Abstract: A process is disclosed for the continuous transesterification of alkoxysilanes wherein an alkoxysilane is transformed to a different alkoxysilane in the presence of a catalyst and at least one alcohol that provides the different alkoxy group.

Abstract: A process is disclosed for the continuous transesterification of alkoxysilanes wherein an alkoxysilane is transformed to a different alkoxysilane in the presence of a catalyst and at least one alcohol that provides the different alkoxy group.

Abstract: Disclosed is a process in which surface-active additives are used in the slurry phase Direct Synthesis of trialkoxysilanes to shorten the period between the start of the reaction and the attainment of steady-state rates and selectivities, to improve product yields and to control or prevent foam formation. Compositions comprising silicone antifoam compounds and fluorosilicone polymers are the preferred surface-active additives of the instant process.

Abstract: Sulfur-containing organosilicon compounds useful as coupling agents in vulcanizable rubbers to enhance various properties, including low rolling resistance for automobile tires, are prepared. Preferred compounds include .OMEGA., .OMEGA.'-bis (trialkoxysilylalkyl) polysulfides. In one embodiment, the reaction product of ethanolic sodium ethoxide and elemental sulfur is reacted with chloropropyltriethoxysilane. Alternatively, sodium metal is reacted with a mixture of ethanol and elemental sulfur, and then chloropropyltriethoxysilane. The use of sodium metal alcoholates provides an efficient and economical process.

Abstract: Sulfur-containing organosilicon compounds useful as coupling agents in vulcanizable rubbers to enhance various properties, including low rolling resistance for automobile tires, are prepared. Preferred compounds include .OMEGA.,.OMEGA.'-bis (trialkoxysilylalkyl) polysulfides. The compounds are prepared by reacting sodium ethoxylate with hydrogen sulfide gas to yield a sodium sulfide solution, and then reacting this product with a slurried mixture of elemental sulfur and chloropropyltriethoxysilane to form the compound 3,3'-bis (triethoxysilylpropyl) tetrasulfide. The use of hydrogen sulfide gas and sodium metal alcoholates provides an efficient and economical process.

Abstract: Sulfur-containing organosilicon compounds useful as coupling agents in vulcanizable rubbers to enhance various properties, including low rolling resistance for automobile tires, are prepared. Preferred compounds include .OMEGA., 106 '-bis (trialkoxysilylalkyl) polysulfides. In the preferred process scheme, sodium ethoxylate is reacted with hydrogen sulfide gas to yield sodium sulfide. The sodium sulfide is then reacted with sulfur to form the tetrasulfide. The product of that reaction is then reacted with chloropropyltriethoxysilane to form the compound 3,3'- bis (triethoxysilylpropyl) tetrasulfide. The use of hydrogen sulfide gas and sodium metal alcoholates provides an efficient and economical process.

Abstract: In a trimethoxysilane preparation from silicon metal and methanol which preparation uses a solvent, a method for removing a siloxane dissolved in the solvent, which method comprises contacting the solvent with a boron-oxygen compound, and optionally an alkali metal alkoxide such as sodium methoxide.

Abstract: A continuous process for producing trimethoxysilane by reacting methanol and silicon metal in the presence of a copper catalyst, and optionally in an inert solvent, in a multiple reactor system containing at least three reactors by having methanol in substantially vapor form flow countercurrently to a stream containing the silicon metal.

Abstract: A process for producing trimethoxysilane by reacting methanol and silicon metal in the presence of a copper catalyst, and optionally an inert solvent, in which the trimethoxysilane-methanol azeotrope is recycled, characterized by maintaining a 60% methanol conversion.

Abstract: An improved Direct Reaction process which comprises reacting an organohalide with an activated silicon composition, the improvement comprising maintaining the composition of the activated silicon so that it comprises, based on the amount of silicon, 0.05-10 wt. % catalyst; an effective amount of promoter, and 0.001-0.1 wt. % tin, wherein the promoter to tin ratio is 10-250. Activated silicon compositions and methods for selecting a catalyst composition also are provided.

Abstract: An extractive distillation process for recovering trimethoxysilane from a trimethoxysilane-methanol mixture is provided using as the extractive solvent tetramethoxysilane.

Abstract: Disclosed is a process in which surface-active additives are used in the slurry phase Direct Synthesis of trialkoxysilanes to shorten the period between the start of the reaction and the attainment of steady-state rates and selectivities, to improve product yields and to control or prevent foam formation. Compositions comprising silicone antifoam compounds and fluorosilicone polymers are the preferred surface-active additives of the instant process.