Patent US584148A successfully refreshed from Google Patents.
Patent US4295952A successfully refreshed from Google Patents.
US4295952A
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US
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Novel cationic membranes
Assignee: De Nora SpA
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Filing: 1980-03-24
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Granted: 1981-10-20
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Expires: 2000-03-24
Abstract
Abstract Cationic membranes permeable to ions but fluid impermeable comprising a partly sulfonated terpolymer of styrene, divinylbenzene and at least one member of the group consisting of 2-vinylpyridine, 4-vinylpyridine and acrylic acid, the degree of sulfonation varying through the membrane cross-section from a maximum or the anodic surface to a minimum at the cathodic surface, their preparation, their use in electrolysis cells and electrochemical processes.
Inventors
- 👤 Oronzio De Nora
- 👤 Luigi Giuffre
- 👤 Giovanni Modica
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:05
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/20; C08J5/22; C08J5/2287; C08J2339/00; C08J2339/04; C08J2339/08; C08J2353/00; C08J2353/02
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
49 words
A membrane electrochemical cell comprising a cell housing containing at least one anode in an anode compartment and at least one cathode in a cathode compartment forming an interelectrodic gap with a cation exchange membrane separating the anode and cathode compartments with the sulfonated polymer facing the anodic side.
Claim 2
Dependent Claim
49 words
A membrane electrochemical cell comprising a cell housing containing at least one anode in an anode compartment and at least one cathode in a cathode compartment forming an interelectrodic gap with a cation exchange membrane separating the anode and cathode compartments with the sulfonated polymer facing the anodic side.
Claim 3
Dependent Claim
56 words
The cell of claim 1 wherein the sulfonated terpolymer is a terpolymer of styrene, divinylbenzene and at least one member of the group consisting of 2- and 4-vinylpyridine wherein the molar ratio of styrene to the vinylpyridine is between 1/8 and 1/1 and the molar percentage of divinylbenzene in the copolymer is from 8 to 20%.
Claim 4
Dependent Claim
52 words
The cell of claim 1 wherein the membrane comprises a first layer of a water wettable and water insoluble sulfonated polymer of styrene and divinylbenzene and a second layer of an unsulfonated polymer of divinylbenzen and at least one monomer selected from the group consisting of 2-vinylpyridine and 4-vinylpyridine and acrylic acid.
Claim 5
Dependent Claim
27 words
The cell of claim 1 wherein the first layer polymer also contains at least one member of the group consisting of 2-vinylpyridine and 4-vinylpyridine and acrylic acid.
Claim 6
Dependent Claim
67 words
A fluid impermeable cation exchange membrane comprising a first layer of a water wettable and water insoluble sulfonated polymer of styrene and about 8 to 20 molar percent of divinylbenzene and a second layer of an unsulfonated polymer of divinylbenzene and at least one monomer selected from the group consisting of 2-vinylpyridine and 4-vinylpyridine in a molar ratio of styrene to vinylpyridine of about 1:8 to 1:1.
Claim 7
Dependent Claim
67 words
A fluid impermeable cation exchange membrane comprising a first layer of a water wettable and water insoluble sulfonated polymer of styrene and about 8 to 20 molar percent of divinylbenzene and a second layer of an unsulfonated polymer of divinylbenzene and at least one monomer selected from the group consisting of 2-vinylpyridine and 4-vinylpyridine in a molar ratio of styrene to vinylpyridine of about 1:8 to 1:1.
Claim 8
Dependent Claim
26 words
The membrane of claim 5 wherein the first layer polymer also contains at least one member of the group consisting of 2-vinylpyridine, 4-vinylpyridine and acrylic acid.
Claim 9
Dependent Claim
13 words
The membrane of claim 5 wherein the second layer polymer also contains styrene.
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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) | 1984-10-19 | 1985-04-20 | 1985-10-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-19 | 1989-04-20 | 1989-10-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-19 | 1993-04-20 | 1993-10-20 | $7700.00 | Window Closed / Lapsed |