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 catalyst: (a) 100 parts by weight of an organopolysiloxane gum represented by an average unit formula of RaSiO 4-a DIVIDED 2 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 <CHEM> wherein R<1> and R<2>, which may be the same or diferent, are each an unsubstituted or substituted monovalent hydrocarbon group, at least one of which is phenyl, 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. (