Abstract: Room temperature vulcanizable platinum group metal catalyzed silicone compositions are provided which utilize an N-heterocyclic adhesion promoter, such as 2,6 bis(trimethoxysilyltrimethyleneoxy)pyridine. Cohesive bonding is effected on various substrates.

Abstract: Adhesion promoting compositions for bonding a layer of organic polymer to a layer of organosiloxane elastomer during curing of the elastomer by a platinum group metal-catalyzed hydrosilation reaction comprise (a) a copolymer containing repeating units derived from at least one ethylenically unsaturated organic compound and at least one silane containing an ethylenically unsaturated organic group and at least two silicon-bonded hydrolyzable groups per molecule, and (b) an organohydrogensiloxane containing an average of at least three silicon-bonded hydrogen atoms per molecule. If the adhesion promoting composition is to be used with an elastomer prepared by curing an organosiloxane elastomer at temperatures below about 80 degrees C., the adhesion promoting composition includes an alkyl orthosilicate and an organotitanium compound.

Abstract: The composition of the present invention comprises an oil-resistant silicone rubber composition that undergoes little swelling even when used in regular or continuous contact with mineral oil-based lubricating oil such as engine oil and so forth. The oil-resistant silicone rubber composition comprises:(A) a dimethylsiloxane-3,3,3-trifluoropropylmethylsiloxane-methylvinylsiloxane copolymer gum that contains 0.001 to 5 mole percent methylvinylsiloxane unit,(B) a hydrocarbon oil or diorganopolysiloxane oil wherein the total in each diorganopolysiloxane oil molecule of the number of silicon-bonded hydrogen atoms and the number of functional groups reactive with component (A) or (C) is less than two,(C) a reinforcing filler, and(D) a curing agent in a quantity sufficient to cure the composition.

Abstract: The present invention relates to a silicone rubber microsuspension which has an excellent high-concentration storage stability, and to a method for the preparation of a silicone rubber microsuspension. The silicone rubber microsuspension comprises a microparticulate silicone rubber having an average particle diameter not exceeding 10 micrometers, a nonionic surfactant whose HLB value is less than 10, a nonionic surfactant whose HLB value is at least 10, and water, with the proviso that the content of the microparticulate silicone rubber in the silicone rubber microsuspension is at least 50 weight percent. The method for the preparation of said silicone rubber microsuspension comprises mixing a liquid silicone rubber composition, a nonionic surfactant having an HLB value of less than 10, a nonionic surfactant having an HLB value of at least 10, and water.

Abstract: A impression composition comprising:(A) a polyether polymer having at least two alkenyl groups in its molecule,(B) a polyorganohydrogensiloxane having at least three silicon-bonded hydrogen atoms in its molecule,(C) a platinum catalyst,(D) an inorganic filler, and(E) an antioxidant.This composition of has hydrophilic nature and a small cure shrinkage; hence it enables precise impression in a wet environment like in a mouth.

Abstract: A thermosetting printing ink composition comprising a functional copolymer of a thermosettable polyester and a polysiloxane, a pigment, a crosslinking agent and a curing catalyst which may be a strong acid or a metal salt thereof. The composition desirably also includes a reactive diluent such as a glycol, glycol ether or alcohol. The compositions are especially useful for imprinting metal containers such as beer and soda cans.

Abstract: A shelf stable aqueous silicone emulsion which yields an elastomer upon removal of the water is produced by combining a reactive polydiorganosiloxane present as an cationic or nonionic emulsion of dispersed particles in water, an acyloxysilane crosslinker, and a tin catalyst, the tin catalyst being in the form of a divalent tin atom combined with organic radicals. The emulsion can be reinforced with colloidal silica without effecting the shelf life of the reinforced emulsion.

Abstract: The instant invention pertains to viscous fluid coupling organopolysiloxane compositions comprised of (A) at least one organopolysiloxane fluid that has the general formula R.sup.1.sub.a R.sup.2.sub.b SiO.sub.[4-(a+b)]/2 wherein R.sup.1 is an alkyl group, R.sup.2 is an aryl group, a+b has the value of 1.95 to 2.05, and b/(a+b) has the value of 0.05 to 0.30; and (B) 0.01 to 5 weight parts by weight per 100 parts by weight of component (A) of a compound with the general formula ##STR1## wherein each R.sup.3 is independently selected from an alkyl group and C has the value of 0 to 2. The viscous fluid coupling organopolysiloxane compositions of the instant invention are capable of withstanding long-term use and under high-temperature, high-shear conditions with little increase or decrease in viscosity and almost no torque fluctuation.

Abstract: The present invention provides a heat-curable silicone rubber composition to be cured by hydrosilation reactions and having outstanding physical properties, especially a high tear strength, said composition comprising(A) a polydiorganosiloxane having at least two unsaturated aliphatic hydrocarbon groups and represented by the general formula (1):R.sub.a.sup.1 SiO.sub.(4-a)/2 ( 1)wherein R.sup.1 represents a substituted or unsubstituted monovalent hydrocarbon group containing 0.01 to 15 mole % of an unsaturated aliphatic hydrocarbon group, a is a positive number of from 1.95 to 2.05.(B) a polyorganohydrogensiloxane having at least three hydrogen atoms directly bonded to silicon atom in a molecule,(C) silica filler having a specific surface area of at least 50 m.sup.2 /g, and(D) an addition reaction catalyst,(E) water, and preferably(F) an organosilane represented by the general formula:R.sub.m.sup.2 Si(OR).sub.4-mwherein R.sup.

Abstract: Disclosed are flame retardant organosilicon compositions, wherein the organosilicon compositions comprise residues derived from (a) polycyclic polyene compounds and (b) residues derived from cyclic polysiloxanes, tetrahedral siloxysilanes and linear poly(organohydrosiloxane)s. Preferably the compositions contain flame retardants, such as a phosphorus containing or halogen containing flame retardant, which may be microencapsulated. Also disclosed are processes for making such compositions and articles made from such compositions.

Abstract: A mold-releasable curable organopolysiloxane composition suitable for use as a material of a matrix mold having excellent durability of mold releasability in the preparation of replicas by resin casting is disclosed. The composition comprises, in addition to the conventional ingredients including a vinyl-containing diorganopolysiloxane, an organohydrogenpolysiloxane as a crosslinking agent of the diorganopolysiloxane, a reinforcing silica filler and a platinum compound as a catalyst, a strongly alkaline compound of an alkali metal such as potassium hydroxide, potassium siliconate, lithium siliconate and the like in a limited amount.

Abstract: A process for preparing organopolysiloxane hydrosols by mixing an organosilicon compound with water, which comprises mixing a silane of the formulaR.sub.a Si(OR.sup.1).sub.4-a (I)where a is 0, 1, 2 or 3, R can be the same or different and is a hydrogen atom or a monovalent organic radical, R.sup.1 can be the same or different and is a monovalent organic radical, and/or a partial hydrolysis product thereof and, optionally, an organodisiloxane of the formulaR.sup.2.sub.3 Si-O-SiR.sup.2.sub.3 (II)where R.sup.2 can be the same or different and is the same as R, with water in the presence of an emulsifier at a temperature below 15.degree. C.

Abstract: Adhesive compositions of this invention are characterized by the addition of certain silane compounds as adhesion promoters to addition curing type compositions which comprise a diorganopolysiloxane containing alkenyl groups bonded to silicon atoms and an organohydrogen polysiloxane containing hydrogen atoms bonded to silicon atoms, wherein the adhesion promoting silane compound, is of the formula: ##STR1## wherein R.sup.1 and R.sup.2 are either hydrogen atoms or lower alkyl groups, R.sup.3 and R.sup.4 are preferably lower alkyl groups and a and n are integers from 0 to 2.

Abstract: A curable silicone composition which can cure using hydrosilylation, comprising an aluminum oxide powder and/or silica powder, the powders each consisting of substantially spherical particles with an average particle diameter of 50 .mu.m or below and an elongation of from 1.0 to 1.4 and being such that the respective amounts of alkali metal ions and halogen ions are extracted with 50 ml of water from 5 g of the powder at 121.degree. C. for 20 hours are not more than 10 ppm, wherein the amount of the component (D) is from 25 to 90% by weight based on the composition, and the ratio of the amount of hydrosilyl groups contained in the components (A) and (B) to the amount of alkenyl groups contained in the components (A) and (B) is in the range from 0.5/1 to 1.5/1. When the composition is used as a protective material or encapsulating material for devices such as ICs, generated heat can be dissipated efficiently and the devices are not be broken by abrasion. There are no fears of causing corrosion of the devices.

Abstract: Silicone compositions comprising an organopolysiloxane composition and an organic compound capable of coordination with metals are described. Since the organic compound is preferentially adsorbed on a metal surface, the composition is particularly suitable for use in electric or electronic parts to prevent contact failure. A more specific embodiment comprises a diorganopolysiloxane of the average unit formula, R.sub.a SiO.sub.(4-a)/2, wherein each R independently represents an unsubstituted or substituted monovalent hydrocarbon group, and a is a value of from 1.90 to 2.05, a filler, an alkoxysilane or its hydrolyzate, a silylation catalyst made of an organic silicon compound having at least one specific type of group, an organic tin compound, another organosilicon compound capable of reaction with an alcohol in order to stabilize the composition, and an organic compound capable of coordination with metals.

Abstract: A silicone rubber composition having excellent workability and extrusion-moldability and capable of giving cured silicone rubber articles having good mechanical properties is proposed, which is prepared by admixing, in addition to the conventional ingredients of an organopolysiloxane gum, a finely divided reinforcing silica filler and a curing agent such as an organic peroxide, a low molecular-weight organopolysiloxane having, in a molecule, at least three silanolic hydroxy groups which serves as a wetting agent of the silica filler so as to improve the compatibility of the silica filler with the organopolysiloxane gum giving a possibility of increasing the amount of the silica filler without adverse influences such as a decrease in the plasticity of the composition.

Abstract: A hydrophobic silica is prepared by mixing and heating a mixture of (a) 100 weight parts wet-method silica and (b) 1 to 100 weight parts organopolysiloxane represented by the following average unit formula R.sup.1.sub.a R.sup.2.sub.b SiO.sub.(4-a-b)/2, wherein R.sup.1 is a monovalent hydrocarbon group, R.sup.2 is the hydrogen atom, a is from 1 to 3 inclusive, and b is from zero to 1 inclusive, with the provisos that a+b is from 1.90 to 2.10 inclusive and b/(a+b) is from zero to 0.45 inclusive. This hydrophobic silica is used to prepare a high-strength silicone rubber particulate by mixing with a curable dioranopolysiloxane and curing the mixture in the form of particulates. A preferred manner of making the particulates is by emulsifying the mixture of hydrophobic silica and curable diorganopolysiloxane in water, then spraying the emulsion into a hot gas to cure the silicone rubber composition and remove the water, giving microparticles of high-strength silicone rubber.

Abstract: A composition and method for rendering a surface water repellent. The composition is a substantially solvent-free organoalkoxysilane having between two and nine silicon atoms per silane. An oleophobic organofluoro compound may be added to the composition in order to render the surface also oil repellent.

Abstract: A release silicone emulsion composition comprising:(A) 100 parts by weight of a specific organovinylpolysiloxane;(B) from 1 to 50 parts by weight of a specific organohydrogenpolysiloxane;(C) from 0.5 part to 5 parts by weight of a platinum catalyst having a viscosity of 10 cSt or less at 25.degree. C.;(D) from 1.5 to 15 parts by weight of a nonionic emulsifying agent having an average HLB of from 10 to 20, pH of 6.5 or less and an ionic conductivity of 30 .mu..OMEGA..sup.-1 cm.sup.-1 or less; and(E) water.This composition has good pot life and curability. The cured film had good release properties and residual adhesive properties of adhesives.

Abstract: A silicone sealant prepared by curing and cross-linking methylhydrosiloxanes by contacting and forming a mixture of an allyl amide or an allyl ester with at least one methylhydrosiloxane in the presence of a Group VIII metal catalyst, and heating the mixture of the allyl amide, the methylhydrosiloxane, a filler, and the Group VIII metal catalyst, in the presence of ambient moisture until the methylhydrosiloxane becomes cured and cross-linked.

Abstract: The curable resin composition of the present invention consists of a curable resin having uniformly dispersed therein particles of a cured silicone rubber obtained from an organosiloxane composition curable by a platinum-catalyzed hydrosilation reaction, wherein said organosiloxane composition contains reaction products of an ethylenically unsaturated epoxy compound and an ethylenically unsaturated aromatic compound with the organohydrogenpolysiloxane present in said organosiloxane composition. Either or both of the epoxy compound and the aromatic compound can be prereacted with a portion of the silicon-bonded hydrogen atoms of the organohydrogenpolysiloxane.

Abstract: The silacyclobutane functional polydiorganosiloxane copolymers of the invention have the following structure: ##STR1## wherein M is selected from ##STR2## wherein R.sup.a, R.sup.b, R.sup.c, R.sup.d, R.sup.e, and R.sup.f are independently monovalent radicals selected from the group consisting of hydrogen, hydrocarbon, or substituted hydrocarbon; m and x are integers of from 0 or more; n is equal to 1; and p is an integer greater than 0; with the proviso that there is at least one silacyclobutane group in the copolymer. The copolymer can be made by reacting a hydroxyl endblocked polydiorganosiloxane with either a difunctional chain extending silacyclobutane or with a monofunctional chain stopper, or a mixture of chain extender and chain stopper. The copolymer can be made into curable compositions by use of suitable catalyst.

Abstract: The present invention provides a relatively simple synthesis procedure for the formation of silane hydrolyzate compositions of the formula ##EQU1## where R is hydrogen or a methyl group, n is an integer greater than about 8, and x is a number between 0 and 2. The hydrolyzate compositions are metastable in solvent solution, but become insoluble after coating on a substrate. The resins are useful as planarizing coatings for substrates such as electronic devices and can be ceramified by subjecting them to an oxidizing atmosphere at a temperature of between about 100.degree. to 1000.degree. C. to form ceramic or ceramic-like coatings on such substrates.

Abstract: A method of obtaining an aqueous silicone emulsion which dries to an elastomer comprises mixing (1) hydroxyl endblocked polydiorganosiloxane free of aliphatic unsaturation, (2) silicon hydride crosslinker, (3) platinum compound catalyst compatible with the polydiorganosiloxane, (4) catalyst inhibitor, (5) anionic or nonionic surfactant, and (6) water and polymerizing the polydiorganosiloxane. These ingredients can be combined in emulsion form following three differing versions of a method of combining the ingredients and polymerizing the polydiorganosiloxane. In each case, the emulsion, which may also contain filler, is useful as a coating or sealant.

Abstract: A method of obtaining an aqueous silicone emulsion which dries to an elastomer comprises mixing (1) hydroxyl endblocked polydiorganosiloxane free of aliphatic unsaturation, (2) silicon hydride crosslinker, (3) platinum compound catalyst compatible with the polydiorganosiloxane, (4) catalyst inhibitor, (5) anionic or nonionic surfactant, and (6) water and polymerizing the polydiorganosiloxane. These ingredients can be combined in emulsion form following three differing versions of a method of combining the ingredients and polymerizing the polydiorganosiloxane. In each case, the emulsion, which may also contain filler, is useful as a coating or sealant.

Abstract: A method of obtaining an aqueous silicone emulsion which dries to an elastomer comprises mixing (1) hydroxyl endblocked polydiorganosiloxane free of aliphatic unsaturation, (2) silicon hydride crosslinker, (3) platinum compound catalyst compatible with the polydiorganosiloxane, (4) anionic or nonionic surfactant, and (5) water and polymerizing the polydiorganosiloxane. These ingredients can be combined in emulsion form following three differing versions of a method of combining the ingredients and polymerizing the polydiorganosiloxane. In each case, the emulsion, which may also contain filler, is useful as a coating or sealant.

Abstract: An excellently pleasant feeling of softness and elastic resilience can be imparted to a fabric material treated with the inventive fabric finishing agent which is an aqueous emulsion of a copolymer obtained by the emulsion polymerization, in an aqueous emulsion of an organopolysiloxane having radical-polymerizable groups, e.g., vinyl groups, or mercapto-substituted hydrocarbon groups, e.g., 3-mercaptopropyl groups, as the polymerization medium of an acrylic or methacrylic monomer, e.g., alkyl acrylates and methacrylates, in a specified amount relative to the amount of the organopolysiloxane. The acrylic or methacrylic monomer may be partly replaced with a polyfunctional monomer, e.g., acrylic and methacrylic acids, N-methylol acrylamide, glycidyl methacrylate, 2-hydroxyethyl methacrylate and the like, and/or a monomer of the third class, e.g., styrene and acrylonitrile. The emulsion may be further admixed with an organohydrogen polysiloxane as a crosslinking agent and a catalyst for the crosslinking reaction.

Abstract: What is disclosed and claimed are organopolysiloxanes having liquid crystalline properties at relatively low temperatures as compared to prior art materials. The organopolysiloxanes have this property by virtue of a unique chemical spacer between the siloxane and the mesogenic groups, which spacers are oxyalkylene groups.

Abstract: A method of obtaining an aqueous silicone emulsion which dries to an elastomer comprises mixing (1) hydroxyl endblocked polydiorganosiloxane free of aliphatic unsaturation, (2) silicon hydride crosslinker, (3) platinum compound catalyst compatiable with the polydiorganosiloxane, (4) catalyst inhibitor, (5) anionic or nonionic surfactant, and (6) water and polymerizing the polydiorganosiloxane. These ingredients can be combined in emulsion form following three differing versions of a method of combining the ingredients and polymerizing the polydiorganosiloxane. In each case, the emulsion, which may also contain filler, is useful as a coating or sealant.

Abstract: Storage-stable, curable polyorganosiloxane compositions, whether solvent-free, in solution in an organic solvent or in aqueous emulsion, contain (A) a polydiorganosiloxane having silanol endgroups, (B) a polydiorganohydrosilane, and (C) a catalytically effective amount of a latent tin catalyst of the formula (1): ##STR1## and are cured into elastomeric state by heating to a temperature at least equal to the decomposition temperature of the latent catalyst (C); such polyorganosioxane compositions are well adopted for the thin-layer coating of a wide variety of useful substrates, e.g., paper.

Abstract: Extrudable organosiloxane compositions that cure by a hydrosilation reaction comprise a first polydiorganosiloxane containing alkenyl radicals only at the terminal positions of each molecule and a second polydiorganosiloxane containing alkenyl radicals on both terminal and non-terminal silicon atoms. When the alkenyl radicals on at least the second of the two polydiorganosiloxanes contain at least four carbon atoms the cure rate of the compositions is substantially increased relative to compositions wherein the alkenyl radicals on this polymer are vinyl.

Abstract: The presence of a vinyl-specific peroxide in liquid organosiloxane compositions curable to elastomers by a platinum-catalyzed hydrosiliation reaction imparts excellent recovery properties to the elastomers without requiring post-curing. To avoid premature curing the compositions are preferably stored and transported in at least two parts, where the organohydrogensiloxane curing agent and the hydrosilation catalyst are located in different parts of the composition.

Abstract: Compositions which can be crosslinked by radiation to form elastomers comprising (a) an organopolysiloxane containing triorganosiloxane units of the formulaH.sub.2 C=CHCXOR.sup.1 SiR.sub.2 O.sub.1/2in which R is selected from monovalent hydrocarbon radicals and halogenated monovalent hydrocarbon radicals, R.sup.1 is selected from divalent hydrocarbon radicals and divalent halogenated hydrocarbon radicals and X is selected from oxygen and sulfur, in which at least 80 percent of the siloxane units other than the triorganosiloxane units are diorganosiloxane units, where the SiC-bonded organic radicals of the triorganosiloxane units and the diorganosiloxane units are selected from monovalent hydrocarbon radicals and halogenated monovalent hydrocarbon radicals, (b) a filler having a surface area of at least 50 m.sup.

Abstract: A release agent composition which manifests almost no silicone migration and a very low slickness while nevertheless having a low release value is achieved by means of a release agent composition which is based on a methylalkenylpolysiloxane, an alkylhydrogenpolysiloxane crosslinker for the methylalkenylpolysiloxane, an organopolysiloxane containing monovalent hydrocarbon groups which lacks aliphatically unsaturated bonds and which contains 6 to 18 carbon atoms which functions to lighten the releaseability of the cured film, to check silicone migration, and to reduce the slickness, and a catalytic quantity of a platinum-type catalyst.

Abstract: An addition or condensation cross-linking molding or lining compound based on silicones comprising(a) an organo polysiloxane containing reactive end groups,(b) a catalyst,(c) a filler, and(d) an isoparaffin having 8 to 24 carbon atoms.The compounds being particularly useful as dental molding compositions.

Abstract: The curable resin composition of the present invention consists of a curable resin and the spherical microparticles of cured silicone rubber obtained by the curing of an addition reacting silicone rubber composition, wherein the silicone rubber composition also contains an epoxy compound having an aliphatically unsaturated group. Furthermore, because the microparticles are prepared from an aqueous emulsion or aqueous dispersion of the silicone rubber composition, it has an extremely small particle size.

Abstract: Disclosed are novel, cross-linked or cross-linkable linear poly(organohydrosiloxanes) wherein the cross-linking units are derived from polycyclic polyenes. These polymers or prepolymers are prepared by reacting or partially reacting the poly(organohydrosiloxanes) with the polycyclic polyene in the presence of a catalyst.

Abstract: A gasket of a nonwoven sheet material, and a coating composition on at least one side of the nonwoven sheet material. The coating composition is a reaction product of a vinyl functional polydimethylsiloxane, a trimethylsiloxy silica terpolymer, a reactive diluent, and a catalyst. The reactive diluent can be a methyl vinyl cyclic siloxane having the formula (MeViSiO).sub.n wherein n is an integer of from three to five, Me is methyl, and Vi is vinyl.

Abstract: Thermoplastic compositions and composites are produced which have fewer and smaller voids with more consistent dimensions compared to conventional unreinforced and fiber reinforced thermoplastics. The high modulus thermoplastic contains silicone semi-interpenetrating polymer networks which are formed by vulcanization within the thermoplastic and initiated during melt processing. Parts molded from the compositions are more homogeneous, with evenly distributed voids, thus reducing the possibility of strss fractures. The compositions are particularly useful in the molding in thick cross-section and variable thickness parts and have been found to have increased thermal stability.

Abstract: A composition for forming a release coating comprises:(A) 100 parts by weight of a polyorganoborosiloxane having an average composition represented by formula I:R.sub.a SiO.sub.(4-a)/2 .multidot.(BO.sub.1.5).sub.b (I)wherein R is a substituted or unsubstituted monovalent hydrocarbon group bonded to a silicon atom, a is a number between 1.8 and 2.2, and b is a positive number, and containing at least 30 ppm by weight of boron atoms in the form of .tbd.Si--O--B.dbd. linkages, each molecule thereof containing at least two alkenyl groups bonded to a silicon atom;(B) a polyorganohydrogensiloxane containing in each molecule at least three hydrogen atoms bonded to silicon atoms in an amount of 0.5 to 10 hydrogen atoms for each of the alkenyl groups in component (A); and(C) a catalytic amount of a curing catalyst selected from the group consisting of platinum and platinum compounds.

Abstract: High modulus thermoplastic compositions and composites are produced which exhibit enhanced melt integrity and strength, allowing the composites to be melt-drawn to smooth surfaced, high tolerance profiles, such as thin-walled tubing, wire, coatings, films, etc. The melt integrity is improved by adding to the thermoplastic prior to or during thermoplastic melt processing a silicone component which will be vulcanized within the thermoplastic to form a silicone semi-interpenetrating polymer network initiated during the melt processing of the thermoplastic. The composition contains about 0.1 to 20, and preferably about 1 to 4 weight percent of the silicone network, and may also contain fibrous reinforcement and/or filler/modifiers.

Abstract: Addition curable silicone release compositions comprised of a vinyl-functional base polymer, a cross-linking agent, a precious metal catalyst, and an effective amount of C.sub.4 -C.sub.30 .alpha.-olefins are provided which allow reduction in the amount of catalyst or allow the use of vinyl-containing polymers having a lower degree of functionality. The compatibility of the .alpha.-olefin additives allow the preparation of a wide range of serviceable release coating compositions at reduced cost and improved efficiency.

Abstract: The liquid silicone rubber compositions of this invention comprise an organopolysiloxane having silicon-bonded alkenyl radicals, a reinforcing silica filler and, as the curing catalyst, a platinum-alkenylsiloxane complex wherein the pK.sub.a value of the catalyst when measured under a specifed set of conditions is from 2.0 to 9.0, inclusive. The compositions have an excellent storage stability as one part of a two-package liquid silicone rubber composition that cures by a platinum catalyzed hydrosilation reaction.

Abstract: Polyorganosiloxane compositions comprising:(A) a polyorganosiloxane having two or more of the following unit, in the molecule, represented by the formula: ##EQU1## wherein, R.sup.1 represents an alkenyl radical; R.sup.2 represents a substituted or unsubstituted monovalent hydrocarbon radical having no unsaturated aliphatic bond; a is an integer of 1 of 2; b is an integer of 0 to 2; and a+b is an integer of 1 to 3;(B) a polyorganohydrogensiloxane, having units represented by the formula: ##EQU2## wherein, R.sup.3 represents a substituted or unsubstituted monovalent hydrocarbon radical; c is an integer of 0 to 2; d is an integer of 1 or 2; and c+d is an integer of 1 to 3,and having at least three hydrogen atoms bonded to silicon atoms in a molecule, in an amount such that the number of the hydrogen atoms bonded to silicon atoms may be 0.5 to 4.0 per R.sup.

Abstract: Compositions yielding optically clear silicone elastomers are obtained by preparing a homogeneous mixture comprising a liquid polydiorganosiloxane containing at least two vinyl or other ethylenically unsaturated radicals per molecule and a finely divided silica filler treated with a hexaorganodisilazane and then adding additional hexaorganodisilazane in an amount equal to at least 5 percent of filler weight. The blending is preferably carried out using a high rate of shear and volatile materials are removed by heating the composition under reduced pressure.

Abstract: The water-repellent silicone water-based emulsion composition of the present invention consists of a mixture of (A) a silicone water-based emulsion composed of water, emulsifying agent, and diorganopolysiloxane having at least 2 silicone-bonded hydroxyl groups in each molecule, (B) a silicone water-based emulsion composed of water, emulsifying agent, and organohydrogenpolysiloxane having at least 2 silicon-bonded hydrogen atoms in each molecule, and (C) curing catalyst. It is characterized by an excellent storage stability, and by the formation on curing of a rubbery elastomeric coating film which has an excellent alkali resistance, water repellency, water-repellant sealability, and durability of adhesion.

Abstract: The water permeability of cured thermosetting organic resin compositions is reduced and the dimensional stability of these compositions during molding is improved by the addition to the curable resin composition of a finely divided, cured organosiloxane material prepared from a curable organopolysiloxane, a curing agent for the organopolysiloxane, an optional silica filler and an aromatic hydrocarbon compound containing a substituted benzene ring where the substituent is a monovalent ethylenically unsaturated hydrocarbon radical or an alkenyloxy radical.

Abstract: A silicone rubber stock, giving an elastomer upon cure by hot air-vulcanization which has a low compression set, is obtained when a silicon composition containing at least two .tbd.SiH groups is added to a silicone rubber base which contains a polydiorganosiloxane gum having at least two alkenyl groups per molecule.

Abstract: A curable mixture for preparing soft silicone elastomers having low exudation properties comprises:(a) 100 parts by weight of a vinyl-containing base polymer of the formula ##STR1## in which R and R' are alkyl having 1 to 8 carbon atoms, aryl having 3 to 8 carbon atoms, vinyl having 3 to 8 carbon atoms, and fluoroalkyl having 3 to 8 carbon atoms, with the proviso that said base polymer contains a statistical average of 0.5 to 1.8 vinyl groups per molecule, andx is a sufficiently large number that the viscosity of the polymer is between 0.1 and 300,000 Pascal-seconds at 20.degree. C.,(b) 0.1 to 50 parts by weight of an organohydrogensiloxane of the formula ##STR2## wherein R" is an alkyl having 1 to 8 carbon atoms, aryl having 3 to 8 carbon atoms or fluoralkyl having 3 to 8 carbon atoms,m is at least 3, and the sum of n and m is a sufficiently large number that said siloxane has a viscosity of 0.005 to 0.1 Pascal-seconds at 25.degree. C.

Abstract: An aqueous silicone emulsion coating material has been developed with can be used to form a membrane with a decorative, uneven surface. The decorative surface is durable and waterproof. The coating material consists essentially of aqueous silicone emulsion which gives an elastomer upon removal of the water component, inorganic filler, and short, hydrophilic, organic fibers.