Solvent resistant vulcanizable silicone rubber compositions made with fluorosilicone hydride cross linking agents

Claim 2

A solvent resistant vulcanizable silicone rubber composition comprising: (A) 100 parts of a mixture comprised of: (i) 100 parts of a vinyl-containing polymer of the formula, ##STR11## where Vi is vinyl, R is selected from the group consisting of alkyl radicals of 1 to about 8 carbon atoms and phenyl, R' is perfluoroalkyl of 1 to about 8 carbon atoms, x is at least 1, and y is at least 10, and the viscosity of the compound is at least 300 centipoise at 25° C., and the concentration of siloxy units taken y times varies from about 5 to about 98 mole percent; (ii) from about 10 to about 60 parts of a resin having SiO 2 units; a siloxane having a perfluorinated alkyl selected from the group consisting of R" SiO 1 .5 units, RR"SiO units, R 2 R"SiO 0 .5 units and mixtures thereof; and vinyl-containing siloxane units selected from the group consisting of ViRR"SiO 0 .5, ViR 2 SiO 0 .5, ViR"SiO, ViRSiO and mixtures thereof; where the hydrocarbon substituent to Si ratio varies from about 0.8 to about 2.4; Vi is vinyl; R is selected from the group consisting of alkyl radicals of 1 to about 8 carbon atoms and phenyl; R" is a (--CH 2 --) a R' radical where R' is perfluoroalkyl of 1 to about 8 carbon atoms, a is at least 2 but less than 10 and (--CH 2 --) a is straight or branched chain; (iii) a suitable amount of catalyst capable of promoting the cure of the mixture; and (B) from about 1 to about 50 parts, based on 100 parts of the mixture (A), of a crosslinking polymer having about 0.75 to about 3.0 moles of R 2 HSiO 0 .5, about 0.37 to about 1.5 moles of R"SiO 1 .5, and about 0.5 to about 1.5 moles of SiO 2 , wherein R is selected from the group consisting of alkyl radicals of 1 to about 8 carbon atoms and phenyl; and R" is a (--CH 2 --) a R' radical where R' is perfluoroalkyl of 1 to about 8 carbon atoms, a is at least 2 but less than 10, and (--CH 2 --) a is straight or branched chain.

Claim 3

The solvent resistant vulcanizable silicone rubber composition of claim 1 further comprising up to about 100 parts of a filler.

Claim 4

The solvent resistant vulcanizable silicone rubber composition of claim 2 wherein the filler is selected from the group consisting of titanium dioxide, lithopone, zinc oxide, zirconium silicate, silica aerogel, iron oxide, diatomaceous earth, calcium carbonate, fumed silica, precipitated silica, glass fibers, magnesium oxide, chromic oxide, zirconium oxide, aluminum oxide, alpha quartz, calcined clay, asbestos, carbon, graphite, cork, cotton and synthetic fibers.

Claim 5

The solvent resistant vulcanizable silicone rubber composition of claim 3 wherein the filler has been treated with a silicon compound.

Claim 6

The solvent resistant vulcanizable silicone rubber composition of claim 4 wherein the silicon compound is a silazane.

Claim 7

The solvent resistant vulcanizable silicone rubber composition of claim 1 wherein the viscosity of vinyl-containing (i) is about 1,000 to about 200,000 centipoise at 25° C.

Claim 8

The solvent resistant vulcanizable silicone rubber composition of claim 1 wherein the catalyst is platinum or a platinum compound.

Claim 9

The solvent resistant vulcanizable silicone rubber composition of claim 7 wherein the platinum catalyst is platinum complexed with a vinyl-containing polysiloxane.

Claim 10

The solvent resistant vulcanizable silicone rubber composition of claims 1, 7 or 8 wherein the catalyst comprises about 0.1 to about 50 parts per million of the total composition.

Claim 11

The solvent resistant vulcanizable silicone rubber composition of claims 1 or 2 wherein the R' of component (ii) is --CF 3 , and a is 2.

Claim 12

The solvent resistant vulcanizable silicone rubber composition of claims 1 or 2 wherein R is --CH 3 , and R" is --CH 2 CH 2 CF 3 .

Claim 13

The solvent resistant vulcanizable silicone rubber composition of claims 1 or 2 wherein the R"SiO 1 .5 units of component (ii) are derived from trifluoropropyltrichlorosilane; the RR"SiO units of component (ii) are derived from (methyl)trifluoropropyldichlorosilane; and the R 2 R"SiO 0 .5 units of component (ii) are derived from (dimethyl)trifluoropropylmonochlorosilane.

Claim 14

The solvent resistant vulcanizable silicone rubber composition of claim 1 wherein in the crosslinking polymer, R 2 HSiO 0 .5 is about 1.5 moles, R"SiO 1 .5 is about 0.75 mole, and SiO 2 is about 1.0 mole.

Claim 15

The solvent resistant vulcanizable silicone rubber composition of claims 1 or 13 wherein the crosslinking polymer is ##STR12## where s and t are about 10 to about 2,000, and the amount of (CH 3 ) 2 HSi-- is equal to or greater than t, and the viscosity is about 30 centipoise to about 4,000 centipoise at 25° C.

Claim 16

The solvent resistant vulcanizable silicone rubber composition of claims 1 or 13 wherein in the crosslinking polymer, R 2 HSiO 0 .5 is derived from dimethylhydrochlorosilane; R"SiO 1 .5 is derived from trifluoropropyltrichlorosilane; and SiO 2 is derived from ethyl silicate.

Claim 17

The solvent resistant vulcanizable silicone rubber composition of claims 1 or 13 wherein the crosslinking polymer is ##STR13## where R and R' are defined in claim 1; s and t are at least 10; and x and z are zero, a positive integer or a combination thereof, and x+z is greater than t to provide a liquid polymer.

Claim 18

A process for making solvent resistant silicone elastomers comprising: (a) mixing: (A) 100 parts of a mixture comprised of: (i) 100 parts of vinyl-containing polymer of the formula, ##STR14## wherein Vi is vinyl, R is selected from the group consisting of alkyl radicals of 1 to about 8 carbon atoms and phenyl, R' is perfluoroalkyl of 1 to about 8 carbon atoms, x is at least 1, and y is at least 10, and the viscosity of the compound is at least 300 centipoise at 25° C., and the concentration of siloxy units taken y times varies from about 5 to about 98 mole percent; (ii) from about 1.0 to about 60 parts of a resin having SiO 2 units; a siloxane having a perfluorinated alkyl selected from the group consisting of R"SiO 1 .5 units, RR"SiO units, R 2 R"SiO 0 .5 units and mixtures thereof; and vinyl-containing siloxane units selected from the group consisting of ViRR"SiO 0 .5, ViR 2 SiO 0 .5, ViR"SiO, ViRSiO and mixtures thereof; where the hydrocarbon substituent to Si ratio varies from about 0.8 to about 2.4; Vi is vinyl; R is selected from the group consisting of alkyl radicals of 1 to about 8 carbon atoms and phenyl; R" is a (--CH 2 --) a R' radical where R' is perfluoroalkyl of 1 to about 8 carbon atoms, a is at least 2 but less than 10 and (--CH 2 --) a is a straight or branched chain; and (iii) a suitable amount of catalyst capable of promoting the cure of the mixture; with (B) from about 1 to about 50 parts, based on 100 parts of the mixture (A), of a crosslinking polymer having about 0.75 to about 3.0 moles of R 2 HSiO 0 .5, about 0.37 to about 1.5 moles of R"SiO 1 .5, and about 0.5 to about 1.5, moles of SiO 2 , wherein R is selected from the group consisting of alkyl radicals of 1 to about 8 carbon atoms and phenyl; and R" is a (--CH 2 --) a R' radical where R' is perfluoroalkyl of 1 to about 8 carbon atoms, a is at least 2 but less than 10, and (--CH 2 --) a is straight or branched chain; and (b) allowing the mixture to cure.

Claim 19

A process for making solvent resistant silicone elastomers comprising: (a) mixing: (A) 100 parts of a mixture comprised of: (i) 100 parts of vinyl-containing polymer of the formula, ##STR14## wherein Vi is vinyl, R is selected from the group consisting of alkyl radicals of 1 to about 8 carbon atoms and phenyl, R' is perfluoroalkyl of 1 to about 8 carbon atoms, x is at least 1, and y is at least 10, and the viscosity of the compound is at least 300 centipoise at 25° C., and the concentration of siloxy units taken y times varies from about 5 to about 98 mole percent; (ii) from about 1.0 to about 60 parts of a resin having SiO 2 units; a siloxane having a perfluorinated alkyl selected from the group consisting of R"SiO 1 .5 units, RR"SiO units, R 2 R"SiO 0 .5 units and mixtures thereof; and vinyl-containing siloxane units selected from the group consisting of ViRR"SiO 0 .5, ViR 2 SiO 0 .5, ViR"SiO, ViRSiO and mixtures thereof; where the hydrocarbon substituent to Si ratio varies from about 0.8 to about 2.4; Vi is vinyl; R is selected from the group consisting of alkyl radicals of 1 to about 8 carbon atoms and phenyl; R" is a (--CH 2 --) a R' radical where R' is perfluoroalkyl of 1 to about 8 carbon atoms, a is at least 2 but less than 10 and (--CH 2 --) a is a straight or branched chain; and (iii) a suitable amount of catalyst capable of promoting the cure of the mixture; with (B) from about 1 to about 50 parts, based on 100 parts of the mixture (A), of a crosslinking polymer having about 0.75 to about 3.0 moles of R 2 HSiO 0 .5, about 0.37 to about 1.5 moles of R"SiO 1 .5, and about 0.5 to about 1.5, moles of SiO 2 , wherein R is selected from the group consisting of alkyl radicals of 1 to about 8 carbon atoms and phenyl; and R" is a (--CH 2 --) a R' radical where R' is perfluoroalkyl of 1 to about 8 carbon atoms, a is at least 2 but less than 10, and (--CH 2 --) a is straight or branched chain; and (b) allowing the mixture to cure.

Claim 20

The process of claim 17 further comprising adding up to about 100 parts of a filler to mixture (A).

Claim 21

The process of claim 18 wherein the filler is selected from the group consisting of titanium dioxide, lithopone, zinc oxide, zirconium silicate, silica aerogel, iron oxide, diatomaceous earth, calcium carbonate, fumed silica, precipitated silica, glass fibers, magnesium oxide, chromic oxide, zirconium oxide, aluminum oxide, alpha quartz, calcined clay, asbestos, carbon, graphite, cork, cotton and synthetic fibers.

Claim 22

The process of claim 19 wherein the filler has been treated with a silicon compound.

Claim 23

The process of claim 20 wherein the silicon compound is a silazane.

Claim 24

The process of claim 17 wherein the viscosity of vinyl-containing (i) is about 1,000 to about 200,000 centipoise at 25° C.

Claim 25

The process of claim 17 wherein the catalyst is platinum or a platinum compound.

Claim 26

The process of claim 23 wherein the platinum catalyst is platinum complexed with a vinyl-containing polysiloxane.

Claim 27

The process of claims 17, 23 or 24 wherein the catalyst comprises about 0.1 to about 50 parts per million of the total composition.

Claim 28

The process of claims 17 or 18 wherein the R' of component (ii) is --CF 3 , and a is 2.

Claim 29

The process of claims 17 or 18 wherein R is --CH 3 , and R" is --CH 2 CH 2 CF 3 .

Claim 30

The process of claims 17 or 18 wherein the R"SiO 1 .5 units of component (ii) are derived from trifluoroproplytrichlorosilane; the RR"SiO units of component (ii) are derived from (methyl)trifluoropropyldichlorosilane; and the R 2 R"SiO 0 .5 units of component (ii) are derived from (dimethyl)trifluoropropylmonochlorosilane.

Claim 31

The process of claims 17 or 18 wherein the SiO 2 units of the components are derived from ethyl silicate.

Claim 32

The process of claims 17 or 18 further comprising adding up to about 10,000 parts per million, based upon the total composition, of a cure inhibitor.

Claim 33

The process of claim 17 wherein in the crosslinking polymer, R 2 HSiO 0 .5 is about 1.5, R"SiO 1 .5 is about 0.75 mole, and SiO 2 is about 1.0 mole.

Claim 34

The process of claims 17 or 31 wherein the crosslinking polymer, is ##STR15## where s and t are about 10 to about 2,000, and the amount of (CH 3 ) 2 HSi-- is equal to or greater than t, and the viscosity is about 30 centipoise to about 4,000 centipoise at 25° C.

Claim 35

The process of claims 17 or 31 wherein in the crosslinking polymer, R 2 HSiO 0 .5 is derived from dimethylchlorosilane; R"SiO 1 .5 is derived from trifluoropropyltrichlorosilane; and SiO 2 is derived from ethyl silicate.

Claim 36

The process of claim 17 wherein the resin (ii) is derived from the catalyzed hydrolysis of a blend of a trialkylhalosilane; a vinyldialkylhalosilane; a halosilane having at least one perfluorinated carbon atom and having the formula X 3 --Si(--CH 2 ) a R', where R' is perfluoroalkyl of 1 to about 8 carbon atoms, a is at least 2 but less than 10, (--CH 2 --) a is straight chain or branched and X is a halogen; and a condensed alkyl silicate.

Claim 37

The process of claim 34 wherein the perfluorinated halosilane is trifluoropropyltrichlorosilane.

Claim 38

The process of claim 34 wherein the trialkylhalosilane is trimethylchlorosilane.

Claim 39

The process of claim 34 wherein the vinyldialkylhalosilane is vinyldimethylchorosilane.

Claim 40

The process of claims 17 or 31 wherein the crosslinking polymer is ##STR16## where R and R' are defined in claim 1; s and t are at least 10; and x and z are zero, a positive integer or a combination thereof, and x+z is greater than t to provide a liquid polymer.