US4340680A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cation exchange membrane of fluorinated polymer for an electrolysis
Assignee: AGC Inc
•
Filing: 1980-07-23
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Granted: 1982-07-20
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Expires: 2000-07-23
Abstract
Abstract A cation exchange membrane of a fluorinated polymer for an electrolysis comprises a structure of a copolymer of a fluorinated olefin and a fluorovinyl compound having the formula CF.sub.2 ═CX--(OCF.sub.2 CFY).sub.l (O).sub.m (CFY').sub.n COOM wherein X represents --F or --CF 3 ; Y and Y' respectively represents --F or a C 1 -C 10 perfluoroalkyl group; l is 0 to 3; m is 0 or 1; n is 0 to 12 and M represents hydrogen atom or an alkali metal atom; and a modified surface layer of said cation exchange membrane in an anode side which has --SO 3 M groups formed by converting --COOM groups.
Inventors
- 👤 Tatsuro Asawa
- 👤 Masaaki Yamabe
- 👤 Haruhisa Miyake
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:25
CPC Classifications
C; C25; C25B; C25B1/00; C25B1/01; C25B1/34; C25B1/46; C08; C08J; C08J5/00; C08J5/20; C08J5/22; C08J5/2206; C08J5/2218; C08J5/2231; C08J5/2243; C08J5/225; C08J2327/00; C08J2327/02; C08J2327/12
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
125 words
A cation exchange membrane of a fluorinated polymer for an electrolysis which comprises a structure of a copolymer of a fluorinated olefin and a fluorovinyl compound having the formula: CF.sub.2 ═CX--(OCF.sub.2 CFY).sub.l (O).sub.m (CFY').sub.n COOM wherein X represents --F or --CF 3 ; Y and Y' respectively represents --F or C 1 -C 10 perfluoroalkyl group; l is 0 to 3; m is 0 or 1; n is 0 to 12 and M represents hydrogen atom or an alkali metal atom; and one modified surface layer of said cation exchange membrane on an anode side which has --SO 3 M groups formed from --COOM groups of said copolymer, wherein said modified surface layer does not extend to more than 1/3 the thickness of said membrane.
Claim 2
Dependent Claim
125 words
A cation exchange membrane of a fluorinated polymer for an electrolysis which comprises a structure of a copolymer of a fluorinated olefin and a fluorovinyl compound having the formula: CF.sub.2 ═CX--(OCF.sub.2 CFY).sub.l (O).sub.m (CFY').sub.n COOM wherein X represents --F or --CF 3 ; Y and Y' respectively represents --F or C 1 -C 10 perfluoroalkyl group; l is 0 to 3; m is 0 or 1; n is 0 to 12 and M represents hydrogen atom or an alkali metal atom; and one modified surface layer of said cation exchange membrane on an anode side which has --SO 3 M groups formed from --COOM groups of said copolymer, wherein said modified surface layer does not extend to more than 1/3 the thickness of said membrane.
Claim 3
Dependent Claim
40 words
The cation exchange membrane according to claim 1 wherein said fluorovinyl compound is a compound having the formula ##STR3## wherein p is 0 or 1; q is 1 to 5 and M represents hydrogen atom or an alkali metal atom.
Claim 4
Dependent Claim
44 words
The cation exchange membrane according to claim 1 or 2 wherein said cation exchange membrane has a modified surface layer having --OCF 2 SO 3 M groups on an anode side and a surface layer having --OCF 2 COOM groups on a cathode side.
Claim 5
Dependent Claim
36 words
The cation exchange membrane according to claim 1, wherein said surface layer of said cation exchange membrane on an anode side has --SO 3 M groups as ion-exchange groups to a depth of at least 1.0μ.
Claim 6
Dependent Claim
34 words
The cation exchange membrane according to claim 1, wherein the ion exchange capacity of --SO 3 M groups in said modified surface layer is in the range of 1.0 to 4.0 meq./g. dry polymer.
Claim 7
Dependent Claim
32 words
The cation exchange membrane according to claim 1, wherein --COOM groups are converted into --SO 3 M groups through intermediate groups of --CF═CF 2 , --CF 2 H or --CF 2 I.
Claim 8
Dependent Claim
31 words
The cation exchange membrane according to claim 1, wherein said electrolysis is an electrolysis of an aqueous solution of an alkali metal chloride to produce an alkali metal hydroxide and chlorine.
References Cited (Backward Citations)
JPS5224177A
Cited
US4151053A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-07-19 | 1986-01-18 | 1986-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-07-19 | 1990-01-18 | 1990-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-07-19 | 1994-01-18 | 1994-07-20 | $7700.00 | Window Closed / Lapsed |