Abstract: A method of polymerizing an oligomer comprising a polydiorganosiloxane, polydiorganocyclosiloxane, or mixture thereof in the presence of reinforcing filler using a catalytic amount of sulfuric or sulfonic acid is described. The sulfonic acid is of the formula XSO.sub.3 H wherein X is selected from the group consisting of halogen, alkyl, aryl, alkoxy, and alkaryl radicals. The dispersion of reinforcing filler in polydiorganosiloxane is produced using less energy, with fewer manufacturing steps than current commerical processes. The silicone polymer-filler mixture produced by this method is useful as electrical insulation compounds, in greases, and in producing curable compositions useful as sealants, caulking compounds, and heat curable silicone elastomeric compositions.

Abstract: Oligomers of low molecular weight polydiorganosiloxanes, polydiorganocyclosiloxanes, or mixtures are polymerized in the presence of acidic or neutral reinforcing fillers. Trifluoromethane sulfonic acid is used as the polymerization catalyst. The method can also include endblocked polydiorganosiloxane to control the molecular weight of the silicone polymer in the silicone polymer-filler produced. The method combines the oligomer and filler, heats to from about 70.degree. to 150.degree. C., adds catalyst, adjusts temperature, and polymerizes the mixture, then inactivates with a Lewis base such as calcined magnesium oxide. The non-crepeing silicone polymer-filler mixture which is the product of the method is usable as electrical insulation grease, or as a reinforced polymer mixture useful in producing silicone elastomers. The mixture can be mixed with curing agents to produce heat curable and moisture curable elastomeric compositions.

Abstract: A method of producing a silicone polymer-filler mixture in powder form has been developed. The method combines an oligomer consisting of a polydiorganosiloxane, sufficient acidic or neutral reinforcing filler to yield a powder, and a catalytic amount of a catalyst consisting of (a) sulfuric acid or a sulfonic acid of the formula XSO.sub.3 H wherein X is selected from the group consisting of halogen, alkyl, aryl, alkoxy and alkaryl radicals, (b) perfluorinated alkane sulfonic acid, and (c) a combination of quaternary ammonium carboxylate and carboxylic acid, to give a powdery mixture. The powdery mixture is polymerized, then the catalyst is inactivated while maintaining a powdery state. The method requires a minimum of energy for mixing.

Abstract: Polyacetals and polyketals are prepared by reacting emulsified carbonyl compounds with emulsified polyfunctional alcohols in aqueous media and in the presence of specified polycondensation catalysts. Coherent films of the resultant polymers can be applied to substrates from aqueous or non-aqueous media.

Abstract: Polyesters are prepared by reacting aqueous compositions containing an emulsified hydroxyacid or an emulsified mixture comprising a polyfunctional carboxylic acid or anhydride and a polyfunctional alcohol. The emulsion also contains a suitable polycondensation catalyst. The resultant polyesters are useful as plasticizers and as precursors for alkyd resins and other polymers.

Abstract: An aqueous silicone emulsion is described which provides an elastomeric product upon removal of the water under ambient conditions. The emulsion comprises a continuous water phase and a dispersed phase of crosslinked silicone. The silicone phase is the product of radical produced crosslinking of hydroxyl endblocked polydiorganosiloxane. The polydiorganosiloxane is crosslinked after it has been dispersed in water. Preferred polydiorganosiloxanes contain vinyl-substituted siloxane units and can be crosslinked by high energy radiation or the combined action of heat and an organic peroxide.

Abstract: An aqueous silicone emulsion is described which provides an elastomeric product upon removal of the water under ambient conditions. The emulsion comprises a continuous water phase and an anionically stabilized dispersed silicone phase which is a graft copolymer of a hydroxyl endblocked polydiorganosiloxane and an alkali metal silicate. The emulsion is formed and maintained in a stable condition by control of the pH within the range of 8.5 to 12 inclusive. In the method of preparing the emulsion, an organic tin compound can be employed to accelerate the formation of the graft copolymer.

Abstract: A silicone emulsion having a dispersed phase of an anionically stabilized hydroxylated polydiorganosiloxane and a colloidal silica and a continuous phase of water in which the pH is 9 to 11.5 provides an elastomeric product, such as a film or coating, upon removal of the water at ambient conditions. The silicone emulsion can be prepared by adding the colloidal silica to the hydroxylated polydiorganosiloxane in an emulsified state and thereafter adjusting the pH within the range of 9 to 11.5 inclusive with such materials as an organic amine or sodium hydroxide. These emulsions are stable during storage over extended periods of time and will provide elastomeric products. A silicone emulsion can also be prepared as described except the pH is adjusted above 11.5.

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: The impact strength of certain thermoplastic vinylic polymers is improved by polymerizing the corresponding monomers in an emulsion of a diorganosiloxane containing units of the formula HSR'SiR.sub.n O.sub.3-n/2. For example a styrene acrylonitrile copolymer containing 20 percent by weight of a dimethylsiloxane-3-mercaptopropylsiloxane copolymer having 1 mol percent mercaptosiloxane has an Izod notched impact strength of 10.8 foot pounds per inch.

Abstract: Improvement in impact strength of certain vinylic polymers is obtained by dissolving a mercaptosiloxane-dimethylsiloxane copolymer in a vinylic monomer and converting the monomer to a polymer by bulk or suspension polymerization in the presence of a free radical generator. For example, a copolymer of mercaptopropylmethylsiloxane and dimethylsiloxane is dissolved in styrene and the styrene is copolymerized with acrylonitrile in bulk and/or in water suspension using benzoyl peroxide as a catalyst.

Abstract: The impact strength of certain thermoplastic vinylic polymers is improved by polymerizing the corresponding monomers in an emulsion of a diorganosiloxane containing units of the formula HSR'SiR.sub.n O.sub.3--n/2. For example a styrene acrylonitrile copolymer containing 20 percent by weight of a dimethylsiloxane-3-mercaptopropylsiloxane copolymer having 1 mol percent mercaptosiloxane has an Izod notched impact strength of 10.8 foot pounds per inch.