SILICONE RUBBER COMPOSITION FOR HIGH VOLTAGE ELECTRICAL INSULATORS

摘要

A silicone rubber composition for high voltage electrical insulators capable of being converted to a rubbery elastomer superior in high voltage electrical insulating characteristics is provided. The composition comprises the following components (a) to (e) and not containing a platinum catalayst: (a) 100 parts by weight of an organopolysiloxane gum represented by an average unit formula of RaSiO wherein R is a monovalent hydrocarbon group, of which at least 50 mole% is alkyl, and a is a number of 1.98 to 2.02; (b) 10 - 100 parts by weight of a finely divided silica filler; (c) 15 - 300 parts by weight of aluminum hydroxide; (d) 1 - 20 parts by weight of an organosilane or organosiloxane oligomer represented by the general formula wherein R1 and R2, which may be the same or diferent, are each an unsubstituted or substituted monovalent hydrocarbon group, at least one of which is pehnyl, m is an integer of 1 to 20 and n is an integer of 0 to 20; and (e) 0.05 - 6 parts by weight of an organic peroxide.