High dielectric insulating silicone rubber composition and electric field relaxation layer

摘要

Provided are a high dielectric insulating silicone rubber composition and an electric field relaxation layer. (A) An organopolysiloxane represented by the following formula (1): 100 parts by mass, R1nSiO (4-n) / 2 (1) (wherein R1 is the same or different and is an unsubstituted or substituted monovalent hydrocarbon group) (N) is a positive number of 1.95 to 2.04.) (B) Thermal black having an average primary particle diameter of 150 to 500 nm: 60 to 150 parts by mass, (C) Specific surface area by BET adsorption method Is a highly dielectric insulating silicone rubber composition containing 50 m 2 / g or more of reinforcing fumed silica: 5 to 100 parts by mass and (D) a curing agent: 0.1 to 10 parts by mass. A dielectric constant of 10 or more, a volume resistivity of 1.0 × 10 13 to 1.0 × 10 17 Ω · cm, a dielectric loss tangent of 0.1 or less, and a dielectric breakdown strength (BDV) of 7 kV / mm or more. A high dielectric insulating silicone rubber composition characterized by the following: