Patent US4602045A successfully refreshed from Google Patents.
US4602045A
Expired / Lapsed
US
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Cation-exchange resins and use as membranes in electrolytic cells
Assignee: Orica Ltd
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Filing: 1981-11-26
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Granted: 1986-07-22
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Expires: 2001-11-26
Abstract
Abstract Process of radiation graft polymerizing a fluorinated unsaturated carboxylic acid monomer to a fluoropolymeric permselective membrane in order to improve its performance when used in an electrolysis cell.
Inventors
- 👤 Michael V. Markus
- 👤 George H. Barnett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:30
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/20; C08J5/22; C08J5/2287; C08J5/2293; H; H01; H01M; H01M50/00; H01M50/40; H01M50/409; H01M50/411; H01M50/414; H01M50/426; C08J2327/00; C08J2327/02; C08J2327/12; H01M2300/00; H01M2300/0002; H01M2300/0014; Y; Y02; Y02E; Y02E60/00; Y02E60/10; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31928
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
115 words
A process for treating a fluoropolymeric permselective membrane to improve its resistance to back-migration of hydroxyl ions when it is used in a chloralkali electrolysis cell, which process comprises contacting the surface of a preformed fluoropolymeric permselective membrane derived from a copolymer of tetrafluoroethylene and perfluorovinyl sulfonyl fluoride, with a monomer selected from the group consisting of perfluorobutenoic acid, methyl perfluorobut-3-enoate and ethyl perfluorobut-3-enoate, and then irradiating said membrane, while the surface thereof is in contact with said monomer, with high energy radiation so that the monomer is graft copolymerized onto said membrane, the resulting chemical bonding of the monomer to the polymer membrane increasing the resistance of said membrane to back-migration of hydroxy ions.
Claim 2
Dependent Claim
115 words
A process for treating a fluoropolymeric permselective membrane to improve its resistance to back-migration of hydroxyl ions when it is used in a chloralkali electrolysis cell, which process comprises contacting the surface of a preformed fluoropolymeric permselective membrane derived from a copolymer of tetrafluoroethylene and perfluorovinyl sulfonyl fluoride, with a monomer selected from the group consisting of perfluorobutenoic acid, methyl perfluorobut-3-enoate and ethyl perfluorobut-3-enoate, and then irradiating said membrane, while the surface thereof is in contact with said monomer, with high energy radiation so that the monomer is graft copolymerized onto said membrane, the resulting chemical bonding of the monomer to the polymer membrane increasing the resistance of said membrane to back-migration of hydroxy ions.
Claim 3
Dependent Claim
12 words
A process according to claim 1 wherein the monomer comprises perfluorobut-3-enoic acid.
Claim 4
Dependent Claim
12 words
A process according to claim 1 wherein the monomer comprises methyl perfluorobut-3-enoate.
Claim 5
Dependent Claim
12 words
A process according to claim 1 wherein the monomer comprises ethyl perfluorobut-3-enoate.
Claim 6
Dependent Claim
23 words
A process according to claim 1 wherein the high energy radiation is selected from the group consisting of γ-rays, X-rays and electron beams.
Claim 7
Dependent Claim
21 words
A process according to claim 5 wherein the weight increase in the fluoropolymeric membrane after graft copolymerization is less than 12%.
Claim 8
Dependent Claim
19 words
A process according to claim 6 wherein the said weight increase in the range of from 3 to 5%.
Claim 9
Dependent Claim
12 words
A fluoropolymeric permselective membrane prepared by a process according to claim 1.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-07-21 | 1990-01-20 | 1990-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-07-21 | 1994-01-20 | 1994-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-07-21 | 1998-01-20 | 1998-07-22 | $7700.00 | Window Closed / Lapsed |