Abstract: Solid substrates are provided with a cured silicone release coating by applying certain mercaptoalkyl-containing triorganosiloxane-endblocked polydiorganosiloxane fluids to the surface of the substrate and exposing the applied fluid to energetic radiation to rapidly cure and bond the fluid. For example, a mixture of benzophenone and a trimethylsiloxane-endblocked copolymer of dimethylsiloxane units and methylmercaptopropylsiloxane units, when applied to kraft paper and cured with ultraviolet light, provides premium release of aggressive acrylic adhesive from the surface of the coated paper.

Abstract: A light-fugitive dye is added to silicon-containing priming compositions to aid in the application of the priming compositions to a surface and to aid in the application of silicon-containing coating compositions over the primed surface before becoming colorless in the presence of light.

Abstract: Aqueous, acidic compositions are disclosed which consist essentially of polydimethylsiloxane, water, an acid, an abrasive and colloidal silica flocculated with a non-ionic surfactant. The compositions are especially useful for cleaning and conditioning smooth siliceous surfaces such as the surfaces of glass-ceramic cooking utensils and appliances.

Abstract: Endblocked methylpolysiloxane fluids, such as trimethylsiloxane-endblocked polydimethylsiloxanes, are made more resistant to thermally induced siloxane rearrangement by incorporating therein certain amounts of titanium-, zirconium-, or hafnium-containing compounds. Incorporation of these compounds may be accomplished either by mixing organosiloxy derivatives of Ti, Zr, or Hf with the fluid or by mixing certain organic derivatives of Ti, Zr, or Hf with the fluid and heating the mixture to decompose the added organic derivative. Furthermore, incorporation may be accomplished either by mixing the correct amount of the Ti, Zr, or Hf compound with the fluid or by mixing an excessive amount of the Ti, Zr, or Hf compound with the fluid to form a thermal-stability additive which may be diluted with additional fluid to achieve the correct amount of Ti, Zr, or Hf compound.

Abstract: Stable emulsions of a polar liquid in a non-polar base liquid are prepared with the cooperating action of a mixture of a water-in-oil surfactant having an HLB value of from 2 to 10 and certain polydiorganosiloxane-polyoxyalkylene copolymers. An emulsion of interest is an anti-perspirant composition comprising an aqueous solution of aluminum chlorhydrate as the polar liquid dispersed in cyclopolydimethylsiloxanes as the non-polar base liquid, using a mixture of nonylphenoxy polyethoxyethanol and a copolymer of a trimethylsiloxane-endblocked polydimethylsiloxane containing a minor amount of methylhydrogensiloxane units and an allyloxy-endblocked polyoxyethylenepolyoxypropylene copolymer.

Abstract: Radiation-curable compositions consisting essentially of a triorganosiloxane-endblocked polydiorganosiloxane fluid bearing a small percentage of mercaptoalkyl radicals and a curing agent comprising a 1,1'-oxy-bis-(1-methyl-1-silacyclopentene) are disclosed. When applied to a substrate and exposed to energetic radiation these compositions rapidly cured to provide a coating on the substrate that releases aggressive adhesives. Advantageously, the coating, when cured with ultraviolet light in air, is essentially free of the obnoxious odor which characterizes the analogous compositions of the art which are cured with only polymethylvinylsiloxane as a curing agent.

Abstract: Block copolymers are prepared by coupling a poly-.alpha.-methylstyrene block with a polydiorganosiloxane block through a small amount of coupling units of the formula ##STR1## where R denotes an alkyl radical of 1 to 4 carbon atoms. The resulting block copolymers have an improved glass transition temperature, reaching a value of approximately the glass transition temperature of an analogous poly-.alpha.-methylstyrene when R is tertiary-butyl.

Abstract: When a small amount of polytetrafluoroethylene powder is mixed with certain curable polydiorganosiloxane compositions containing a reinforcing silica and an organic peroxide curing agent and the resulting mixture is extruded and heat-cured, the resulting elastomeric article has a durometer of less than 30 and has a greatly reduced amount of porosity or bubbles.

Abstract: Methylsilacyclopentenyl-containing amides and lactams, such as methylsilacyclopentenyl-N-methylacetamide and methylsilacyclopentenyl-epsilon-caprolactam are disclosed. These compounds display unexpected silylating ability when mixed with an active-hydrogen-containing compound. In particular, organic and organosilicon compounds having at least one --OH, --SH, ##STR1## or --NH.sub.2 group are readily converted to a methylsilacyclopentenyl derivative.

Abstract: Fluorocarbon siloxanes of the formula ##STR1## ARE DISCLOSED. Their use as reversion resistant curing agents in curable compositions comprising reversion resistant siloxanes of the formula ##STR2## are also disclosed.

Abstract: Organosilicon compounds bearing silicon-bonded hydrocarbon radicals and silicon-bonded hydrocarbonoxy radicals are obtained by contacting activated silicon, a hydrocarbon ether and a halogen-containing catalyst in a closed system at elevated temperature. Silanes and siloxanes, particularly methylmethoxysilanes, may be prepared and used to prepare valuable silicone materials.

Abstract: The admixing of a small amount of an organosilicon compound containing at least one silicon-bonded hydrogen atom with curable compositions comprising a hydroxyl-containing organosilicon compound, an epoxy compound and certain catalytic aluminum compounds to improve the performance of the cured composition is disclosed. The improved compositions are especially useful as a resin binder in molding compounds that are used to mold electronic devices.

Abstract: Organosilicon compositions comprising at least one silicon-bonded alkenyloxy radical, such as vinyldimethylcarbonoxy, are disclosed. These unsaturated organosilicon compositions are useful as partial or complete replacements for the analogous organosilicon compositions bearing the well-known silicon-bonded vinyl radical. In particular, vinyldimethylcarbinoxy-endblocked polydimethylsiloxane is useful as a component in an elastomeric composition which is cured with an organosilicon hydride.

Abstract: New organosiloxane chelating compositions comprising a siliceous support and an organosiloxane chelating agent bonded to its surface are disclosed. A new method for preparing the composition comprises contacting the siliceous support with a solution of an organosiloxane comprising units of the formula ##STR1## AND OPTIONALLY, UNITS OF THE FORMULA ##STR2## R is --CH.sub.2 COOH or --CH.sub.2 COO.sup.- M.sup.+ ; M.sup.+ is an alkali metal ion, m = 0 or 1, a = 0 or 1, b = 1 or 2, (m.multidot.a) + b is at least 2 and Z is a monovalent hydrocarbon radical having 1 to 6 inclusive carbon atoms.

Abstract: Fluid compositions are disclosed which are useful as coatings on solid substrates. The compositions comprise a mercaptoalkyl-substituted polydiorganosiloxane fluid and a vinyl monomer. The compositions may further comprise a methylvinylpolysiloxane and/or a photosensitizing compound. The compositions, applied and cured on a substrate such as paper, provide improved release of adhesive materials.

Abstract: Fluorocarbon siloxanes of the formula ##STR1## ARE DISCLOSED. Their use as reversion resistant curing agents in curable compositions comprising reversion resistant siloxanes of the formula ##STR2## are also disclosed.

Abstract: Certain polydiorganosiloxane compositions bearing mercaptoalkyl radicals and vinyl radicals are disclosed which cure in the presence of radiation such as ultraviolet light. The compositions consist essentially of a mixture of a triorganosiloxane-endblocked polydiorganosiloxane fluid in which from 1 to 5 percent of the organic radicals are mercaptoalkyl radicals and a methylvinylpolysiloxane. The compositions may be applied to a substrate such as paper and exposed to radiation to prepare a coated substrate that provides premium release of aggressive acrylic adhesives.

Abstract: Compositions comprising certain acrylate-containing polyorganosiloxanes and a hydroperoxy polymerization initiator are anaerobically curing sealant compositions. For example, a composition comprising a polyorganosiloxane consisting essentially of 42 mole percent trimethylsiloxane units and 58 mole percent methacryloxypropyl silsesquioxane units and cumene hydroperoxide remained uncured for several days in the presence of oxygen but cured to a solid, insoluble sealant when placed on the threads of an iron bolt and a nut was threaded onto the bolt.

Abstract: Heat-curable elastomeric compositions having unprimed adhesion to a substrate are obtained by mixing from 0.1 to 10.0 parts by weight of a room-temperature-curable silicone elastomer stock having silicon-bonded acetoxy radicals with 100 parts by weight of an organic-peroxide-curable silicone rubber.

Abstract: Organopolysiloxane compositions suitable for use in a liquid injection molding process of elastomeric articles are produced by mixing a vinyl-endblocked polydiorganosiloxane fluid copolymer containing dimethylsiloxane units and methyl-3,3,3-trifluoropropylsiloxane units, a treated, reinforcing silica filler, a platinum-containing catalyst, a curing agent comprising dimethylhydrogensiloxane units as the only source of silicon-bonded hydrogen atoms and, as an inhibitor for the platinum-containing catalyst, certain olefinic siloxanes and/or acetylenic siloxanes. These compositions are especially suited for liquid injection molding because they can be stored at room temperature for days and can be injected into a hot mold with pressures less than 352 kg./sq.cm. (5,000 psi) whereon they cure rapidly to an elastomeric article having a tensile strength greater than 42 kg./sq.cm., and elongation at break greater than 300 percent and a tear strength greater than 7 kg./cm.