Patent US4337137A successfully refreshed from Google Patents.
US4337137A
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Composite ion exchange membranes
Assignee: Dow Chemical Co
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Filing: 1980-06-11
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Granted: 1982-06-29
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Expires: 2000-06-11
Abstract
Abstract A composite, substantially completely fluorinated film containing ion exchange groups and its use as an ion exchange membrane in an electrolytic cell is described. The membranes are comprised of at least two layers wherein the layers have equivalent weights that differ by less than 150 and contain ion exchange groups. When each layer contains sulfonyl ion exchange groups the equivalent weight of the two layers differ by less than 250. When the equivalent weight difference exceeds 250, at least one layer has an equivalent weight of less than 1000. The higher equivalent weight layer should face the cathode in an electrolytic cell. When the first layer contains carboxylic acid ion exchange groups and the second layer contains sulfonyl ion exchange groups, at least one layer has an equivalent weight of less than 1000. The carboxylic acid containing layer faces the cathode in an electrolytic cell.
Inventors
- 👤 Bobby R. Ezzell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 09:11
CPC Classifications
C; C25; C25B; C25B13/00; C25B13/04; C25B13/08; C08; C08J; C08J5/00; C08J5/20; C08J5/22; C08J5/2206; C08J5/2275; C08J5/2281; C25B1/00; C25B1/01; C25B1/34; C25B1/46; C08J2327/00; C08J2327/02; C08J2327/12; C08J2327/18
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
106 words
In a polymeric composite film of the type having two layers which differ in equivalent weight, each of said layers having a substantially completely fluorinated polymeric backbone with a plurality of pendant groups attached thereto, at least a portion of said pendant groups being a chain of carbon atoms which may be interrupted with one or more oxygen atoms and which terminates with an ion exchange group; wherein the improvement comprises the two layers differing in equivalent weight from each other by less than 150 and the carbon chain which connects the ion exchange group to the polymeric backbone having from 1 to 3 carbon atoms.
Claim 2
Dependent Claim
106 words
In a polymeric composite film of the type having two layers which differ in equivalent weight, each of said layers having a substantially completely fluorinated polymeric backbone with a plurality of pendant groups attached thereto, at least a portion of said pendant groups being a chain of carbon atoms which may be interrupted with one or more oxygen atoms and which terminates with an ion exchange group; wherein the improvement comprises the two layers differing in equivalent weight from each other by less than 150 and the carbon chain which connects the ion exchange group to the polymeric backbone having from 1 to 3 carbon atoms.
Claim 3
Dependent Claim
26 words
The film of claim 1 where each layer contains ion exchange groups of a different type than the ion exchange groups contained in the other layer.
Claim 4
Dependent Claim
16 words
The film of claim 1 where both layers contain the same type of ion exchange groups.
Claim 5
Dependent Claim
26 words
The film of claim 1 wherein the carbon chain which connects the ion exchange group to the polymeric backbone has from 2 to 3 carbon atoms.
Claim 6
Dependent Claim
23 words
The film of claim 1 wherein the carbon chain which connects the ion exchange group to the polymeric backbone has 2 carbon atoms.
Claim 7
Dependent Claim
20 words
The film of claims 1, 4, or 5 wherein an oxygen atom connects the carbon chain to the polymeric backbone.
Claim 8
Dependent Claim
50 words
In an electrolytic cell of the type having an anode in an anode compartment and a cathode in a cathode compartment, said anode and cathode being separated by an ion exchange membrane, wherein the improvement comprises the membrane being the film of claims 1, 2, 3, 4, 5 or 6.
Claim 9
Dependent Claim
61 words
In an electrolytic cell of the type having an anode in an anode compartment and a cathode in a cathode compartment, said anode and cathode being separated by an ion exchange membrane, wherein the improvement comprises the membrane being the film of claims 1, 2, 3, 4, 5 or 6, wherein the layer having the higher equivalent weight faces the cathode.
Claim 10
Dependent Claim
110 words
In a polymeric composite film of the type having at least two layers which differ in equivalent weight, each of said layers having a substantially completely fluorinated polymeric backbone with a plurality of pendant groups attached thereto, at least a portion of said pendant groups being a chain of carbon atoms which may be interrupted with one or more oxygen atoms and which terminates with a sulfonyl ion exchange group; wherein the improvement comprises the two layers differing in equivalent weight from each other by less than 250 and the carbon chain which connects the sulfonyl ion exchange group to the polymeric backbone having from 1 to 3 carbon atoms.
Claim 11
Dependent Claim
110 words
In a polymeric composite film of the type having at least two layers which differ in equivalent weight, each of said layers having a substantially completely fluorinated polymeric backbone with a plurality of pendant groups attached thereto, at least a portion of said pendant groups being a chain of carbon atoms which may be interrupted with one or more oxygen atoms and which terminates with a sulfonyl ion exchange group; wherein the improvement comprises the two layers differing in equivalent weight from each other by less than 250 and the carbon chain which connects the sulfonyl ion exchange group to the polymeric backbone having from 1 to 3 carbon atoms.
Claim 12
Dependent Claim
27 words
The film of claim 9 wherein the carbon chain which connects the sulfonyl ion exchange group to the polymeric backbone has from 2 or 3 carbon atoms.
Claim 13
Dependent Claim
19 words
The film of claims 9 or 10 wherein an oxygen atom connects the carbon chain to the polymeric backbone.
Claim 14
Dependent Claim
46 words
In an electrolytic cell of the type having an anode in an anode compartment and a cathode in a cathode compartment, said anode and cathode being separated by an ion exchange membrane, wherein the improvement comprises the membrane being the film of claim 9 or 10.
Claim 15
Dependent Claim
44 words
In an electrolytic cell of the type having an anode in an anode compartment and a cathode in a cathode compartment, said anode and cathode being separated by an ion exchange membrane. wherein the improvement comprises the membrane being the film of claim 11.
Claim 16
Dependent Claim
59 words
In an electrolytic cell of the type having an anode in an anode compartment and a cathode in a cathode compartment, said anode and cathode being separated by an ion exchange membrane, wherein the improvement comprises the membrane being the film of claim 9 where the layer of the film having the greater equivalent weight faces the cathode compartment.
Claim 17
Dependent Claim
43 words
In a substantially completely fluorinated polymeric composite film having a first layer containing carboxylic acid ion exchange groups and a second layer containing sulfonyl ion exchange groups, wherein the improvement comprises at least one layer having an equivalent weight of less than 1000.
Claim 18
Dependent Claim
43 words
In a substantially completely fluorinated polymeric composite film having a first layer containing carboxylic acid ion exchange groups and a second layer containing sulfonyl ion exchange groups, wherein the improvement comprises at least one layer having an equivalent weight of less than 1000.
Claim 19
Dependent Claim
32 words
The film of claim 15 wherein the sulfonyl ion exchange group is attached to a carbon chain having from 1 to 4 carbon atoms which is, itself, connected to a polymeric backbone.
Claim 20
Dependent Claim
17 words
The film of claim 16 where an oxygen atom connects the carbon chain to the polymeric backbone.
Claim 21
Dependent Claim
15 words
The film of claim 15 wherein both layers have equivalent weights of less than 1000.
Claim 22
Dependent Claim
17 words
The film of claim 15 wherein the first layer has an equivalent weight of less than 1000.
Claim 23
Dependent Claim
64 words
In an electrolytic cell of the type having an anode in an anode compartment and a cathode in a cathode compartment, said anode and cathode being separated by an ion exchange membrane, wherein the improvement comprises the membrane being the film of claims 15, 16, 17, 18 or 19 wherein the film is positioned such that the first layer thereof faces the cathode compartment.
Claim 24
Dependent Claim
104 words
In a polymeric composite film of the type having two layers which differ from each other in equivalent weights by at least 250, each of said layers having a substantially completely fluorinated polymeric backbone with a plurality of pendant groups attached thereto, at least a portion of said pendant groups being a chain of carbon atoms which may be interrupted with one or more oxygen atoms and which terminates with a sulfonyl ion exchange group; wherein the improvement comprises at least one layer having an equivalent weight of less than 1000 and the chain of carbon atoms having from 1 to 3 carbon atoms.
Claim 25
Dependent Claim
104 words
In a polymeric composite film of the type having two layers which differ from each other in equivalent weights by at least 250, each of said layers having a substantially completely fluorinated polymeric backbone with a plurality of pendant groups attached thereto, at least a portion of said pendant groups being a chain of carbon atoms which may be interrupted with one or more oxygen atoms and which terminates with a sulfonyl ion exchange group; wherein the improvement comprises at least one layer having an equivalent weight of less than 1000 and the chain of carbon atoms having from 1 to 3 carbon atoms.
Claim 26
Dependent Claim
18 words
The film of claim 21 wherein an oxygen atom connects the chain of carbon atoms to the backbone.
Claim 27
Dependent Claim
32 words
An electrolytic cell comprising an anode in an anode compartment and a cathode in a cathode compartment separated by an ion exchange membrane comprised of the film of claim 22 or 21.
Claim 28
Dependent Claim
24 words
The cell of claim 23, wherein the first the first layer of the film has the higher equivalent weight and faces the cathode compartment.
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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) | 1985-06-28 | 1985-12-28 | 1986-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-06-28 | 1989-12-28 | 1990-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-06-28 | 1993-12-28 | 1994-06-29 | $7700.00 | Window Closed / Lapsed |