Abstract: The present invention is a process for converting chlorine end-terminated polyorganosiloxanes to polyorganocyclosiloxanes. The process comprises forming a mixture comprising chlorine end-terminated polyorganosiloxanes, aqueous hydrogen chloride, and a heterogeneous reequilibrium catalyst. The mixture is heated at a temperature within a range of about 70.degree. C. to 150.degree. C. to effect reequilibrium of the chlorine end-terminated polyorganosiloxanes to form polyorganocyclosiloxanes which are removed from the process as they are formed.

Abstract: The present invention relates to cyclic siloxanes which have at least one group of formula (1) bonded to a silicon atom--(CH.sub.2).sub.x --R"--[--L--A--].sub.y --(L).sub.z --T (1),in which x is an integer having a value of at least 2, preferably having a value of from 2 to 10, R" is a chemical bond or a divalent radical of the formula --COO--, --OOC--, --CH.sub.2 --CH.sub.2 --, --CH.dbd.CH--, --C.tbd.C--, --N.dbd.N--, --N.dbd.N(O)--, --CH.dbd.N--, --N.dbd.CH--, --N.dbd.N--, --N.dbd.N(O)--, --N.dbd.CH--, --CH.dbd.N--, or --Si(R).sub.

Abstract: A process for preparing cyclosiloxanes by the redistribution of a cyclosiloxane or mixture of cyclosiloxanes in the presence of a rearrangement catalyst.

Abstract: A method for hydrolyzing an organochlorosilane to produce an organopolysiloxane, which comprisesa first-stage hydrolysis of hydrolyzing the organochlorosilane using a substantially stoichiometrically equivalent amount of water, thereby producing a hydrolyzate, anda second-stage hydrolysis of hydrolyzing the hydrolyzate obtained in the first-state hydrolysis using a stoichiometrically excess amount of aqueous hydrogen chloride solution having a predetermined hydrogen chloride concentration, thereby to produce an organopolysiloxane as a hydrolyzate and, at the same time, regulate the viscosity of the organopolysiloxane.

Abstract: Organic polymer additive containing polar functional groups enhances the stability of palladium-containing catalysts for the telomerization of conjugated diolefins in the presence of active hydrogen-containing telomerization agent to produce alpha-substituted alkadienes.

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: 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: 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: The present invention relates to a process for the preparation of alkoxy, aryloxy, alkyl, and aryl cyclotetrasiloxanes from a metal silicate halide salt, Ca.sub.8 Si.sub.4 O.sub.12 Cl.sub.8.

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: Admixtures of cyclic and linear diorganopolysiloxanes, relatively rich in cyclic species, are produced by hydrolyzing a diorganodichlorosilane, in an aqueous hydrochloric acid medium, in the presence of an effective amount of at least one amphoteric surface-active agent, characteristically at least one compound of the formula: ##STR1## The medium of hydrolysis is facilely separated into an aqueous phase and a cyclic oligomer-enriched siloxane phase essentially devoid of surfactant(s).

Abstract: What is disclosed is a process for converting polydiorganosiloxanes to cyclopolydiorganosiloxanes with reduced cleavage of organic groups from silicon atoms. The process comprises (A) feeding a mixture of the polydiorganosiloxanes, a catalyst, and an organic solvent to a device in which water is formed as the polydiorganosiloxanes react in the presence of the catalyst and the organic solvent, the water formed being driven out of said device as a two-phase organic solvent/water azeotrope; (B) reacting the polydiorganosiloxane/catalyst/organic solvent mixture from (A), essentially free of water, to convert the polydiorganosiloxanes to the desired product cyclopolydiorganosiloxanes; and (C) recovery of the desired product cyclopolydiorganosiloxanes.

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: Disclosed is a process for the performance of organic reactions in the liquid phase wherein silicone oils are used as the reaction medium. These silicone oils have no functional groups, are liquid at room temperature and have viscosities between 40 and 20,000 cs. at 25.degree. C. The obtained reaction products are very pure and generally do not require additional purifying operations.

Abstract: The invention discloses a novel cyclic organopolysiloxane compound having one or more of 3,3,3-trifluoropropyl groups and one or more of alkenyloxy groups, e.g. isopropenyloxy group of the formula --O--C(CH.sub.3).dbd.CH.sub.2, each directly bonded to the silicon atom in a molecule. This novel organopolysiloxane compound is useful as a crosslinking agent for a hydroxy-terminated diorganopolysiloxane and a formulation of a room temperature curable organopolysiloxane composition capable of giving a rubbery elastomer by curing is proposed comprising, each in a limited proportion, (a) a hydroxy-terminated diorganopolysiloxane, (b) the above disclosed novel cyclic organopolysiloxane having 2 or 3 alkenyloxy groups, (c) a second cyclic organopolysiloxane having 2 or 3 alkenyloxy groups each directly bonded to the silicon atom in a molecule and (d) a guanidino-containing organosilicon compound, e.g. 3-(tetramethylguanidino)propyl trimethyl silane, as a curing accelerator.

Abstract: This invention relates to a process for the preparation of polysiloxanes by reacting halosilanes in the presence of metal oxides and sulfolane. Preferred metal oxides include antimony (III) oxide, antimony (V) oxide, cadmium oxide, calcium oxide, copper (II) oxide, indium oxide, iron (II) oxide, iron (III) oxide, magnesium oxide, manganese (II) oxide, mercury (II) oxide, nickel (II) oxide, thallium (III) oxide, tin (II) oxide, and zinc oxide. Improved yields and rates of reaction can be observed with the process of this invention.

Abstract: A method is provided for hydrolyzing organochlorosilanes using concentrated or saturated aqueous hydrogen chloride solution as the source of water. There is employed a ratio of about 10 to about 30 moles of water per mole of organochlorosilane. In addition to recovering gaseous hydrogen chloride without distillation of aqueous hydrogen chloride solution, the organopolysiloxane hydrolyzate in the form of linear and cyclic siloxanes has reduced total chloride content in the form of dissolved hydrogen chloride and chlorine-terminated linear siloxanes.

Abstract: The invention provides a novel continuous process for concurrently producing methyl chloride and organosiloxanes by the reaction of an organochlorosilane and methyl alcohol in an aqueous reaction medium at 70.degree. to 150.degree. C. Different from conventional processes, the aqueous reaction medium contains no catalyst so that the problems inherent to the use of a large amount of a catalyst can be avoided. In the inventive process, the feed rates of the reactants are controlled so as to keep the concentration of hydrogen chloride in the aqueous reaction medium not to exceed the azeotropic concentration thereof at the temperature and under the pressure of operation. These conditions are critical to reduce the loss of hydrogen chloride by dissipation into the gaseous phase resulting in a remarkably high yield of methyl chloride from the standpoint of both the conversion of chlorine content and the space-time yield of the reaction vessel.

Abstract: A method for preparing cyclotetrasiloxane, aliphatic chlorides and/or acyl chlorides from a chlorosilane and an acyloxy compound is disclosed. The chlorosilane and the acyloxy compound may be present as substantially equimolar amounts of separate compounds or they may be present in the same molecule in equimolar amounts. The reactants are merely heated sufficiently, with or without a soluble halide salt catalyst, to form the products. Advantageously this method can provide cyclotetrasiloxanes having water-sensitive radicals such as silicon-bonded chlorine atoms and/or silicon-bonded acyl chloride radicals.

Abstract: A method for preparing cyclotetrasiloxane, aliphatic chlorides and/or acyl chlorides from a cyclotrisiloxane, a chlorosilane and an acyloxy compound is disclosed. The chlorosilane and the acyloxy compound may be present as substantially equimolar amounts of separate compounds or they may be present in the same molecule in equimolar amounts. The reactants are merely heated sufficiently, with or without a soluble halide salt catalyst, to form the products. Advantageously this method can provide cyclotetrasiloxanes having water-sensitive radicals such as silicon-bonded chlorine atoms and/or silicon-bonded acyl chloride radicals. This method also provides a method for preparing cyclotetrasiloxanes having either one type of siloxane unit (non-mixed cyclotetrasiloxanes) or more than one type of siloxane unit (mixed cyclotetrasiloxanes).