Silane scavengers for hydroxy radicals containing silicon-hydrogen bonds

Claim 1

A stable, one package, substantially anhydrous and substantially acid free, room temperature vulcanizable organopolysiloxane composition stable under ambient conditions in the substantial absence of moisture over an extended period of time and convertible to a tack-free elastomer, comprising: (A) a polydiorganosiloxane base polymer wherein the silicon atom at each chain end is terminated with at least two alkoxy radicals; (B) an effective amount of condensation catalyst; and (C) a stabilizing amount of scavenger for hydroxy functional groups selected from the group consisting of trimethoxysilane, triethoxysilane, methyldimethoxysilane, ethyldiethoxysilane, methyldiethoxysilane, ethyldimethoxysilane, dimethoxy(ethylmethylketoximo)silane, methylmethoxy(ethylmethylketoximo)silane, dimethoxy(N-methylcarbamato)silane, ethylmethoxy(N-methylcarbamato)silane, methylisopropenoxysilane, methylmethoxyisopropenoxysilane, dimethoxyisopropenoxysilane, methyldi-isopropenoxysilane, ethylmethoxy(N-ethylpropionamido)silane, methyldi(N-methylbenzamido)silane, dimethoxy(N-methylacetamido)silane, methyldimethoxyacetimidatosilane, methylmethoxy(N,N 1 ,N 1 -trimethylureido)silane, dimethoxyisocyanatosilane, ethylethoxyisocyanatosilane, methoxydiisocyanatosilane, dimethoxythioisocyanatosilane, tetramethyldisilane, tetramethyldisiloxane, dimethyldimethoxydisilane, dimethyldimethoxydisiloxane, tetramethyldimethoxytrisiloxane, tetraethyldimethoxytrisiloxane, 3-siloxytrisilthiane, silylthiodisiloxane, and silylthiodimethyldisiloxane.

Claim 11

A method for making a one package, substantially anhydrous and substantially acid-free room temperature vulcanizable composition curable to the solid elastomeric state, which method comprises agitating under substantially anhydrous conditions at a temperature in the range of from 0° C. to 180° C., a room temperature vulcanizable material selected from: (i) a mixture comprising: (a) 100 parts of a silanol terminated polydiorganosiloxane consisting essentially of chemically combined units of the formula: ##STR8## (b) an effective amount of a condensation catalyst, (c) a stabilizing amount of scavenger for hydroxy functional groups selected from the group consisting of trimethoxysilane, triethoxysilane, methyldimethoxysilane, ethyldiethoxysilane, methyldiethoxysilane, ethyldimethoxysilane, dimethoxy(ethylmethylketoximo)silane, methylmethoxy(ethylmethylketoximo)silane, dimethoxy(N-methylcarbamato)silane, ethylmethoxy(N-methylcarbamato)silane, methylisopropenoxysilane, methylmethoxyisopropenoxysilane, dimethoxyisopropenoxysilane, methyldiisopropenoxysilane, ethylmethoxy(N-ethylpropionamido)silane, methyldi(N-methylbenzamido)silane, dimethoxy(N-methylacetamido)silane, methyldimethoxyacetimidatosilane, methylmethoxy(N,N 1 ,N 1 -trimethylureido)silane, dimethoxyisocyanatosilane, ethylethoxyisocyanatosilane, methoxydiisocyanatosilane, dimethoxythioisocyanatosilane, tetramethyldisilane, tetramethyldisiloxane, dimethyldimethoxydisilane, dimethyldimethoxydisiloxane, tetramethyldimethoxytrisiloxane, tetraethyldimethoxytrisiloxane, 3-siloxytrisilthiane, silylthiodisiloxane, and silylthiodimethyldisiloxane, (d) an effective amount of a crosslinking silane of the formula: ##STR9## (e) 0-5 parts of a curing accelerator selected from the group consisting of substituted guanidines, amines and mixtures thereof; and (ii) a mixture comprising: (a) 100 parts of a polydiorganosiloxane base polymer wherein the silicon atom at each chain end is terminated with at least two alkoxy groups, (b) an effective amount of a condensation catalyst, (c) a stabilizing amount of scavenger for hydroxy functional groups selected from the group consisting of trimethoxysilane, triethoxysilane, methyldimethoxysilane, ethyldiethoxysilane, methyldiethoxysilane, ethyldimethoxysilane, dimethoxy(ethylmethylketoximo)silane, methylmethoxy(ethylmethylketoximo)silane, dimethoxy(N-methylcarbamato)silane, ethylmethoxy(N-methylcarbamato)silane, methylisopropenoxysilane, methylmethoxyisopropenoxysilane, dimethoxyisopropenoxysilane, methyldiisopropenoxysilane, ethylmethoxy(N-ethylpropionamido)silane, methyldi(N-methylbenzamido)silane, dimethoxy(N-methylacetamido)silane, methyldimethoxyacetimidatosilane, methylmethoxy(N,N 1 ,N 1 -trimethylureido)silane, dimethoxyisocyanatosilane, ethylethoxyisocyanatosilane, methoxydiisocyanatosilane, dimethoxythioisocyanatosilane, tetramethyldisilane, tetramethyldisiloxane, dimethyldimethoxydisilane, dimethyldimethoxydisiloxane, tetramethyldimethoxytrisiloxane, tetraethyldimethoxytrisiloxane, 3-siloxytrisilthiane, silylthiodisiloxane, and silylthiodimethyldisiloxane, (d) 0-10 parts of a crosslinking silane of the formula: ##STR10## (e) 0-5 parts of a curing accelerator selected from the group consisting of substituted guanidines, amines and mixtures thereof; where R 3 and R 8 are independently selected monovalent substituted or unsubstituted hydrocarbon radicals having 1 to 13 carbon atoms, R 7 is a C.sub.(1-8) aliphatic organic radical selected from the group consisting of alkyl, alkylether, alkylester, alkylketone and alkylcyano radicals or a C.sub.(7-13) aralkyl radical and h equals 0 or 1.

Claim 12

A method for making a one package, substantially anhydrous and substantially acid-free room temperature vulcanizable composition curable to the solid elastomeric state, which method comprises agitating under substantially anhydrous conditions at a temperature in the range of from 0° C. to 180° C., a room temperature vulcanizable material selected from: (i) a mixture comprising: (a) 100 parts of a silanol terminated polydiorganosiloxane consisting essentially of chemically combined units of the formula: ##STR8## (b) an effective amount of a condensation catalyst, (c) a stabilizing amount of scavenger for hydroxy functional groups selected from the group consisting of trimethoxysilane, triethoxysilane, methyldimethoxysilane, ethyldiethoxysilane, methyldiethoxysilane, ethyldimethoxysilane, dimethoxy(ethylmethylketoximo)silane, methylmethoxy(ethylmethylketoximo)silane, dimethoxy(N-methylcarbamato)silane, ethylmethoxy(N-methylcarbamato)silane, methylisopropenoxysilane, methylmethoxyisopropenoxysilane, dimethoxyisopropenoxysilane, methyldiisopropenoxysilane, ethylmethoxy(N-ethylpropionamido)silane, methyldi(N-methylbenzamido)silane, dimethoxy(N-methylacetamido)silane, methyldimethoxyacetimidatosilane, methylmethoxy(N,N 1 ,N 1 -trimethylureido)silane, dimethoxyisocyanatosilane, ethylethoxyisocyanatosilane, methoxydiisocyanatosilane, dimethoxythioisocyanatosilane, tetramethyldisilane, tetramethyldisiloxane, dimethyldimethoxydisilane, dimethyldimethoxydisiloxane, tetramethyldimethoxytrisiloxane, tetraethyldimethoxytrisiloxane, 3-siloxytrisilthiane, silylthiodisiloxane, and silylthiodimethyldisiloxane, (d) an effective amount of a crosslinking silane of the formula: ##STR9## (e) 0-5 parts of a curing accelerator selected from the group consisting of substituted guanidines, amines and mixtures thereof; and (ii) a mixture comprising: (a) 100 parts of a polydiorganosiloxane base polymer wherein the silicon atom at each chain end is terminated with at least two alkoxy groups, (b) an effective amount of a condensation catalyst, (c) a stabilizing amount of scavenger for hydroxy functional groups selected from the group consisting of trimethoxysilane, triethoxysilane, methyldimethoxysilane, ethyldiethoxysilane, methyldiethoxysilane, ethyldimethoxysilane, dimethoxy(ethylmethylketoximo)silane, methylmethoxy(ethylmethylketoximo)silane, dimethoxy(N-methylcarbamato)silane, ethylmethoxy(N-methylcarbamato)silane, methylisopropenoxysilane, methylmethoxyisopropenoxysilane, dimethoxyisopropenoxysilane, methyldiisopropenoxysilane, ethylmethoxy(N-ethylpropionamido)silane, methyldi(N-methylbenzamido)silane, dimethoxy(N-methylacetamido)silane, methyldimethoxyacetimidatosilane, methylmethoxy(N,N 1 ,N 1 -trimethylureido)silane, dimethoxyisocyanatosilane, ethylethoxyisocyanatosilane, methoxydiisocyanatosilane, dimethoxythioisocyanatosilane, tetramethyldisilane, tetramethyldisiloxane, dimethyldimethoxydisilane, dimethyldimethoxydisiloxane, tetramethyldimethoxytrisiloxane, tetraethyldimethoxytrisiloxane, 3-siloxytrisilthiane, silylthiodisiloxane, and silylthiodimethyldisiloxane, (d) 0-10 parts of a crosslinking silane of the formula: ##STR10## (e) 0-5 parts of a curing accelerator selected from the group consisting of substituted guanidines, amines and mixtures thereof; where R 3 and R 8 are independently selected monovalent substituted or unsubstituted hydrocarbon radicals having 1 to 13 carbon atoms, R 7 is a C.sub.(1-8) aliphatic organic radical selected from the group consisting of alkyl, alkylether, alkylester, alkylketone and alkylcyano radicals or a C.sub.(7-13) aralkyl radical and h equals 0 or 1.