Method for producing SiOH-functional polysiloxanes

Patent metadata

Field	Value
Publication number	US-10689490-B2
Application number	US-201616074656-A
Country	US
Kind code	B2
Filing date	Nov 2, 2016
Priority date	Nov 2, 2016
Publication date	Jun 23, 2020
Grant date	Jun 23, 2020

Abstract

Organopolysiloxanes having an OH content of 3.0-10.0% by weight are produced in a continuous process in which silanes of the formula I

R 1 m SiR 2 n X o   (I),

in which
R 1 is a C 1 -C 18 -hydrocarbon radical and R 2 is a C 1 -C 6 -alkoxy radical and X is a chlorine or bromine radical m is 1, 2 or 3, n is 0, 1, 2 or 3 and o is 0, 1, 2 or 3,

with the proviso that 4−m=n+o, and that in at least 30 mol % of the silanes of the general formula I, n≠0 und o≠0,
water, and water-insoluble non-polar solvent are metered in continuously into a reactor to form a reaction mixture and the reaction mixture is continuously discharged from the reactor.

First claim

The invention claimed is:

1. A continuous process for producing organopolysiloxanes having an OH content of 3.0-10.0% by weight, comprising:
continuously metering into a reactor, silanes of the formula I
R 1 m SiR 2 n X o   (I),

in which
R 1 each independently is a C 1 -C 18 -hydrocarbon radical,
R 2 each independently is a C 1 -C 6 -alkoxy radical,
X is a chlorine or bromine radical,
m is 1, 2 or 3,
n is 0, 1, 2 or 3, and
o is 0, 1, 2 or 3,
with the proviso that 4−m=n+o, and that in at least 30 mol % of the silanes of the formula I, n and o are simultaneously other than 0,
and continuously metering water, and non-polar solvent soluble to an extent of not more than 1 g in 1 L of water at 20° C. and 1 bar, into the reactor to form a reaction mixture, and continuously discharging the reaction mixture from the reactor.

2. The process of claim 1 , wherein the silanes of the formula I, water and the non-polar solvent are metered in continuously to the reaction mixture in a loop reactor and the reaction mixture is discharged continuously from the loop reactor.

3. The process of claim 2 , wherein the C 1 -C 18 -hydrocarbon radicals R 1 are selected from the group consisting of methyl radicals, ethyl radicals, propyl radicals, phenyl radicals, and mixtures thereof.

4. The process of claim 1 , wherein the C 1 -C 18 -hydrocarbon radicals R 1 are selected from the group consisting of methyl radicals, ethyl radicals, propyl radicals, phenyl radicals, and mixtures thereof.

5. The process of claim 1 , wherein 10 to 90 mol % of the C 1 -C 18 -hydrocarbon radicals R 1 are phenyl radicals.

6. The process of claim 1 , wherein the C 1 -C 6 -alkoxy radicals R 1 are methoxy and/or ethoxy radicals.

7. The process of claim 1 , wherein at least 80 mol % of the silanes of the formula I have the values 1 or 2 for m.

8. The process of claim 1 , wherein water is metered in in amounts such that a HCl concentration in the water phase of 5-35% by weight is established.

9. The process of claim 1 , wherein the non-polar solvent comprises a hydrocarbon solvent.

10. The process of claim 1 , wherein the silanes of the formula I are produced by reacting halosilanes of the formula III
R 1 q SiX 4-q   (III),

and alkoxysilanes of the formula IV
R 1 r SiR 2 4-r   (IV),

with each other, where
R 1 each individually is a C 1 -C 18 -hydrocarbon radicals,
R 2 each individually is a C 1 -C 6 -alkoxy radical,
X is a chlorine or bromine radical and
q, r are 1, 2 or 3.

Assignees

• Wacker Chemie Ag

Inventors

• Loessel Georg
• Betschinger Frank
• Meisenberger Manfred

Classifications

• C08G77/06 Primary

  Preparatory processes · CPC title

• C08G77/16 Primary

  to hydroxy groups · CPC title