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US4417969A
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Sulfonic acid electrolytic cell membranes
Assignee: Dow Chemical Co
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Filing: 1982-01-21
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Granted: 1983-11-29
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Expires: 2002-01-21
Abstract
Abstract An improved polymer for use as an ion exchange membrane in an electrolytic cell wherein the polymer has pendant chains containing sulfonic acid ion exchange groups and has an equivalent weight of between about 800 and about 1500. The polymers have a hydration product of less than about 22,000. The electrolytic cell and its method of operation are described when these polymers are used as ion exchange membranes.
Inventors
- 👤 Bobby R. Ezzell
- 👤 William P. Carl
- 👤 William A. Mod
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:57
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/20; C08J5/22; C08J5/2206; C08J5/2218; C08J5/2231; C08J5/2243; C08J5/225; C25; C25B; C25B1/00; C25B1/01; C25B1/34; C25B1/46; C08J2327/00; C08J2327/02; C08J2327/12; C08J2327/18
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
132 words
An electrolytic cell of the type having (a) an anode in an anode chamber; (b) a cathode in a cathode chamber; (c) an ion exchange membrane separating the cathode chamber from the anode chamber; wherein the ion exchange membrane comprises a polymer having a substantially fluorinated backbone which has pendant groups attached directly to the backbone and represented by the formula ##STR6## where a=0-3 b=0-3 a+b=at least 1 R f and R f ' are independently selected from the group consisting of a halogen and a substantially fluorinated alkyl group having one or more carbon atoms Y is hydrogen or alkali metal wherein the polymer has sulfonate ion exchange groups only, and has an equivalent weight of between about 800 and about 1500 and has a hydration product of less than 22,000.
Claim 2
Dependent Claim
132 words
An electrolytic cell of the type having (a) an anode in an anode chamber; (b) a cathode in a cathode chamber; (c) an ion exchange membrane separating the cathode chamber from the anode chamber; wherein the ion exchange membrane comprises a polymer having a substantially fluorinated backbone which has pendant groups attached directly to the backbone and represented by the formula ##STR6## where a=0-3 b=0-3 a+b=at least 1 R f and R f ' are independently selected from the group consisting of a halogen and a substantially fluorinated alkyl group having one or more carbon atoms Y is hydrogen or alkali metal wherein the polymer has sulfonate ion exchange groups only, and has an equivalent weight of between about 800 and about 1500 and has a hydration product of less than 22,000.
Claim 3
Dependent Claim
43 words
The electrolytic cell of claim 1 wherein the polymer also has recurring pendant groups attached directly to the backbone represented by the general formula ##STR7## where R is a straight or branched substantially fluorinated alkyl chain which may be interrupted by oxygen atoms.
Claim 4
Dependent Claim
19 words
The electrolytic cell of claims 1 or 2 wherein the polymer has a hydration product of less than 20,000.
Claim 5
Dependent Claim
19 words
The electrolytic cell of claims 1 or 2 wherein the polymer has a hydration product of less than 18,000.
Claim 6
Dependent Claim
20 words
The electrolytic cell of claim 1 or 2 wherein the polymer has an equivalent weight of between 800 and 1300.
Claim 7
Dependent Claim
18 words
The electrolytic cell of claim 3 wherein the polymer has an equivalent weight of between 800 and 1300.
Claim 8
Dependent Claim
18 words
The electrolytic cell of claim 4 wherein the polymer has an equivalent weight of between 800 and 1300.
References Cited (Backward Citations)
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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) | 1986-11-28 | 1987-05-30 | 1987-11-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-11-28 | 1991-05-30 | 1991-11-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-11-28 | 1995-05-30 | 1995-11-29 | $7700.00 | Window Closed / Lapsed |