| 摘要 |
1,212,719. Halocarbon-inhibited platinumcatalysed composition. GENERAL ELECTRIC CO. 21 Feb., 1968 [30 March, 1967], No. 8424/68. Heading C3T. [Also in Division D1] An inhibited curable organopolysiloxane composition comprises (a) a polysiloxane of average general formula R a R<SP>1</SP> b SiO (4-a-b)/2 having at least two monovalent aliphatically unsaturated hydrocarbon radicals per molecule, (b) a polysiloxane of average general formula R a H b SiO (4-n-b)/2 having at least two Si-H groups per molecule, (c) a platinum compound catalyst and (d), as inhibitor a halocarbon having 2 carbon atoms and at least 3 F, Cl or Br atoms per molecule. Lists are given of suitable catalysts (c) and inhibitors (d). In examples a catalyst prepared from chloroplatinic acid and 2-ethylhexanol in benzene is added to mxtures of trimethylsilyl- or vinyldimethylsilyl-terminated polysiloxanes containing Me 2 SiO and ViMeSiO units, (a), and trimethylsilyl-terminated polysiloxanes containing Me 2 SiO and MeHSiO units, (b), with CCl 2 = CCl 2 , FCCl 2 CCl 2 F or CCl 2 = CHCl as inhibitors; the polysiloxane mixture is without solvent or is dissolved in benzene or excess inhibitor. Cloth is waterproofed with a solution of the latter type. In aerosol compositions the halocarbon may serve as inhibitor, solvent and propellant.
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