CAOUTCHOUCS DE SILICONE AUTOCOLLANTS DURCISSABLES A

摘要

1349311 Isocyanurate-modified heat-curable silicone rubber compositions GENERAL ELECTRIC CO 14 March 1972 [8 April 1971] 11819/72 Heading C3T A self-bonding heat-curable silicone rubber composition comprises (a) an organopolysiloxane of viscosity at least 100,000 cP/25‹ C. and average unit formula R a SiO 4-a/2 wherein R is a hydrocarbonyl or halohydrocarbonyl radical and a is 1À95-2À01, (b) a curing catalyst, and (c) an isocyanurate wherein R1 is an unsaturated hydrocarbonyl or halohydrocarbonyl radical, R2 and R3 are as R or R1 and G is as R or R1 or is E 3-b R b 5SiR4-, where E is R6O- or R6COO-, R4 is a divalent hydrocarbon or halohydrocarbon radical, R5 and R6 are as R, and b is 0, 1, 2 or 3. There may also be present 10-100 wt. per cent of (a) of a filler and 1-25 wt. per cent of (a) of a process aid. In Examples 100 p.b.w. of a trimethylsiloxane-terminated polydimethylsiloxane containing 0À6 mol. per cent MeViSiO units is mixed with 15 or 20 p.b.w. of an alkoxy-terminated dimethylsiloxane-diphenylsiloxane copolymer as process aid and 60 or 40 p.b.w. of a pyrogenic silica filler; to these compositions is added 0À25 p.b.w. of t-butyl perbenzoate or dicumyl peroxide and 1-2 p.b.w. of triallyl, tri-octadecenyl, methyl divinyl, ethyl dibutenyl or trihexenyl isocyanurate, or trimethoxysilylpropyl diallyl isocyanurate.