| 摘要 |
Pasty organopolysiloxane compositions are facilely injection-molded into elastomeric shaped articles at low pressures, at a temperature ranging from about 125 DEG C. to about 225 DEG C., and in a molding cycle of less than about 25 seconds, said pasty organopolysiloxane compositions comprising an intimate admixture of: (A1) 100 parts by weight of a diorganopolysiloxane oil having a viscosity of 500 to 300,000 mPa.s at 25 DEG C., consisting essentially of recurring units of the formula R2SiO and blocked at each end of the chain by units of the formula R2R'SiO0.5, in which formulae the symbols R, which are identical or different, represent hydrocarbon radicals which are unsubstituted or substituted by halogen atoms or cyano groups and which have 1 to 8 carbon atoms, and the symbol R' represents the same radicals as the symbols R and also a hydroxyl radical, an alkoxy radical having from 1 to 4 carbon atoms or a beta -methoxyethoxy radical; (B1) 10 to 75 parts by weight of a finely divided reinforcing silica having a specific surface area of at least 50 m2/g; (C1) 1 to 20 parts by weight of a structuring inhibitor; and (D1) 0.1 to 4 parts by weight of 2,4-dichlorobenzoyl peroxide cross-linking agent.
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