| 摘要 |
1,212,663. Cellular polymers. UPJOHN CO. 14 Jan., 1969 [5 Feb., 1968], No. 2209/69. Headings C3C and C3R. Cellular polymers are prepared by bringing together, under foam producing conditions, (a) a polyisocyanate containing 35 to 85% by weight of methylenebis (phenyl isocyanate); (b) 0À01 to 0À25 equivalent per equivalent of the polyisocyanate of a tertiary amine; (c) 0 to 0À5 equivalent per equivalent of polyisocyanate of a homocyclic polyepoxide; and (d) 0 to 0À3 equivalent per equivalent of polyisocyanate of a polyol having an average functionality of 2 to 8 and an average equivalent weight of 30 to 1500, provided that when no polyol (d) is present the polyepoxide (c) is present in an amount from 0À0045 to 0À5 equivalent per equivalent of polyisocyanate and further provided that when no polyepoxide (c) is present the polyol (d) is present in an amount from 0À01 to 0À3 equivalent per equivalent of polyisocyanate, and wherein the total number of equivalents of polyepoxide (c) and polyol (d) do not exceed 0À6 equivalent per equivalent of polyisocyanate. Numerous examples are given of the components (a), (b), (c) and (d). In a typical example a quasi-prepolymer is prepared from a polyether polyol and modified methylenebis- (phenyl isocyanate) prepared by heating methylenebis(phenyl isocyanate) with triethylphosphate and mixed with a dimethyl polysiloxane polyethylene oxide block copolymer and trichlorofluoromethane to form a component A which is mixed with a component B comprising a mixture of an epoxy novolac resin and trichlorofluoromethane and a component C comprising a solution of 1,4-diazobicyclo[2.2.2]- octane in dipropylene glycol to form a foam. |
