Curable silicone containing compositions and methods of making same

Abstract

A melt processable pseudointerpenetrating network of silicones in thermoplastic matrices and a method of producing same is provided by vulcanizing the silicones within the matrices. In a preferred embodiment a two part silicone comprising silicon hydride groups and silicon vinyl-containing groups are reacted in the presence of a platinum complex. Depending on certain parameters chain-extended (thermoplastic) or cross-linked (thermosetting) compositions are produced.

I claim: .[.1. A melt processable composition comprising a silicone component which will be vulcanized by the reaction of a hydride-containing silicone within a polymeric thermoplastic matrix to form a silicone pseudointerpenetrating polymer network, said vulcanization of said silicone component by reaction of said hydride-containing silicone being initiated during thermoplastic meltmixing of said component with said matrix..]. .[.2. A composition according to claim 1 wherein said silicone component ranges from between about 1 weight percent and about 40 weight percent based on the total weight of the composition..]. .[.3. A composition according to claim 1 wherein aid thermoplastic matrix is selected from the group consisting of polyamides, thermoplastic polyurethanes, bisphenol A polycarbonates, and polyacetals..]. .[.4. A composition according to claim 1 wherein said silicone component comprises the reaction product of a polymeric hydride group-containing silicone and polymeric silicone containing at least one unsaturated group..]. .[.5. A composition according to claim 4 wherein said unsaturated group comprises a vinyl group..]. .[.6. A composition according to claim 5 forming a predominantly chain-extended structure wherein said vinyl-containing silicone contains from about two to about four vinyl groups and wherein said hydride-containing silicone contains 1 to 2 times the equivalent of said vinyl-containing silicone with the ratio of said hydride groups to said vinyl groups being between about 1.2:1 and about 6:1..]. .[.7. A composition according to claim 5 wherein the vinyl-containing silicone has two vinyl groups in terminal positions..]. .[.8. A composition according to claim 5 forming a predominantly cross-linked structure wherein said vinyl-containing silicone contains from about two to about thirty vinyl groups and said hydride-containing silicone contains from two to ten times the equivalent of said vinyl-containing silicone with the ratio of the hydride groups to the vinyl groups being between about 1.2:1 and about 6:1..]. .[.9. A composition according to claim 4 wherein said silicone component further comprises constituents selected from the group consisting of methyl groups, phenyl groups, longer chain alkyl groups or 
     
        cyanopropyl groups..]. 10. A method for producing a silicone pseudointerpenetrating polymer network comprising vulcanizing a silicone component by the reaction of a hydride-containing silicone within a polymeric thermoplastic matrix at least partially during thermoplastic .[.meltmixing.]. .Iadd.melt-processing .Iaddend.of said silicone component 
     
     
        .[.with.]. .Iadd.and .Iaddend.said matrix. 11. A method according to claim 10 wherein said silicone component is the reaction product of a polymeric silicone containing hydride groups and a polymeric silicone containing at least one unsaturated group, said reaction conducted in the presence of a 
     
     
        catalyst. 12. A method according to claim 11 wherein said unsaturated 
     
     
        group is a vinyl group. 13. A method according to claim 11 wherein said 
     
     
        catalyst comprises a platinum complex. 14. A method according to claim 10 wherein said thermoplastic matrix is selected from the group consisting of polyamides, thermoplastic polyurethanes, bisphenol A polycarbonates, and 
     
     
        polyacetals. 15. A method according to claim 10 wherein a predominantly chain-extended structure is formed by combining a hydride-containing silicone and a vinyl-containing silicone with the vinyl-containing silicone having from about two to about four vinyl groups and the hydride-containing silicone contains 1 to 2 times the equivalent of the vinyl functionality with the ratio of the hydride groups to the vinyl groups being between about 1.2:1 and 6:1, adding a catalyst and .[.melt-mixing.]. .Iadd.melt-processing .Iaddend.the resultant mixture. 
     
     
            A method according to claim 15 wherein said .[.meltmixing.]. 
     
     
        .Iadd.melt-processing .Iaddend.comprises extrusion. 17. A method according to claim 15 wherein said .[.meltmixing.]. .Iadd.melt-processing 
     
     
        .Iaddend.is followed by pelletizing. 18. A method according to claim 11 further comprising conducting the reaction in the presence of fumed 
     
     
        silica. 19. A method according to claim 13 further comprising conducting 
     
     
        the reaction in the presence of vinyl siloxane. 20. A method according to claim 12 wherein predominantly cross-linked structure is formed by separately extruding the vinyl- and hydride-containing silicones into separate portions of said thermoplastic matrix, mixing the portions, adding a catalyst and .[.melting the portions together.]. .Iadd.melt-processing the mixture .Iaddend.so as to react the vinyl- and 
     
     
        hydride-containing silicones. 21. A method according to claim 12 wherein predominantly cross-linked structure is formed by extruding together the vinyl- and hydride-containing silicones into said thermoplastic matrix in the presence of a platinum catalyst and a fugitive inhibitor and .[.melt-mixing.]. .Iadd.melt-processing .Iaddend.the resultant mixture. 
     
     
            A method according to .[.claims.]. .Iadd.claim .Iaddend.20 .[.or 21.]. wherein the vinyl-containing silicone contains from about two to about thirty vinyl groups and the hydride-containing silicone contains from two to ten times the equivalent of the vinyl functionality with the ratio of the hydride groups to the vinyl groups being between about 1.2:1 and about 
     
     
        6:1. .Iadd.23.  A method according to claim 21 wherein the vinyl-containing silicone contains from about two to about 30 vinyl groups and the hydride-containing silicone contains from two to ten times the equivalent of the vinyl functionality with the ratio of the hydride groups to the vinyl groups being between about 1.2:1 and about 6:1. .Iaddend. 
     
     
        .Iadd.24.  A process according to claim 10 wherein said melt-processing comprises melt-mixing said silicone component and said matrix. .Iaddend. .Iadd.25. A process according to claim 15 wherein said melt-processing comprises melt-mixing. .Iaddend. .Iadd.26. A process according to claim 20 wherein said melt-processing comprises melting said portions of the mixture together. .Iaddend. .Iadd.27. A process according to claim 21 wherein said melt-processing comprises melt-mixing. .Iaddend. .Iadd.28. A melt processing composition comprising a polymeric thermoplastic matrix, a hydride group-containing silicone, and a component which will react with said hydride group-containing silicone, said silicone and said component being selected and present in sufficient amounts to react with each other by vulcanization within said polymeric thermoplastic matrix to form a silicone pseudo-interpenetrating polymer network, said vulcanization of said silicone and said component being initiated during thermoplastic 
     
     
        melt-processing of said composition. .Iaddend. .Iadd.29.  A composition according to claim 28 wherein said silicone network comprises about 1 to about 40 weight percent of the composition. .Iaddend. .Iadd.30. A composition according to claim 28 wherein said thermoplastic matrix is selected from the group consisting of polyamides, thermoplastic polyurethanes, bisphenol A polycarbonates, and polyacetals. .Iaddend. .Iadd.31. A composition according to claim 28 wherein said component which will react with said hydride group-containing silicone comprises a polymeric silicone containing at least one unsaturated group. .Iaddend. 
     
     
        .Iadd.32.  A composition according to claim 31 wherein said unsaturated group comprises a vinyl group. .Iaddend. .Iadd.33. A composition according to claim 32 forming a predominantly chain-extended structure wherein said vinyl-containing silicone contains from about 2 to about 4 vinyl groups and wherein said hydride group-containing silicone contains 1 to 2 times the equivalent of said vinyl-containing silicone with the ratio of said hydride groups to said vinyl groups being between about 1.2:1 and about 6:1. .Iaddend. .Iadd.34. A composition according to claim 32 wherein the vinyl-containing silicone has two vinyl groups in terminal positions. .Iaddend. .Iadd.35. A composition according to claim 32 forming a predominantly cross-linked structure wherein said vinyl-containing silicone contains from about 2 to about 30 vinyl groups and said hydride group-containing silicone contains from 2 to 10 times the equivalent of said vinyl-containing silicone with the ratio of the hydride groups to the vinyl groups being between about 1.2:1 and about 6:1. .Iaddend. .Iadd.36. A composition according to claim 31 wherein said silicone network further comprises constituents selected from the group consisting of methyl groups, phenyl groups, longer chain alkyl groups or cyanopropyl groups. .Iaddend. .Iadd.37. A composition according to claim 28 wherein said melt-processing comprises melt-mixing. .Iaddend. .Iadd.38. A composition according to claim 28 further comprising a catalyst to initiate said vulcanization. .Iaddend.