Method of making a halosiloxane

Patent metadata

Field	Value
Publication number	US-11098068-B2
Application number	US-201816613130-A
Country	US
Kind code	B2
Filing date	May 24, 2018
Priority date	Jun 6, 2017
Publication date	Aug 24, 2021
Grant date	Aug 24, 2021

Abstract

A method of producing a halosiloxane, the method comprising: i) combining water, a halosilane, and a first solvent to form a reaction mixture, ii) partially hydrolyzing and condensing the halosilane to form a reaction product mixture comprising the halosiloxane, the solvent, unreacted halosilane, and hydrogen halide, iii) adding a second solvent, where the second solvent has a boiling point the boiling point of the halosiloxane, to the reaction mixture in i) or to the reaction product mixture in ii), and iv) recovering the halosiloxane from the reaction product mixture.

First claim

That which is claimed is:

1. A method of producing a halosiloxane, the method comprising:
i) combining water, a halosilane, and a first solvent to form a reaction mixture,
ii) partially hydrolyzing and condensing the halosilane to form a reaction product mixture comprising the halosiloxane, the solvent, unreacted halosilane, and hydrogen halide,
iii) adding a second solvent, where the second solvent has a boiling point≥the boiling point of the halosiloxane, to the reaction mixture in i), to the reaction product mixture in ii), or to the reaction mixture in i) and the reaction product mixture in ii), and
iv) recovering the halosiloxane from the reaction product mixture;
wherein the halosiloxane is a halodisiloxane.

2. A method according to claim 1 , wherein the halosilane is dichlormethylvinylsilane, trichlorovinylsilane, trichlorosilane, tetrachlorosilane or a mixture of trichlorosilane and tetrachlorosilane.

3. A method according to claim 1 , wherein the halodisiloxane is 1,3-dichloro-1,3-dimethyl-1,3-divinyldisiloxane, 1,1,3,3-tetrachloro-1,3-divinyldisiloxane, 1,1,3,3-tetrachlorodisiloxane, 1,1,1,3,3-pentachlorodisiloxane, or hexachlorodisiloxane.

4. A method according to claim 1 , wherein the partial hydrolysis and condensation is at a temperature from −30° C. to the reflux temperature of the halosilane.

5. A method according to claim 1 , wherein the reaction mixture is at a pressure from 0.1 kPa up to 150 kPa.

6. A method according to claim 1 , wherein the second solvent is a hydrocarbon solvent comprising an alkanes, alkene or aromatics, an ethereal solvent comprising a dialkyl ether, glycol ether, crown ether or dioxane, or a polar aprotic solvent comprising a ketone, a nitrile, a formamide, an acetamide, a sulfoxide, an acetate, a phosphoramide, a pyrrolidinone, a nitroalkane, or a carbonate.

7. A method according to claim 6 , wherein the second solvent is tetraethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol dibutyl ether or poly(ethylene glycol) dimethyl ether.

8. A method according to claim 1 , wherein the halosiloxane is recovered from the reaction product mixture by distillation, vacuum stripping, evaporation, extraction or chromatography.

9. A method according to claim 1 , wherein the mole ratio of water to halosilane combined to form the reaction mixture is from 4:1 to 1:100.

10. A method according to claim 1 , wherein the amount of first solvent in the reaction mixture is up to 75% (w/w).

11. A method according to claim 1 , wherein the first solvent and the second solvent are the same.

Assignees

• Dow Silicones Corp

Inventors

• Chang Noel Mower
• Ketola Barry
• Millward Andrew
• Zhou Xiaobing

Classifications

• C07F7/125 Primary

  by reactions involving both Si-C and Si-halogen linkages, the Si-C and Si-halogen linkages can be to the same or to different Si atoms, e.g. redistribution reactions · CPC title

• C01B33/107

  Halogenated silanes · CPC title

• C07F7/126 Primary

  by reactions involving the formation of Si-Y linkages, where Y is not a carbon or halogen atom · CPC title

• C01B33/08 Primary

  Compounds containing halogen · CPC title