Abstract: The present invention relates to compounds of the formula ##STR1## in which Z is a halogen atom, a cyano group or a hydroxyl group,n is 0, 1 or 2,R' is a radical of the formulaR'"--[Si(R*).sub.2 ].sub.x (CH.sub.2).sub.y R""-- (9),in whichx is the number 0 or 1,y is an integer from 1 to 18,R'"is a defined in the description,R* is identical or different, optionally substituted C.sub.1 - to C.sub.18 -hydrocarbon or hydrocarbonoxy radicals,R"" is a phenylene or biphenylene radical or a radical of the formula --E--, whereE is a divalent radical of the formula --O-- or --[Si(R*).sub.2 ].sub.z --, andz is the number 0 or 1,and the compounds contain at least one group of the formula --Si(R*).sub.2 -- per molecule, and the radicalR" is a cholesteryl radical, a radical as defined for R* or a radical of the formula --C.sub.6 H.sub.4 --R*,and the preparation and use thereof.

Abstract: A process of producing a methylphenyltrisiloxane having the following general formula: ##STR1## wherein R.sup.1 and R.sup.2 may be the same or different and are each a methyl or phenyl group, the process comprising the step of reacting:(A) methyldiphenylsilanol, with(B) a silazane compound having a diorganosilazane unit having the following formula: ##STR2## wherein R.sup.1 and R.sup.2 are as defined above. According to the process, colorless and odorless methylphenyltrisiloxanes can be obtained easily, safely and economically, without any special deodorizing or decoloring step.

Abstract: The described invention is a process for producing silanes and polysiloxanes. The process comprises contacting silica with a preformed alkylaluminum compound in the presence of a catalyst effective in facilitating the reaction. Preferred catalysts are copper, tin, zinc, phosphorous, and compounds thereof.

Abstract: The instant invention is a one-step process for producing polydiorganosiloxanes (siloxanes). In the described process, a mixture comprising diorganodichlorosilane and a source of triorganosilyl groups is contacted with excess water essentially saturated with hydrogen chloride. Product siloxanes are isolated as well as saturated aqueous hydrogen chloride and anhydrous hydrogen chloride. The amount of triorganosilyl groups present in the mixture is controlled to set the degree of polymerization of product siloxanes. The isolated saturated aqueous hydrogen chloride is recycled to the process. Excess chloride generated in the process is collected as anhydrous hydrogen chloride.

Abstract: Siloxane compounds having the following formula [1]: ##STR1## wherein each R is a substituted or unsubstituted monovalent hydrocarbon group having from 1 to 10 carbon atoms, and n is an integer of from 0 to 100. The compounds are extremely high in reactivity and, therefore, useful as an intermediate or modifying agent in the synthesis of silicone resins and other various organic resins.

Abstract: A diorganopolysiloxane in which a polymerizable functional group is present at one (or both) molecule chain ends and in which an arbitrary group is present at the other end can be easily synthesized. The synthesis involves the opening of a cyclotrisiloxane using an alkali metal silanolate which bears the polymerizable functional group, followed by a capping reaction. The resulting diorganopolysiloxane can be used effectively as a feed material for manufacturing silicone rubbers, feed material for manufacturing novel grafted organopolysiloxanes, comonomer components for resins other than organopolysiloxanes or plastics, etc.

Abstract: Organo(poly)siloxanes having Si-linked, conjugated dienyl groups are prepared by adding a secondary or tertiary acetylenic alcohol (1) to an organo(poly)siloxane (2) having at least one Si-linked hydrogen atom in the presence of a catalyst (3) which promotes the addition of Si-linked hydrogen to an aliphatic multiple bond, and then eliminating water by an intramolecular reaction in the presence of an acid catalyst (4) from the alkenol groups of the organo(poly)siloxane thus obtained.

Abstract: Phenol-organopolysiloxane chainstoppers are phosgenated in combination with a bisphenol to make flame retardant organopolysiloxane-polycarbonate triblock copolymers. The phenol-organopolysiloxane chainstoppers can be made by effecting addition between an aliphatically unsaturated phenol and a silicon-hydride organopolysiloxane.

Abstract: Organosiloxanes (1) of the general formulaR.sup.1.sub.4-n Si(OSiR.sub.3).sub.n,in which R is the same or different and represents a hydrogen atom or a monovalent hydrocarbon radical having from 1 to 18 carbon atom(s) per radical or a substituted monovalent hydrocarbon radical having from 1 to 18 carbon atom(s) per radical, R.sup.1 represents R or a chlorine atom, and n is 3 or 4, are prepared by reacting organodisiloxanes (2) of the general formula(R.sub.3 Si).sub.2 O,with chlorosilanes (3) of the general formulaR.sub.4-n SiCl.sub.n,in which R and n are the same as above, in the presence of phosphonitrile chlorides (4) and cocatalysts (5), in which the cocatalysts (5) are used concomitantly with the phosphonitrile chlorides (4) and are selected from the group consisting of amides of the general formulaX--C(O)--R.sup.2,in which R.sup.

Abstract: A rhodium colloid has been found to be a superior catalyst for the hydrosilylation of silicon hydride having two or three hydrogens attached to silicon. The rhodium colloid is made by effecting reaction between rhodium trichloride and certain silicon hydride.

Abstract: A bisindenyl derivate of the formula I ##STR1## (M.sup.1 =Si or Ge, R.sup.6 and R.sup.7 =unsubstituted or substituted idenyl radical)is obtained in very good yield by reacting a compound of the formula II ##STR2## (X=halogen) with a compound of the formula III or IVR.sup.6 -M.sup.2 (III) R.sup.7 -M.sup.2 (IV)(M.sup.2 =alkali metal)if, in the reaction, compound III or IV is added slowly to compound II.Compound I is suitable as a starting material for the preparation of metallocene catalyst components.

Abstract: The instant invention is a process for reducing residual chloride content of polysiloxane fluids, without detrimental effects on the polysiloxane polymer. The process comprises contacting the polysiloxane fluid, containing residual chloride, with selected weakly-basic alkaline metal compounds at a temperature less than 100.degree. C. After an appropriate contact time, the polysiloxane fluid is separated from the solid alkaline metal compounds. In a preferred embodiment of the present invention, water is added to the process to facilitate removal of residual chloride.

Abstract: A novel organopolysiloxane compound is disclosed which is capable of being cured by crosslinking and exhibiting a liquid-crystalline phase even in a crosslinked condition. The organopolysiloxane has mesogenic groups bonded to the silicon atoms such as --CH.sub.2).sub.3 O--Pn--CO--O--Pn--CN; --CH.sub.2).sub.3 O--CH.sub.2).sub.3 O--Pn--CO--O--Pn--CN; --CH.sub.2).sub.3 O--Pn--CO--O--Pn--F; and --CH.sub.2).sub.3 O--Pn--CO--O--Pn--O--CH.sub.3, in which the symbol Pn denotes a 1,4-phenylene group, and hydrolyzable groups pertaining to the crosslinking reaction.

Abstract: Linear low-molecular-weight organo(poly)siloxanes which are monofunctional or difunctional and in which, if difunctional, the two functionalities are present in siloxane units which are chemically different from each other are prepared by reacting an octaorganocyclotetrasiloxane with lithium silanolate in a molar ratio of 0.9:1 to 1.1:1 in an electron-donating, aprotic solvent at a temperature below 50.degree. C., in the absence of water, and thereafter reacting the resultant lithium siloxanolate thus obtained with an organohalosilane.

Abstract: Alkali-soluble organopolysiloxanes useful in the alkali-developing resist materials for use in microprocesses in LSI device fabrication have the following general formula ##STR1## where A is a hydroxyphenyl group; R is an alkylene group having 1 to 4 carbon atoms; n is zero or one; R.sup.1 is an alkyl group having 1 to 4 carbon atoms; x and z are positive numbers; y is zero or a positive number; x, y, and z have values such that their ratios are 0.3.ltoreq.(x+y)/z.ltoreq.4; and zero.ltoreq.y/x.ltoreq.5.

Abstract: A method is provided for silylating aromatic acylhalide by effecting reaction between an aromatic acylhalide and halogenated polysilane in the presence of an effective amount of a supported transition metal catalyst, such as a transition metal catalyst supported by an organic or inorganic substrate.

Abstract: Polymerizing cyclic trisiloxanes using as the polymerization initiator an alkali metal salt of an organosilane or organopolysiloxane having a terminal alkenyl group, followed by termination of the reaction, produces an organopolysiloxane having an alkenyl group on one end. These organopolysiloxanes are useful for making copolymers and as additives to siloxane elastomers.

Abstract: Polydiorganosiloxanes which have a pendant alkenyl radical in the middle of the molecular chain are prepared by a nonequilibrium, living polymerization of cyclic trisiloxanes using an organopolysiloxane alkali metal salt of the formula ##STR1## where M is lithium, sodium, or potassium, which takes place under substantially anhydrous conditions, and the polymerization is terminated with an end-capping reaction to produce a polydiorganosiloxane of the formula ##STR2## where R.sup.1 is an alkenyl radical. These polymers can be used to make graft copolymers and can be made more functional when the ends are capped with functional groups.

Abstract: Oligomeric siloxanol mixtures containing siloxanolsof the formulaHO--SiR.sub.2 O[SiR.sub.2 O--.sub.n Hand those of the formulaR.sub.3 SiO--[SiR.sub.2 O--.sub.m Hwhere R represents the same or different monovalent hydrocarbon radicals, monovalent halogenated hydrocarbon radicals having from 1 to 18 carbon atoms or hydrogen atoms and n and m are the same or different integers are prepared by hydrolyzing a mixture containing at least one compound of the formula R.sub.3 SiCl and at least one compound of the formula R.sub.2 SiCl.sub.2. These oligomeric siloxanol mixtures can be reacted with the terminal Si-bonded hydroxyl groups of .alpha., .omega.-dihydroxypolyorganosiloxanes.

Abstract: An organopolysiloxane composed of tetrafuctional siloxane units SiO.sub.2 and monofunctional siloxane units R.sub.3 SiO.sub.0.5 can be prepared by reacting an alkyl orthosilicate, e.g., ethyl silicate, or a partial hydrolysis product thereof and an oligomeric organopolysiloxane containing the monofunctional siloxane units in the presence of a catalytic compound which is, different from conventional hydrogen chloride, selected from the group consisting of sulfonic acid group-containing compounds, e.g., sulfuric acid and p-toluene sulfonic acid, and phosphonitrile chloride. In particular, cation exchange resins of sulfonic acid type and fluorinated polysulfonic acid resins can be used as the catalyst in a continuous process in which the reaction mixture is passed through a bed of the catalyst continuously. The inventive method is advantageous over conventional methods because of the absence of the problems of heavy corrosion of the apparatuses and waste disposal due to the hydrogen chloride.

Abstract: A polysiloxane compound modified with two hydroxyl groups at the one end thereof and particularly suitable for improving the surface characteristics of resins prepared by polycondensation of a polyol with another polyfunctional compound, and a silicone-modified polyurethane having superior characteristics such as low frictional properties, water repellency, oil repellency, thrombosis resistance, etc. and also a process for producing the polyurethane are provided, which polysiloxane compound expressed by the formula ##STR1## wherein R represents H, Me (methyl) or Et (ethyl) and n represents an integer of 0 to 4,000, and which silicone-modified polyurethane is obtained from a compound having at least two isocyanate groups and a compound having at least two hydroxyl groups, and by using as a part of the compound having at least two hydroxyl groups, the polysiloxane compound of the above formula (I) in the urethane bond-forming reaction.

Abstract: A continuous process for producing a triorganosilyl end-blocked polydiorganosiloxane fluid with reduced silanol content and reduced branching content is described. The process comprises (a) feeding to a series of two columns packed with an acid-treated clay a liquid siloxane feed mixture, containing as a major portion a polydiorganosiloxane monomer and as a minor portion a triorganosilyl end-blocking material; (b) contacting the liquid siloxane feed mixture with the acid-treated clay in the first and second packed columns, respectively, at a temperature in a range from about 100.degree. to 150.degree. C. at a pressure in a range from about 5 to 1520 mm Hg at a contact time of less than about 15 minutes; (c) separating water vapor from an intermediate mixture between the first and second packed columns; and (d) collecting a product mixture which contains a triorganosilyl end-blocked polydiorganosiloxane fluid with silanol content substantially reduced from the equilibrium mixture.

Abstract: Bisbenzocyclobutene monomers bridged by a polyorganosiloxane group. The monomers are liquid at room temperature.

Abstract: Organopolysiloxanes containing triorganosiloxy terminal units are obtained by a continuous process in which an organopolysiloxane mixture containing organo(poly)siloxanes having triorganosiloxy terminal units and cyclic organopolysiloxanes are introduced into a tube reactor that has been heated to at least 80.degree. C. and which contains a static catalyst bed. The organopolysiloxane composition containing triorganosiloxy terminal units, which exits from the tube reactor is different from the organo(poly)siloxanes containing triorganosiloxy terminal units which were introduced into the reactor. The contents of the reactor in the area between one-third and two-thirds of the distance between the point where the organopolysiloxanes are introduced into the tube reactor and the point where the organopolysiloxanes exit from the reactor, are maintained at a temperature which is at least 50.degree. C. below that which is immediately upstream from the outlet of the reactor.

Abstract: Novel O-silylated ketene acetals and enol ethers are prepared via the 1,4-hydrosilation of a hydrosilation composition selected from the group consisting of aminosilanes, siloxanes and alkylalkoxysilanes with an .alpha.,.beta.-unsaturated carbonyl in the presence of a rhodium catalyst.

Abstract: An improvement is provided in the compression molding of lignocellulosic composite articles, such as particle or flake board, in which polyisocyanate binder systems are employed, the improvement being the provision of a novel functional polysiloxane-hydroxyle substituted mono-carboxylic acid or metal salt-isocyanate terpolymer as a release agent on the mold surface or surfaces to give multiple release. Optionally, organopolysiloxane fluids may be employed along with the terpolymer release agent as a diluent.

Abstract: Pressure sensitive adhesives can be protected with a releasable liner having a cured fluoroalkyl silicone coating which contains as little as two percent fluoroalkyl-substituted siloxane units. In a preferred embodiment of this invention silicone pressure sensitive adhesives can be solvent-cast, and even cured, directly onto the release surface of the liner and can be removed from the protective liner with a force of no more than 400 grams per inch. The fluoroalkyl silicone copolymers of this invention are prepared by a process which involves the preparation of a cohydrolyzate of fluoroalkyl-containing and fluoroalkyl-free siloxane units, followed by further polymerization of the cohydrolyzate with other siloxane units.

Abstract: A process having the characteristic that a silicon compound having at least one hydrogen atom directly bonded to silicon in each molecule is addition reacted with an organic compound having at least one aliphatic double bond in each molecule in the presence of a platinum catalyst and an amide compound with the formula, RCONR.sup.1 R.sup.2. The presence of the amide maximizes the yield of the desired beta-adduct and minimizes the yield of the alpha-adduct.

Abstract: An efficient method is proposed for the preparation of an organosiloxane oligomer represented by the general formula YSi(R.sup.1).sub.n (--O--SiR.sub.3).sub.3-n, in which each of the groups denoted by R and R.sup.1 is a halogen-substituted or unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms, Y is a hydrogen atom or a monovalent group selected from methyl, phenyl, vinyl, chloromethyl and 3-(meth)acryloxypropyl groups and n is zero, 1 or 2, by the reaction of an organosilicon halomagnesium salt of the formula R.sub.3 Si--O--MgX, in which X is a halogen atom, and an organosilane compound of the general formula YSi(R.sup.1).sub.n (Z).sub.3-n, in which Z is a halogen atom or a lower alkoxy group. In particular, tetrasiloxane compounds represented by the general formula Y.sup.1 Si[--O--Si(CH.sub.3).sub.2 (CH.sub.2 CH.sub.2 CF.sub.3)].sub.3, in which Y.sup.1 is a hydrogen atom, chloromethyl group or 3-methacryloxypropyl group, are each a novel compound not known in the prior art.

Abstract: A method is provided for silylating organic substrates, utilizing a halogenated polysilane, such as 1,1,2,2-tetrachloro dimethyldisilane and an aromatic acyl halide, for example, trimellitic anhydride acid chloride in the presence of a transition metal catalyst.

Abstract: The method of dripping an alkyl silicate into a mixture of an aqueous hydrochloric acid which contains at least 5 weight percent hydrogen chloride and a trialkylsilane or a disiloxane at a temperature of from 0.degree. to 90.degree. C. is a highly reproducible method for producing a three-dimensional structure of monofunctional siloxane units and tetrafunctional siloxane units. The organosilicon polymers produced are useful as tack agents, coating agents, and as additives in other compositions.

Abstract: In the alkenyl-containing diorganopolysiloxane of the invention, the distribution of the alkenyl groups in the molecule is not random as in conventional alkenyl-containing diorganopolysiloxanes but each of at least three siloxane units linked to each of the terminal silicon atoms has an alkenyl, e.g. vinyl, group while at least six of the uninterruptedly linked siloxane units excepting the above mentioned alkenyl-containing units adjacent to the molecular chain ends are free from aliphatic unsaturation. A method for the preparation of the diorganopolysiloxane having the alkenyl groups in such a localized distribution is disclosed. When the diorganopolysiloxane is used as the principal ingredient of a curable organopolysiloxane composition as combined with a crosslinking agent, the composition, despite its relatively low viscosity, can give a cured rubber having markedly improved mechanical strengths.

Abstract: A colloidal hydrosilylation catalyst is provided by effecting reaction between a silicon hydride or a siloxane hydride and a Pt(O) or Pt(II) catalyst. The colloidal catalyst forms stable mixtures with olefinically unsaturated organopolysiloxanes.

Abstract: A method for purifying silicone oil used particularly as a cooling and/or insulation agent in electrical high voltage devices. The silicone oil is purified by the addition of drying agents, e.g. molecular sieves, and adsorption agents, e.g. activated carbon, and by mechanically moving the mixture. After subsequent sedimentation, filtration and degasification, purified silicone oil is obtained which can again be used as a coolant and/or insulating agent.

Abstract: Organopolysiloxanes of the formula ##STR1## in which R is an alkyl radical having 6 to 18 C atoms,R' is an alkyl radical having 1 to 7 C atoms or the phenyl radical,a and b each independently is an integer from 1 to 500, the ratio of b:a being at least 2, are miscible with mineral oil and synthetic lubricating oils and have a pour point below -15.degree. C.

Abstract: A method for hydrogenating olefins and alkynes is provided wherein the unsaturated hydrocarbon is reacted under mild conditions in the presence of a cyclometallated transition metal catalyst which shows greater resistance to degradation caused by oxidation.

Abstract: New organosilicon compounds of the formula ##STR1## R represents a hydrogen radical with 1 to 6 carbon atoms, or a phenyl radical;R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are the same or different and represent hydrogen or methyl radicals;R.sup.5, R.sup.6, R.sup.7 and R.sup.8 are the same or different and represent hydrogen, fluorine or hydrocarbon radicals with 1 to 8 carbon atoms, or fluorinated hydrocarbon radicals, in which at least one R.sup.5, R.sup.6 R.sup.7 or R.sup.8 radicals must be a fluorine or a fluorinated hydrocarbon radical;Y is a hydrolyzable radical, hydroxyl radical or organosiloxanyl radical;A represents ##STR2## in which R.sup.9 may be the same or different and represents a hydrogen or a methyl radical; anda has a value of 0, 1, 2, or 3.

Abstract: A random siloxane copolymer composition, and a process for using the composition in a hydraulic brake system of a vehicle, is described. The random copolymer consists essentially of alkylmethylsiloxane and dimethylsiloxane units, wherein said alkyl group contains from five to ten carbon atoms, and the viscosity of said fluid is 15-50 cS at 25.degree. C. Within a relatively narrow compositional range, these fluids dissolve at least 15% less air than comparable polydimethylsiloxane fluids. Moreover, the copolymer may be readily formulated into brake fluid compositions which meet Department of Transportation (DOT 5) and, in the case of preferred compositions, Military (MIL-B-46176) specifications. The potential benefit of reduced air solubility is an improved margin of safety under harsh driving conditions.

Abstract: A mixture of an organopolysiloxane fluid, a zirconium-containing organosiloxane compound having at least one zirconium atom and at least one siloxane unit, and a cerium-containing organosiloxane compound having at least one cerium atom and at least one siloxane unit is an organopolysiloxane viscous coupler fluid which can be used in gear systems. These coupler fluids undergo little viscosity increase or decrease and little torque variation at elevated temperature and under high shear over long periods of time.

Abstract: Multifunctional organopolysiloxane resin systems are provided whose starting materials comprise a reactive vinyl containing silane, a disubstituted silane and a trisubstituted silane hydrolyzed together to form a resin system. The preferred material of the resin system has a viscosity of from 7 to 70 centistokes at 25.degree. C. The preferred material is in the form of a contact lens and also contains an ester and a hydrophilic agent.

Abstract: A xylene-soluble, resinous copolymer containing SiO.sub.2 units, trimethylsiloxane units, and alkenyldimethylsiloxane units such as 5-hexenyldimethylsiloxane units is disclosed. The resinous copolymer is useful as a component in silicone coatings, especially silicone release coatings, to provide intermediate range release forces against adhesives. The higher alkenyl functionality provides faster reaction with other coating components and reduced odor during cure of UV curable mercaptosilicone compositions.

Abstract: A method is provided for hydrolyzing chlorosilanes, for example, dimethyldichlorosilane, to produce dimethylpolysiloxane hydrolyzate and an aqueous solution of hydrogen chloride along with anhydrous hydrogen chloride. Chlorosilane hydrolysis is effected in the presence of a substantially stoichiometric equivalence of water which results in the direct generation of anhydrous hydrogen chloride and a saturated aqueous hydrogen chloride solution. The saturated aqueous solution of hydrogen chloride can be recycled to the chlorosilane hydrolysis step.

Abstract: A process is disclosed for the direct synthesis of cyclic and oligomeric organosiloxanes, such as dimethylsiloxanes, comprising reacting a hydrocarbon ether and a hydrocarbon halide with a fluidized or agitated bed of activated silicon particles with a maximum contact time of five minutes, and continuously withdrawing products from that reaction.

Abstract: Compounds of the formula ##STR1## whereby, in the average molecule, 20 to 100% of the R.sup.1 radicals are ##STR2## in which R.sup.2 is an alkylphenyl, dialkylphenyl or trialkylphenyl radical and the sum of the alkyl carbon atom per phenyl radical is 6 to 12, a=1 to 2; and0 to 80% of the R.sup.1 radicals are ##STR3## in which R.sup.3 is an alkyl radical with 1 to 16 carbon atoms, an organoacyl radical with 1 to 12 carbon atoms, or an aryl radical, b=1 to 2, c=1 to 30, andn=3 to 30, as well as melt spinning finishes comprising5 to 100 weight percent of the compounds of claim 1,0 to 90 weight percent of nonpolar or weakly polar oils,0 to 30 weight percent of nonionic surfactants,0 to 15 weight percent of ionic surfactants,and optional conventional additives, the sum of the components being 100 weight percent.

Abstract: Phenyl-containing organopolysiloxane fluids characterized by the formula, ##STR1## wherein Ph is phenyl, R is hydrogen, trimethylsilyl or mixtures thereof and wherein x and y have a value sufficient to provide a phenyl content of from about 7 weight percent to about 80 weight percent are provided. Also provided are polycarbonate compositions comprising these novel phenyl containing organopolysiloxane fluids.

Abstract: In a process for producing rigid polyurethane foams, polysiloxane-polyoxyalkylene block copolymers having the formula ##STR1## are used, in which A represents polyoxyalkylene blocks A.sup.1 or A.sup.2 having the formula --R.sup.2 --O--(C.sub.m H.sub.2m O).sub.y R.sup.1, which are linked to silicon by an SiC bond and in which R.sup.1 represents a hydrogen atom or an alkyl radical with 1 to 4 carbon atoms, R.sup.2 represents a bridging group, y is a whole number, and m has a value of 2.0 to 2.6, with the proviso that:a. the A.sup.1 blocks comprise 70 to 100 weight percent oxyethylene units, the remainder being oxypropylene units, and have a molecular weight from about 250 to 1,000,b. the A.sup.2 blocks comprise 35 to 65 weight percent oxyethylene units, the remainder being oxypropylene units, and have a molecular weight from about 600 to 1,500,c. the molar ratio of the A.sup.1 block to the A.sup.2 blocks is 85:15 to 15:85 and there is at least one block of A.sup.1 and block of A.sup.

Abstract: A binder system is provided for the preparation of lignocellulosic composite molded articles, such as flake or particle board, which incorporates an internal release agent and comprises an emulsifiable organic di- or polyisocyanate and an emulsifiable carboxy functional siloxane. The emulsifiable carboxy functional siloxane is preblended with the di- or polyisocyanate providing for increased mold release properties.

Abstract: Asymmetrical disiloxanes are prepared by reacting (a) a silane containing three SiC-bonded monovalent organic radicals in which at least one may be substituted with Si-bonded hydrogen and an SiOC-bonded monovalent organic radical with (b) a symmetrical disiloxane which is different from the disiloxane obtained from the hydrolysis of silane (a), and contains at least two identical substituents in the presence of water and an acid at a temperature of from -10.degree. to about 50.degree. C.

Abstract: The room temperature curable organopolysiloxane composition of the invention comprises a dimethylpolysiloxane terminated at both molecular chain ends with silanolic hydroxy groups, an organocyclopolysiloxane, typically a cyclotetrasiloxane, having 2 or more alkenyloxy groups such as isopropenyloxy groups in a molecule as a crosslinking agent for the dimethylpolysiloxane and a guanidyl-containing organosilane or polysiloxane compound as a curing catalyst. The composition is capable of giving a cured rubbery elastomer when kept in a moisture-containing atmosphere at room temperature without the problems in the prior art compositions such as noxious condensation products or poor adhesion to the surface of the substrate on which the composition has been cured.

Abstract: [2-(p-t-Butylphenyl)ethyl]silanes are provided having the general formula:Si(B).sub.x (R).sub.y (A).sub.zwherein B is a (p-t-butylphenyl)ethyl moiety, R is an alkyl or aryl moiety and A is a hydrolyzeable moiety; x equals 1 or 2, y equals 0, 1 or 2 and z equals 1, 2 or 3 such that x plus y plus z equals 4. The bulky substituted silanes are produced by the hydrosilylation of p-t-butylstyrene.[2-(p-t-Butylphenyl)ethyl] substituted disiloxanes are also provided, having the general formula:(B).sub.x (R).sub.y (A).sub.z Si--O--Si(A).sub.z (R).sub.y (B).sub.xwherein B, R, A, x, y and z are as defined above except that z equals 0,1 or 2 and x plus y plus z equals 3. The bulky substituted disiloxanes are produced by the hydrolysis of above-described bulky substituted silanes.