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Patent US4102941A successfully refreshed from Google Patents.
US4102941A
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Method for making silarylenesiloxane-polydiorganosiloxane block polymers
Assignee: General Electric Co
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Filing: 1976-11-11
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Granted: 1978-07-25
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Expires: 1996-11-11
Abstract
Abstract A method is provided for making silarylenesiloxane-polydiorganosiloxane block polymers, based on the reaction between a silarylenesilanediol and a silanol terminated polydiorganosiloxane in the presence of a condensation catalyst in the form of an amine salt of certain carboxylic acids. A carbonyl containing organic compound, such as phthalic anhydride, is employed prior to a subsequent devolatilization step to facilitate the removal of amine-carboxylic acid catalyst residues.
Inventors
- 👤 Ronald W. LaRochelle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 09:34
CPC Classifications
C; C08; C08G; C08G77/00; C08G77/42; C08G77/44
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
122 words
A method for making silarylenesiloxane-polydiorsanosiloxane block polymer which comprises (1) refluxing a mixture comprising a silarylene-silanediol, a silanol terminated polydiorganosiloxane, and an inert organic solvent and an effective amount of an amine-carboxylic acid catalyst, (2) adding from 0.01% to 100% by weight of water, based on the weight of the mixture, (3) heating the resulting mixture of (2) to effect the separation of an azeotrope of water and the substantially inert organic solvent until the mixture is substantilaly free of water, (4) adding an amount of an organic carbonyl compound to the mixture of (3), which is effective to facilitate the removal of amine-carboxylic acid catalyst residues, and (5) devolatilizing the mixture of (4) at a temperature of up to 175° C.
Claim 2
Independent Claim
122 words
A method for making silarylenesiloxane-polydiorsanosiloxane block polymer which comprises (1) refluxing a mixture comprising a silarylene-silanediol, a silanol terminated polydiorganosiloxane, and an inert organic solvent and an effective amount of an amine-carboxylic acid catalyst, (2) adding from 0.01% to 100% by weight of water, based on the weight of the mixture, (3) heating the resulting mixture of (2) to effect the separation of an azeotrope of water and the substantially inert organic solvent until the mixture is substantilaly free of water, (4) adding an amount of an organic carbonyl compound to the mixture of (3), which is effective to facilitate the removal of amine-carboxylic acid catalyst residues, and (5) devolatilizing the mixture of (4) at a temperature of up to 175° C.
Claim 3
Dependent Claim
17 words
A method in accordance with claim 1, where the silanol terminated polydiorganosiloxane is a silanol terminated polydimethylsiloxane.
Claim 4
Dependent Claim
13 words
A method in accordance with claim 1, where the silarylenesilanediol is a silphenylenesilanediol.
Claim 5
Dependent Claim
15 words
A method in accordance with claim 1, where the amine-carboxylic acid catalyst is t-butylamine formate.
Claim 6
Dependent Claim
15 words
A method in accordance with claim 1, where the organic carbonyl compound is phthalic anhydride.
Claim 7
Dependent Claim
14 words
A method in accordance with claim 1, where the inert organic solvent is toluene.
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) | 1981-07-24 | 1982-01-23 | 1982-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-24 | 1986-01-23 | 1986-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-24 | 1990-01-23 | 1990-07-25 | $7700.00 | Window Closed / Lapsed |