abstract |
A silicone rubber composition for extrusion molding applications having a high cure rate and providing silicone rubber extrusion moldings that post-cure and are either free of bubbles or contain bubbles to limited extent. The silicone rubber composition includes (A) 100 weight parts of a silicone rubber base compound containing (a-1) a diorganopolysiloxane gum, (a-2) reinforcing silica, and (a-3)a silanol-endblocked organosiloxane oligomer or hexaorganodisilazane; and (B) 0.1 to 10 weight parts of an organoperoxide with the formula R—COOOCOO—R 1 —OOCOOOC—R where R is an alkyl group, an alkoxy group, the group —SiR 2 3 , the group —CH 2 SiR 2 3 , or the group -Ph-R 3 c where R 2 is an alkyl or alkoxy group, Ph is phenyl when c is 0, and phenylene when c is 1, 2 or 3, R 3 is an alkyl group, an alkoxy group, the group —SiR 2 3 , or the group —CH 2 SiR 2 3 ; c is 0 to 3, and R 1 is a C 1 to C 10 alkylene group. |