PSIR and fillers were weaker compared to those in SIR-based systems. Increasing PSIR content led to reduced elongation at break in the composites, while tensile strength remained largely unchanged. Concurrently, the breakdown strength is inferior to that of pure PSIR composites. Notably, the blend of SIR and PSIR enhances both hydrophobicity and resistance to hydrophobicity migration. This work provides a strategic approach for enhancing the performance of SIR composites suitable for applications in regions with high humidity and significant rainfall.