COMPOSITION FOR HIGH VOLTAGE ELECTRICALLY INSULATING SILICONE RUBBER, HIGH VOLTAGE ELECTRICALLY INSULATING SILICONE RUBBER COMPOSITION AND HIGH VOLTAGE ELECTRICAL INSULATOR

摘要

PPROBLEM TO BE SOLVED: To provide a composition for a high voltage electrically insulating silicone rubber, a high voltage electrically insulating silicone rubber composition and a high voltage electrical insulator, excellent in tracking resistance. PSOLUTION: The composition for a high voltage electrically insulating silicone rubber comprises (A) 100 pts.wt. of an organopolysiloxane represented by the average unit formula: RSBa/SBSiOSB(4-a)/2/SB(wherein R denotes a monovalent unsubstituted hydrocarbon group or a halogenated hydrocarbon group; and (a) denotes 1.8-2.3) and having at least two silicon atom-coupling alkenyl groups per molecule, (B) 10-100 pts.wt. of dry-method silica hydrophobized with a cyclic dimethylsiloxane oligomer, (C) 10-400 pts.wt. of an aluminum hydroxide powder, and (D) 0-10 pts.wt. of a terminal silanol group-encapsulated diorganosiloxane oligomer or a silanol group-containing organosilane. The high voltage electrically insulating silicone rubber composition comprises the above composition for a high voltage electrically insulating silicone rubber and a curing agent (E) in an amount sufficient to cure the same. The high voltage electrical insulator is composed of a cured product of the high voltage electrically insulating silicone rubber composition. PCOPYRIGHT: (C)2006,JPO&NCIPI