Method of preparing heat cured siloxane foams using rhodium catalyst and foams prepared therefrom

Claim 1

A method of preparing a heat cured organosiloxane foam comprising mixing an organohydrogensiloxane having an average of at least three silicon-bonded hydrogen atoms per molecule, an average of no more than one silicon-bonded hydrogen atom per silicon atom and organic radicals selected from the group consisting of alkyl radicals having from one to six carbon atoms per radical, phenyl and 3,3,3-trifluoropropyl, a hydroxylated organosiloxane having an average of from greater than 1.0 to 2.5 silicon-bonded hydroxyl radicals per molecule and having an average of at least one organic radical per silicon atom selected from the group consisting of alkyl radicals having from one to six carbon atoms per radical, phenyl and 3,3,3-trifluoropropyl and a rhodium catalyst selected from a rhodium complex of a formula selected from the group consisting of: RhCl 3 S(CH 2 CH 3 ){CH 2 Si(CH 3 ) 3 } 3 , RhCl 3 S(CH 2 CH 2 CH 2 CH 3 ){CH 2 Si(CH 3 ) 3 } 3 , RhCl{(CH 3 CH 2 ) 2 S} 3 , RhCl 3 {(CH 3 CH 2 CH 2 CH 2 ) 2 S} 3 , Rh 2 Cl 6 P(CH 3 ){CH 2 Si(CH 3 ) 3 } 2 3 , Rh 2 Cl 6 P(CH 3 ){CH 2 Si(CH 3 ) 3 } 2 4 , RhCl 3 P(C 6 H 5 ) 2 {CH 2 Si(CH 3 ) 3 } 3 , RhCl(CO) P(CH 3 ){CH 2 Si(CH 3 ) 3 } 2 2 and RhCl(CO){P(C 6 H 5 ) 3 } 2 , said rhodium catalyst being present in an amount of at least 0.0025 grams per 100 grams of the hydroxylated organosiloxane, said organohydrogensiloxane and said hydroxylated organosiloxane being present in sufficient amounts to provide a molar ratio of silicon-bonded hydrogen atoms to silicon-bonded hydroxyl radicals of 2.5 to 40, where a mixture is obtained having a viscosity of less than 100,000 cps. at 25° C. and a pot life of at least 8 hours, thereafter heating said mixture above 90° C. to form a foam.

Claim 2

A method of preparing a heat cured organosiloxane foam comprising mixing an organohydrogensiloxane having an average of at least three silicon-bonded hydrogen atoms per molecule, an average of no more than one silicon-bonded hydrogen atom per silicon atom and organic radicals selected from the group consisting of alkyl radicals having from one to six carbon atoms per radical, phenyl and 3,3,3-trifluoropropyl, a hydroxylated organosiloxane having an average of from greater than 1.0 to 2.5 silicon-bonded hydroxyl radicals per molecule and having an average of at least one organic radical per silicon atom selected from the group consisting of alkyl radicals having from one to six carbon atoms per radical, phenyl and 3,3,3-trifluoropropyl and a rhodium catalyst selected from a rhodium complex of a formula selected from the group consisting of: RhCl 3 S(CH 2 CH 3 ){CH 2 Si(CH 3 ) 3 } 3 , RhCl 3 S(CH 2 CH 2 CH 2 CH 3 ){CH 2 Si(CH 3 ) 3 } 3 , RhCl{(CH 3 CH 2 ) 2 S} 3 , RhCl 3 {(CH 3 CH 2 CH 2 CH 2 ) 2 S} 3 , Rh 2 Cl 6 P(CH 3 ){CH 2 Si(CH 3 ) 3 } 2 3 , Rh 2 Cl 6 P(CH 3 ){CH 2 Si(CH 3 ) 3 } 2 4 , RhCl 3 P(C 6 H 5 ) 2 {CH 2 Si(CH 3 ) 3 } 3 , RhCl(CO) P(CH 3 ){CH 2 Si(CH 3 ) 3 } 2 2 and RhCl(CO){P(C 6 H 5 ) 3 } 2 , said rhodium catalyst being present in an amount of at least 0.0025 grams per 100 grams of the hydroxylated organosiloxane, said organohydrogensiloxane and said hydroxylated organosiloxane being present in sufficient amounts to provide a molar ratio of silicon-bonded hydrogen atoms to silicon-bonded hydroxyl radicals of 2.5 to 40, where a mixture is obtained having a viscosity of less than 100,000 cps. at 25° C. and a pot life of at least 8 hours, thereafter heating said mixture above 90° C. to form a foam.

Claim 8

A method of preparing a heat cured organosiloxane foam comprising mixing an organohydrogensiloxane having an average of at least three silicon-bonded hydrogen atoms per molecule, an average of no more than one silicon-bonded hydrogen atom per silicon atom and organic radicals selected from the group consisting of alkyl radicals having from one to six carbon atoms per radical, phenyl and 3,3,3-trifluoropropyl, a hydroxylated organosiloxane having an average of from 1.5 to 2.5 silicon-bonded hydroxyl radicals per molecule and having an average of at least one organic radical per silicon atom selected from the group consisting of alkyl radicals having from one to six carbon atoms per radical, phenyl and 3,3,3-trifluoropropyl, a benzene-soluble vinyl containing triorganosiloxy endblocked polydiorganosiloxane having an average of about two vinyl radicals per molecule and present in an amount equal to no more than 85 weight percent of the combined weight of the hydroxylated organosiloxane and the benzene-soluble vinyl containing triorganosiloxy endblocked polydiorganosiloxane, the organic radicals of the benzene-soluble vinyl containing triorganosiloxy endblocked polydiorganosiloxane being selected from the group consisting of alkyl radicals having from one to six carbon atoms per radical, phenyl, vinyl and 3,3,3-trifluoropropyl and a rhodium catalyst selected from a rhodium complex of a formula selected from the group consisting of RhCl 3 S(CH 2 CH 3 ){CH 2 Si(CH 3 ) 3 } 3 , RhCl 3 S(CH 2 CH 2 CH 2 CH 3 ){CH 2 Si(CH 3 ) 3 } 3 , RhCl 3 {(CH 3 CH 2 ) 2 S} 3 , RhCl 3 {(CH 3 CH 2 CH 2 CH 2 ) 2 S} 3 , Rh 2 Cl 6 P(CH 3 ){CH 2 Si(CH 3 ) 3 } 2 3 , Rh 2 Cl 6 P(CH 3 ){CH 2 Si(CH 3 ) 3 } 2 4 , RhCl 3 P(C 6 H 5 ) 2 {CH 2 Si(CH 3 ) 3 } 3 , RhCl(CO) P(CH 3 ){CH 2 Si(CH 3 ) 3 } 2 2 and RhCl(CO){P(C 6 H 5 ) 3 } 2 , said rhodium catalyst being present in an amount of at least 0.0025 grams per 100 grams of the hydroxylated organosiloxane, said organohydrogensiloxane and said hydroxylated organosiloxane being present in sufficient amounts to provide a molar ratio of silicon-bonded hydrogen atoms to silicon-bonded hydroxyl radicals of 0.5 to 40, where a mixture is obtained having a viscosity of less than 100,000 cps. at 25° C. and a pot life of at least 8 hours, thereafter heating said mixture above 90° C. to form a foam.

Claim 9

A method of preparing a heat cured organosiloxane foam comprising mixing an organohydrogensiloxane having an average of at least three silicon-bonded hydrogen atoms per molecule, an average of no more than one silicon-bonded hydrogen atom per silicon atom and organic radicals selected from the group consisting of alkyl radicals having from one to six carbon atoms per radical, phenyl and 3,3,3-trifluoropropyl, a hydroxylated organosiloxane having an average of from 1.5 to 2.5 silicon-bonded hydroxyl radicals per molecule and having an average of at least one organic radical per silicon atom selected from the group consisting of alkyl radicals having from one to six carbon atoms per radical, phenyl and 3,3,3-trifluoropropyl, a benzene-soluble vinyl containing triorganosiloxy endblocked polydiorganosiloxane having an average of about two vinyl radicals per molecule and present in an amount equal to no more than 85 weight percent of the combined weight of the hydroxylated organosiloxane and the benzene-soluble vinyl containing triorganosiloxy endblocked polydiorganosiloxane, the organic radicals of the benzene-soluble vinyl containing triorganosiloxy endblocked polydiorganosiloxane being selected from the group consisting of alkyl radicals having from one to six carbon atoms per radical, phenyl, vinyl and 3,3,3-trifluoropropyl and a rhodium catalyst selected from a rhodium complex of a formula selected from the group consisting of RhCl 3 S(CH 2 CH 3 ){CH 2 Si(CH 3 ) 3 } 3 , RhCl 3 S(CH 2 CH 2 CH 2 CH 3 ){CH 2 Si(CH 3 ) 3 } 3 , RhCl 3 {(CH 3 CH 2 ) 2 S} 3 , RhCl 3 {(CH 3 CH 2 CH 2 CH 2 ) 2 S} 3 , Rh 2 Cl 6 P(CH 3 ){CH 2 Si(CH 3 ) 3 } 2 3 , Rh 2 Cl 6 P(CH 3 ){CH 2 Si(CH 3 ) 3 } 2 4 , RhCl 3 P(C 6 H 5 ) 2 {CH 2 Si(CH 3 ) 3 } 3 , RhCl(CO) P(CH 3 ){CH 2 Si(CH 3 ) 3 } 2 2 and RhCl(CO){P(C 6 H 5 ) 3 } 2 , said rhodium catalyst being present in an amount of at least 0.0025 grams per 100 grams of the hydroxylated organosiloxane, said organohydrogensiloxane and said hydroxylated organosiloxane being present in sufficient amounts to provide a molar ratio of silicon-bonded hydrogen atoms to silicon-bonded hydroxyl radicals of 0.5 to 40, where a mixture is obtained having a viscosity of less than 100,000 cps. at 25° C. and a pot life of at least 8 hours, thereafter heating said mixture above 90° C. to form a foam.