Room temperature vulcanizable polysiloxane having a heat-activated catalyst

Claim 2

A two-component room temperature vulcanizable polysiloxane composition curable in the presence of a heat-activated catalyst comprising: (A) 100 parts by weight of a mixture comprised of: (i) an organopolysiloxane containing terminal silicon-bonded hydroxy groups; (ii) optionally, a cross linking-agent; and (iii) optionally, a filler; and (B) about 5 to about 15 parts by weight of a catalyst-containing component comprised of: (iv) a catalyst comprising a metallic salt of an organic carboxylic acid in which the metal ion is selected from the group consisting of lead to manganese in the periodic table of the elements, the catalyst being in combination with a solid, inert barrier material which is a metallic salt of an orgaic carboxylic acid in which the metal ion is selected from the group consisting of zinc, cobalt, manganese, nickel and calcium, which in combination with the organic carboxylic acid radical does not promote catalytic action at room temperature, but which solid, inert barrier material is capable of melting at elevated temperature, whereby the catalyst is activated when heat applied thereto melts the solid barrier material; (v) about 1.5 to about 20.0 weight percent of component (B) of a cross-linking agent; (vi) about 5 to about 50 weight percent of component (B) of a filler; and (vii) about 5.0 to about 50.0 weight percent of component (B) of a polyorganosiloxane having no silanol-stopped terminal groups.

Claim 3

A two-component room temperature vulcanizable polysiloxane composition curable in the presence of a heat-activated catalyst comprising: (A) 100 parts by weight of a mixture comprised of: (i) an organopolysiloxane containing terminal silicon-bonded hydroxy groups; (ii) optionally, a cross-linking agent; (iii) up to about 50 weight percent of component (A) of a filler; and (B) about 5 to about 15 parts by weight of a catalyst-containing component comprised of: (iv) a catalyst comprised of solid particles of a metal salt of an organic carboxylic acid in which the metal ion is selected from the group consisting of tin, lead, zirconium, antimony, iron, cadmium, barium, calcium, titanium, bismuth and manganese, as a core material, and a solid, inert barrier material which is a metallic salt of an organic carboxylic acid in which the metal ion is selected from the group consisting of zinc, cobalt, manganese, nickel and calcium, which in combination with the organic carboxylic acid radical does not promote room temperature curing, but which solid, inert barrier is capable of melting at an elevated temperature, as a coating material on the core material, whereby the coating material melts when heat is applied thereto and releases the core catalyst material; (v) about 1.5 to about 20.0 weight percent of component (B) of a cross-linking agent; (vi) about 5 to about 50 weight percent of component (B) of a filler; and (vii) about 5.0 to about 50.0 weight percent of component (B) of an alkyl-stopped organopolysiloxane carrier.

Claim 4

A two-component room temperature vulcanizable polysiloxane composition curable in the presence of a heat-activated catalyst comprising: (A) 100 parts by weight of a mixture comprised of: (i) an organopolysiloxane containing terminal silicon-bonded hydroxy groups; (ii) optionally, a cross-linking agent; (iii) up to about 50 weight percent of component (A) of a filler; and (B) about 5 to about 15 parts by weight of a catalyst-containing component comprised of: (iv) a catalyst comprised of solid particles of a metal salt of an organic carboxylic acid in which the metal ion is selected from the group consisting of tin, lead, zirconium, antimony, iron, cadmium, barium, calcium, titanium, bismuth and manganese, as a core material, and a solid, inert barrier material which is a metallic salt of an organic carboxylic acid in which the metal ion is selected from the group consisting of zinc, cobalt, manganese, nickel and calcium, which in combination with the organic carboxylic acid radical does not promote room temperature curing, but which solid, inert barrier is capable of melting at an elevated temperature, as a coating material on the core material, whereby the coating material melts when heat is applied thereto and releases the core catalyst material; (v) about 1.5 to about 20.0 weight percent of component (B) of a cross-linking agent; (vi) about 5 to about 50 weight percent of component (B) of a filler; and (vii) about 5.0 to about 50.0 weight percent of component (B) of an alkyl-stopped organopolysiloxane carrier.

Claim 5

The two-component room temperature vulcanizable polysiloxane composition of claims 1 or 2 wherein the organic carboxylic acid salt of the solid, inert barrier material of (B)(iv) is selected from the group consisting of octoate, naphthenate, stearate and oleate.

Claim 6

The two-component room temperature vulcanizable polysiloxane composition of claims 1 or 2 wherein the solid inert barrier material of (B)(iv) is calcium stearate, and the catalyst of (B)(iv) is a tin carboxylate.

Claim 7

The two-component room temperature vulcanizable polysiloxane composition of claims 1 or 2 wherein the catalyst is the metallic salt of an organic monocarboxylic acid or the metallic salt of an organic dicarboxylic acid.

Claim 8

The two-component room temperature vulcanizable polysiloxane composition of claims 1 or 2 wherein the catalyst is selected from the group consisting of the formula: ##STR10## the formula: ##STR11## where R and R 1 are alkyl radicals of 1 to about 20 carbon atoms, substituted alkyl radicals of 1 to about 8 carbon atoms, aromatic groups of about 6 to about 18 carbon atoms and substituted aromatic groups of about 6 to about 18 carbon atoms.

Claim 9

The two-component room temperature vulcanizable polysiloxane composition of claims 1 or 2 wherein the cross-linking agent is an organic silicate.

Claim 10

The two-component room temperature vulcanizable polysiloxane composition of claims 1 or 2 wherein the cross-linking agent is condensed ethyl silicate.

Claim 11

The two-component room temperature vulcanizable polysiloxane composition of claims 1 or 2 further comprising an anti-oxidant to prevent oxidation of the catalyst.

Claim 12

The cured compostion obtained from a mixture of the ingredients of claims 1 or 2.

Claim 17

The method of claim 11 wherein the metal ion of the metallic salt of an organic carboxylic acid catalyst is selected from the group consisting of tin, lead, zirconium, antimony, iron, cadmium, barium, calcium, titanium, bismuth, and manganese.

Claim 26

The method of claim 12 wherein the cross-linking agent is an organic silicate.

Claim 27

The method of claim 22 wherein the organic silicate cross-linking agent is condensed ethyl silicate.

Claim 28

The method claim 12 wherein the non-hydroxy terminated organopolysiloxane is an alkyl-stopped organopolysiloxane.

Claim 29

The method of claim 24 wherein the alkyl-stopped organopolysiloxane is a methyl-stopped organopolysiloxane.

Claim 30

The method of claim 24 wherein the alkyl-stopped organopolysiloxane is a vinyl-stopped organopolysiloxane.

Claim 31

The method of claim 12 wherein the cross-linking agent of component (B)(v) is about 6.0 to about 20 weight percent of component (B).

Claim 32

A process for forming a cured room temperature vulcanizable, condensation-curable organopolysiloxane, comprising: mixing (A) 100 parts by weight of a first component comprised of (i) a base organopolysiloxane containing terminal silicon-bonded hydroxy groups, (ii) optionally, a cross-linking agent; and (iii) optionally, a filler; with (B) about 5 to about 15 parts by weight of a catalyst-containing second component comprised of (iv) a catalyst comprising a metallic salt of an organic carboxylic acid in which the metal ion is selected from the group consisting of tin, lead, zirconium, antimony, iron, cadmium, barium, calcium, titanium, bismuth and manganese, the catalyst being in combination with a solid, inert barrier material which is a metallic salt of an organic carboxylic acid in which the metal ion is selected from the group consisting of zinc, cobalt, manganese, nickel and calcium, which in combination with the organic carboxylic acid radical does not promote catalytic action at room temperature, but which solid, inert barrier material is capable of melting at an elevated temperature, whereby the catalyst is activated when heat applied thereto melts the solid barrier material; (v) about 1.5 to about 20.0 weight percent of component (B) of a cross-linking agent; (vi) about 5 to about 50 weight percent of component (B) of an organopolysiloxane having no silanol-stopped terminal groups; and heating the mixture at an elevated temperature sufficient to melt the solid, inert barrier material, thereby releasing the catalyst; and allowing the mixture to cure in the presence of the catalyst.

Claim 33

A process for forming a cured room temperature vulcanizable, condensation-curable organopolysiloxane, comprising: mixing (A) 100 parts by weight of a first component comprised of (i) a base organopolysiloxane containing terminal silicon-bonded hydroxy groups, (ii) optionally, a cross-linking agent; and (iii) optionally, a filler; with (B) about 5 to about 15 parts by weight of a catalyst-containing second component comprised of (iv) a catalyst comprising a metallic salt of an organic carboxylic acid in which the metal ion is selected from the group consisting of tin, lead, zirconium, antimony, iron, cadmium, barium, calcium, titanium, bismuth and manganese, the catalyst being in combination with a solid, inert barrier material which is a metallic salt of an organic carboxylic acid in which the metal ion is selected from the group consisting of zinc, cobalt, manganese, nickel and calcium, which in combination with the organic carboxylic acid radical does not promote catalytic action at room temperature, but which solid, inert barrier material is capable of melting at an elevated temperature, whereby the catalyst is activated when heat applied thereto melts the solid barrier material; (v) about 1.5 to about 20.0 weight percent of component (B) of a cross-linking agent; (vi) about 5 to about 50 weight percent of component (B) of an organopolysiloxane having no silanol-stopped terminal groups; and heating the mixture at an elevated temperature sufficient to melt the solid, inert barrier material, thereby releasing the catalyst; and allowing the mixture to cure in the presence of the catalyst.

Claim 34

The process of claim 28 wherein the organic carboxylic acid radical of the inert, barrier material is selected from the group consisting of octoate, naphthenate, stearate and oleate.

Claim 35

The process of claim 28 wherein the solid, inert barrier material is calcium stearate, and the catalyst is a tin carboxylate.

Claim 36

The process of claim 28 wherein the catalyst is the metallic salt of an organic monocarboxylic acid.

Claim 37

The process of claim 28 wherein the catalyst is the metallic salt of an organic dicarboxylic acid.

Claim 38

The process of claim 28 wherein the catalyst is selected from the group consisting of the formula: ##STR14## the formula: ##STR15## where R and R 1 are alkyl radicals of 1 to about 20 carbon atoms, substituted alkyl radicals of 1 to about 8 carbon atoms, aromatic groups of about 6 to about 18 carbon atoms and substituted aromatic groups of about 8 to about 18 carbon atoms.

Claim 39

The process of claim 28 wherein the cross-linking agent is an organic silicate.

Claim 40

The process of claim 28 wherein the organic silicate cross-linking agent is condensed ethyl silicate.

Claim 41

The process of claim 28 further comprising adding an anti-oxidant to prevent oxidation of the catalyst.

Claim 42

The process of claim 28 further comprising mixing a coloring agent in at least one of the components.