High resiliency foam with improved load bearing ability by use of organotin mercaptides

Claim 1

A method for preparing a high resiliency polyurethane foam characterized by a value for the indentation load deflection, measured at 65% deflection, greater than one pound per square inch, said method comprising reacting at least one polyol selected from the group consisting of 1. polyols exhibiting a molecular weight of between 4,500 and 6,000 and a hydroxyl number from 25 to 45, 2. polyols exhibiting a molecular weight between 4,500 and 6,000 and a hydroxyl number from 25 to 45, wherein said polyol contains between 5 and 25%, based on the weight of said polyol, of side chains derived from the graft polymerization of acrylonitrile or a mixture of acrylonitrile and styrene, 3. mixtures of polyols exhibiting a molecular weight from 4,000 to 8,000 and a diamine as a cross-linking agent, said diamine being present in an amount from about 0.5 to 6%, based on the weight of said polyol, with a polyfunctional isocyanate, a blowing agent comprising water and from 0 to 10%, based on the weight of said blowing agent, of a volatile fluorinated hydrocarbon that boils from -40° to +70° C., a silicone-base surfactant and as the polymerization catalyst, from 0.001 to 0.1%, based on the weight of said polyol, of an organotin compound of the formula R 2 1 Sn(SR 2 COOR 3 ) wherein R 1 and R 3 are individually selected from the group consisting of alkyl radicals containing from 1 to 20 carbon atoms and R 2 is a methylene or ethylene radical.

Claim 2

A method for preparing a high resiliency polyurethane foam characterized by a value for the indentation load deflection, measured at 65% deflection, greater than one pound per square inch, said method comprising reacting at least one polyol selected from the group consisting of 1. polyols exhibiting a molecular weight of between 4,500 and 6,000 and a hydroxyl number from 25 to 45, 2. polyols exhibiting a molecular weight between 4,500 and 6,000 and a hydroxyl number from 25 to 45, wherein said polyol contains between 5 and 25%, based on the weight of said polyol, of side chains derived from the graft polymerization of acrylonitrile or a mixture of acrylonitrile and styrene, 3. mixtures of polyols exhibiting a molecular weight from 4,000 to 8,000 and a diamine as a cross-linking agent, said diamine being present in an amount from about 0.5 to 6%, based on the weight of said polyol, with a polyfunctional isocyanate, a blowing agent comprising water and from 0 to 10%, based on the weight of said blowing agent, of a volatile fluorinated hydrocarbon that boils from -40° to +70° C., a silicone-base surfactant and as the polymerization catalyst, from 0.001 to 0.1%, based on the weight of said polyol, of an organotin compound of the formula R 2 1 Sn(SR 2 COOR 3 ) wherein R 1 and R 3 are individually selected from the group consisting of alkyl radicals containing from 1 to 20 carbon atoms and R 2 is a methylene or ethylene radical.