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US4855381A
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Method for the preparation of an organopolysiloxane
Assignee: Shin-Etsu Chemical Co Ltd
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Filing: 1988-06-02
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Granted: 1989-08-08
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Expires: 2008-06-02
Abstract
Abstract An organopolysiloxane composed of tetrafuctional siloxane units SiO 2 and monofunctional siloxane units R 3 SiO 0 .5 can be prepared by reacting an alkyl orthosilicate, e.g., ethyl silicate, or a partial hydrolysis product thereof and an oligomeric organopolysiloxane containing the monofunctional siloxane units in the presence of a catalytic compound which is, different from conventional hydrogen chloride, selected from the group consisting of sulfonic acid group-containing compounds, e.g., sulfuric acid and p-toluene sulfonic acid, and phosphonitrile chloride. In particular, cation exchange resins of sulfonic acid type and fluorinated polysulfonic acid resins can be used as the catalyst in a continuous process in which the reaction mixture is passed through a bed of the catalyst continuously. The inventive method is advantageous over conventional methods because of the absence of the problems of heavy corrosion of the apparatuses and waste disposal due to the hydrogen chloride.
Inventors
- 👤 Kiyoyuki Mutoh
- 👤 Kazushi Satoh
- 👤 Kouichirou Kobayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 15:04
CPC Classifications
C; C08; C08G; C08G77/00; C08G77/02; C08G77/04; C08G77/06
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
82 words
A method for the preparation of an organopolysiloxane containing tetrafunctional siloxane units and monofunctional siloxane units which comprises: reacting an alkyl orthosilicate or a partial hydrolysis product thereof with an oligomeric organopolysiloxane having at least one monofunctional siloxane unit represented by the general formula R 3 SiO 0 .5, in which R is a hydrogen atom or a monovalent hydrocarbon group, in the presence of a catalytic compound selected from the group consisting of a sulfonic acid group-containing compounds and phosphonitrile compounds.
Claim 2
Independent Claim
82 words
A method for the preparation of an organopolysiloxane containing tetrafunctional siloxane units and monofunctional siloxane units which comprises: reacting an alkyl orthosilicate or a partial hydrolysis product thereof with an oligomeric organopolysiloxane having at least one monofunctional siloxane unit represented by the general formula R 3 SiO 0 .5, in which R is a hydrogen atom or a monovalent hydrocarbon group, in the presence of a catalytic compound selected from the group consisting of a sulfonic acid group-containing compounds and phosphonitrile compounds.
Claim 3
Dependent Claim
43 words
The method for the preparation of an organopolysiloxane as claimed in claim 1 wherein the catalytic compound is selected from the group consisting of sulfuric acid, sulfurous acid, fuming sulfuric acid, p-toluene sulfonic acid, acid clay, trifluoromethane sulfonic acid and sodium hydrogen sulfate.
Claim 4
Dependent Claim
25 words
The method for the preparation of an organopolysiloxane as claimed in claim 1 wherein the catalytic compound is a sulfonic acid group-containing cation exchange resin.
Claim 5
Dependent Claim
50 words
The method for the preparation of an organopolysiloxane as claimed in claim 2 wherein the reaction is conducted in the presence of water in an amount in the range from 0.6 to 1.5 moles per mole of the alkoxy groups in the alkyl orthosilicate or a partial hydrolysis product thereof.
Claim 6
Dependent Claim
50 words
The method for the preparation of an organopolysiloxane as claimed in claim 3 wherein the reaction is conducted in the presence of water in an amount in the range from 0.6 to 3.0 moles per mole of the alkoxy groups in the alkyl orthosilicate or a partial hydrolysis product thereof.
Claim 7
Dependent Claim
49 words
The method for the preparation of an organopolysiloxane as claimed in claim 2 wherein the amount of the catalytic compound is in the range from 0.001 to 3% by weight based on the overall amount of the alkyl orthosilicate or a partial hydrolysis product thereof and the oligomeric organopolysiloxane.
Claim 8
Dependent Claim
66 words
The method for the preparation of an organopolysiloxane as claimed in claim 3 wherein the reaction mixture composed of the alkyl orthosilicate or a partial hydrolysis product thereof and the oligomeric organopolysiloxane is admixed with the catalytic compound in an amount of at least 5% by weight based on the overall amount of the alkyl orthosilicate of a partial hydrolysis product thereof and the oligomeric organopolysiloxane.
Claim 9
Dependent Claim
41 words
The method for the preparation of an organopolysiloxane as claimed in claim 3 wherein the reaction mixture composed of the alkyl orthosilicate or a partial hydrolysis product thereof and the oligomeric organopolysiloxane is passed through a bed of the catalytic compound.
Claim 10
Dependent Claim
35 words
The method for the preparation of an organopolysiloxane as claimed in claim 1 wherein the reaction is conducted in the presence of water and at a temperature which initially is from 0° to 25° C.
Claim 11
Dependent Claim
53 words
The method for the preparation of an organosiloxane as claimed in claim 1 wherein the starting oligomeric organopolysiloxane is hexamethyl disiloxane, 1,1,3,3-tetramethyl disiloxane, 1,3-divinyl-1,1,3,3-tetramethyl disiloxane, decamethyl tetrasiloxane, octamethyl cyclotetrasiloxane or a mixture thereof and the starting alkyl orthosilicate is methyl silicate, ethyl silicate, a partial hydrolysis product of either or a mixture thereof.
Claim 12
Dependent Claim
71 words
The method for the preparation of an organopolysiloxane as claimed in claim 10 wherein the catalytic compound is a sulfonic acid group-containing compound selected from the group consisting of sulfuric acid, sulfurous acid, fuming sulfuric acid, p-toluene sulfonic acid, acid clay, trifluoromethane sulfonic acid and sodium hydrogen sulfate and wherein the reaction is conducted in the presence of water and at a temperature which initially is from 0° to 25° C.
Claim 13
Dependent Claim
36 words
The method for the preparation of an organopolysiloxane as claimed in claim 10 wherein the catalytic compound is a sulfonic acid group-containing cation exchange resin and wherein the reaction is conducted in the presence of water.
Claim 14
Dependent Claim
59 words
A method for the preparation of an organopolysiloxane as claimed in claim 1 wherein R is a hydrogen atom or an alkyl, alkenyl, cycloalkyl or aryl group and the catalytic compound is selected from the group consisting of sulfuric acid, sulfurous acid, fuming sulfuric acid, p-toluene sulfonic acid, acid clay, trifluoromethane sulfonic acid, sodium hydrogen sulfate and phosphonitrile compounds.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-08-07 | 1993-02-06 | 1993-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-08-07 | 1997-02-06 | 1997-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-08-07 | 2001-02-06 | 2001-08-08 | $7700.00 | Window Closed / Lapsed |