Patent ID: 6124369
Filing Date: 2000-09-26
Classification: C08G

Abstract:
A process for producing a polyurethane foam by blowing and curing a polyurethane foam composition comprising a polyol, water, a catalyst, a surfactant and a polyisocyanate;said process comprising the step of mixing a resin premix comprising the polyol, the water, the catalyst and the surfactant, with the polyisocyanate to cause the composition to foam and cure;said resin premix containing an organosilicon resin having as structural units an R.sup.1.sub.3 SiO.sub.1/2 unit wherein the R.sup.1 's are the same or different and each represents a monovalent hydrocarbon group having 1 to 6 carbon atoms, an R.sup.2 SiO.sub.3/2 unit wherin R.sup.2 represents a monovalent hydrocarbon group having 1 to 20 carbon atoms, and an SiO.sub.4/2 unit;wherein said organosilicon resin is produced by a process comprising the steps of:subjecting a mixture of a compound selected from the group consisting of a silane compound represented by the general formula (I):Si(OR.sup.3).sub.4 (I)wherein the R.sup.3 's are the same or different and each represents a monovalent hydrocarbon group having 1 to 6 carbon atoms, and a hydrolysis-condensation product thereof;a compound selected from the group consisting of a silane compound represented by the general formula (II):R.sup.2 Si(OR.sup.4).sub.3 (II)wherein R.sup.2 represents a monovalent hydrocarbon group having 1 to 20 carbon atoms, and the R.sup.4 's are the same or different end each represents a monovalent hydrocarbon group having 1 to 6 carbon atoms, and a hydrolysis-condensation product thereof; anda silane compound represented by the general formula (III):R.sup.1.sub.3 SiX (III)wherein X represents an --OH group, an --OSiR.sup.1.sub.3 group or a hydrolyzable group, and the R.sup.1 's are the same or different and each represent a monovalent hydrocarbon group having 1 to 6 carbon atoms;to equilibration reaction with an acid;adding water to the product of the equilibration reaction to carry out hydrolysis reaction; andadding an aqueous alkali to the product of the hydrolysis reaction to carry out condensation reaction.