Room temperature curable polyorganosiloxane composition and method

Claim 2

A room temperature curing polyorganosiloxane composition comprising: (A) 100 parts by weight of a silanol-terminated polydiorganosiloxane having a viscosity of 500 to 200,000 centistokes at 25° C., (B) 0.5-25 parts by weight of an oxime radical-methoxyl radical exchange reaction product obtained from: (1) an oxime radical-containing organosilicon compound selected from the group consisting of oxime radical-containing silanes of the general formula: R.sub.a.sup.1 Si(ON═Q).sub.4-a wherein R 1 represents a substituted or unsubstituted monovalent hydrocarbon radical, ═Q represents a bivalent radical of the formula: ##STR10## R 2 and R 3 respectively represent a monovalent radical selected from the group consisting of hydrogen atoms and substituted or unsubstituted monovalent hydrocarbon radicals, R 4 represents an alkylene radical of 4 to 6 carbon atoms, and a represents a number of 0 or 1 and partially hydrolyzed condensates thereof, and (2) a methoxyl radical-containing organosilicon compound selected from the group consisting of methoxyl radical-containing silanes of the general formula: R.sub.b.sup.5 Si(OCH.sub.3).sub.4-b wherein R 5 represents a substituted or unsubstituted monovalent hydrocarbon radical, and b represents a number of 0 or 1 and partially hydrolyzed condensates thereof, in such amounts that a molar ratio of the oxime radical bonded with the silicon atom will be 1:(0.2-2.0); and (C) 0.01 to 10 parts by weight of a catalyst for promoting the reaction of (A) and (B).

Claim 3

A composition according to claim 1 which further contains an inorganic filler.

Claim 4

A composition according to claim 1 wherein the organic radical bonded with silicon atom in (A) is a monovalent hydrocarbon radial selected from the group consisting of methyl, vinyl and phenyl radicals.

Claim 5

A composition according to claim 3 wherein at least 85% of the organic radicals bonded with the silicon atom in (A) are methyl radicals.

Claim 6

A composition according to claim 3 wherein the organic radical bonded with the silicon atom in (A) is a methyl radical.

Claim 7

A composition according to claim 1 wherein R 1 is a monovalent hydrocarbon radical selected from the group consisting of alkyl radicals of 1 to 8 carbon atoms, alkenyl radicals of 2 to 3 carbon atoms and phenyl radicals.

Claim 8

A composition according to claim 6 wherein R 1 is a methyl radical.

Claim 9

A composition according to claim 1 wherein ═Q represents ##STR11## R 2 and R 3 respectively represent an alkyl radical of 1 to 2 carbon atoms which may be the same as or different from each other.

Claim 10

A composition according to claim 1 wherein R 5 is a monovalent hydrocarbon radical selected from the group consisting of alkyl radicals of 1 to 8 carbon atoms, alkenyl radicals of 2 to 3 carbon atoms and phenyl radicals.

Claim 11

A composition according to claim 1 wherein (B) is a reaction product of (1) and (2) obtained upon heating.

Claim 12

A process for producing a room temperature curing polyorganosiloxane composition comprising the steps of combining: (A) 100 parts by weight of a silanol-terminated polydiorganosiloxane having a viscosity of 500-200,000 centistokes at 25° C., with (B) 0.5-25 parts by weight of an oxime radical-methoxyl radical exchange reaction product obtained by reacting: (1) an oxime radical-containing organosilicon compound selected from the group consisting of oxime radical-containing silanes of the general formula: R.sub.a.sup.1 Si(ON═Q).sub.4-a wherein R 1 represents a substituted or unsubstituted monovalent hydrocarbon radical, ═Q represents a bivalent radical of the formula: ##STR12## R 2 and R 3 respectively represent a monovalent radical selected from the group consisting of hydrogen atoms and substituted or unsubstituted monovalent hydrocarbon radicals, R 4 represents an alkylene radical of 4 to 6 carbon atoms, and a represents a number of 0 or 1 and partially hydrolyzed condensates thereof, and (2) a methoxyl radical-containing organosilicon compound selected from the group consisting of methoxyl radical-containing silanes of the general formula: R.sub.b.sup.5 Si(OCH.sub.3).sub.4-b wherein R 5 represents a substituted or unsubstituted monovalent hydrocarbon radical, and b represents a number of 0 to 1 and partially hydrolyzed condensates thereof, in such amounts that a molar ratio of the oxime radical bonded with the silicon atom will be 1:(0.2-2.0); and (C) 0.01 to 10 parts by weight of a catalyst for promoting the reaction of (A) and (B).

Claim 13

A process for producing a room temperature curing polyorganosiloxane composition comprising the steps of combining: (A) 100 parts by weight of a silanol-terminated polydiorganosiloxane having a viscosity of 500-200,000 centistokes at 25° C., with (B) 0.5-25 parts by weight of an oxime radical-methoxyl radical exchange reaction product obtained by reacting: (1) an oxime radical-containing organosilicon compound selected from the group consisting of oxime radical-containing silanes of the general formula: R.sub.a.sup.1 Si(ON═Q).sub.4-a wherein R 1 represents a substituted or unsubstituted monovalent hydrocarbon radical, ═Q represents a bivalent radical of the formula: ##STR12## R 2 and R 3 respectively represent a monovalent radical selected from the group consisting of hydrogen atoms and substituted or unsubstituted monovalent hydrocarbon radicals, R 4 represents an alkylene radical of 4 to 6 carbon atoms, and a represents a number of 0 or 1 and partially hydrolyzed condensates thereof, and (2) a methoxyl radical-containing organosilicon compound selected from the group consisting of methoxyl radical-containing silanes of the general formula: R.sub.b.sup.5 Si(OCH.sub.3).sub.4-b wherein R 5 represents a substituted or unsubstituted monovalent hydrocarbon radical, and b represents a number of 0 to 1 and partially hydrolyzed condensates thereof, in such amounts that a molar ratio of the oxime radical bonded with the silicon atom will be 1:(0.2-2.0); and (C) 0.01 to 10 parts by weight of a catalyst for promoting the reaction of (A) and (B).

Claim 14

A process as in claim 11 further comprising the step of adding an inorganic filler to said composition.

Claim 15

A process according to claim 11 wherein the organic radical bonded with silicon atom in (A) is a monovalent hydrocarbon radical selected from the group consisting of methyl, vinyl and phenyl radicals.

Claim 16

A process according to claim 13 wherein at least 85% of the organic radicals bonded with the silicon atoms in (A) are methyl radicals.

Claim 17

A process according to claim 13 wherein the organic radical bonded with the silicon atom in (A) is a methyl radical.

Claim 18

A process according to claim 11 wherein R 1 is a monovalent hydrocarbon radical selected from the group consisting of alkyl radicals of 1 to 8 carbon atoms, alkenyl radicals of 2 to 3 carbon atoms and phenyl radicals.

Claim 19

A process according to claim 16 wherein R 1 is a methyl radical.

Claim 20

A process according to claim 11 wherein ═Q represents ##STR13## R 2 and R 3 respectively represent an alkyl radical of 1 to 2 carbon atoms which may be the same as or different from each other.

Claim 21

A process according to claim 11 wherein R 5 is a monovalent hydrocarbon radical selected from the group consisting of alkyl radicals of 1 to 8 carbon atoms, alkenyl radicals of 2 to 3 carbon atoms and phenyl radicals.

Claim 22

A process according to claim 11 wherein (B) is a reaction product of (1) and (2) obtained upon heating.

Claim 23

A process according to claim 11 further comprising the step of extruding said polyorganosiloxane composition.

Claim 24

A process according to claim 11 or 21 further comprising the step of curing said polyorganosiloxane composition upon exposure to moisture in air.