GB1084233A - - Google Patents

Abstract

1,084,233. Siloxane-polyol compositions; polyurethane foams. UNION CARBIDE CORPORATION. Aug. 6, 1964 [Aug. 7, 1963], No. 31929/64. Headings C3C, C3R and C3T. Compositions comprise an organic polyol having more than 2 carbon-bonded hydroxyl radicals per polyol molecule and a copolymer of said polyol with an organosiloxane, the copolymer being intimately interspersed with the polyol. The organopolysiloxane groups form from 0À025-6 wt. per cent of the composition and are present as siloxane blocks containing 2 or more units represented by wherein a is 1, 2 or 3 and R is a monovalent hydrocarbon or halogen-substituted hydrocarbon group, or a divalent group bonded to the silicon by a C-Si linkage or a C-O-Si linkage, and if desired units of the formula wherein R is as defined above, e is 0, 1 or 2 and f is 1 or 2, and e+f is 1, 2 or 3. The compositions are produced by forming the copolymer in the presence of excess of the polyol by reaction of part of the polyol with from 0À026-6 wt. per cent based on the total wt. of the reaction mixture of an organopolysiloxane containing at least 2 groups per molecule that are reactive with the hydroxyl groups of the polyol. The reaction may be performed in the presence of a suitable catalyst and in modifications of the process (1) some of the hydroxyl groups of the polyol may be replaced by allyloxy groups when the siloxane contains silicon-bonded hydrogen, and (2) some of the hydroxyl groups of the polyol may be replaced by alkali metaloxy groups when the siloxane contains a halogen substituted hydrocarbyl group. Hydroxyl reactive groups specified are: alkoxy, aryloxy and acyloxy groups; hydrogen and halogen atoms; amino, hydroxyl, carboxyalkyl, epoxyalkoxyalkyl, vinyl, isocyanatoalkyl and -RO 2 C.NH.R.NCO groups bonded directly to silicon, where R is a divalent hydrocarbon radical. The compositions may be reacted with a polyisocyanate or polyisothiocyanate in the presence of a catalyst and a blowing agent by any of the usual techniques to give foams. The preferred polyols are the polyoxyalkylene polyols. A chloromethylated organopolysiloxane is prepared in an example by reacting a trimethylsilyl terminated dimethylsiloxane/2-phenylisopropylmethylsiloxane copolymer with chloromethyl methyl ether in the presence of ZnCl 2 to give a copolymer containing 2-(chloromethylphenyl)isopropylmethylsiloxane groups. A partial sodium salt of a polyoxypropylated glycerol is prepared in an example by reacting the polyol with sodium dispersed in toluene. A partial allyl ether of polyoxypropylated glycerol is prepared by reacting the partial sodium salt with allyl bromide.