GB654054A - Improved manufacture of new organo-silicon oxide condensation products - Google Patents

Abstract

An organosilicon oxide condensation product is prepared by reacting a mono-organo-dihalo-silane, wherein the organic radical is monovalent and contains at least five carbon atoms, with water at a temperature of 5 DEG C. or below. Mono-organo-dihalosilanes with the following substituents are specified in examples: (1) amyl; (3) benzyl; (4) phenyl; (5) naphthyl; (6) p-methyl phenyl; (7) p-chlorophenyl Mixtures of (2) lauryl dichlorosilane and tetra decyl dichlorosilane, and (8) hexadecyl dichlorosilane and octadecyl dichlorosilane are also employed. In each case the appropriate alkyl, aryl or alkaryl magnesium chloride is reacted in equimolecular amount with trichlorosilane at -70 DEG C. The product is then hydrolysed while cooling with an ice and salt bath. The hydrolysis is preferably carried out in the presence of an inert solvent, e.g. an ether, an aliphatic or aromatic hydrocarbon, or a halohydrocarbon, and also of a weak alkali, e.g. sodium acetate or bicarbonate. On treatment with oxidizing agents the hydrogen atoms of the polymers are removed and cross-linking oxygen bridges are formed. The hydrogen attached directly to the silicon atoms may be estimated by treating the products with sodium hydroxide and pyridine, and measuring the hydrogen evolved. The products may be used as coatings (becoming resinous by air oxidation). lubricants, hydrophobing agents, e.g. for glass, ceramics, felt, or asbestos. When liquid, they may be used as damping or hydraulic fluids. The product of (2) above, applied to a wire coated with organo-siloxane enamel increases the abrasion resistance. The Specification as open to inspection under Sect. 91 comprises also the use as starting material of mono-organo-dihalosilanes in which the organo-radical contains at least two carbon atoms, and no limitation of the hydrolysis temperature is made. Examples describe the hydrolysis of (1), (2), (3) ethyl dichlorosilane; (5) dihalogeno-silanes with one of the following substituents, n-propyl, isopropyl, n-butyl, isobutyl. Other mixtures specified as starting material are of ethyl dibromosilane and diphenyl dichlorosilane, phenyl dichlorosilane and diethyl monochlorosilane, dodecyl dichlorosilane and dodecyl - ethyl - monochlorosilane, methyl dichlorosilane, diphenyl monochlorosilane and silicon tetrachloride. The subject-matter of Specification 654,099 is also included. This subject-matter does not appear in the Specification as accepted.