Patent US4673454A successfully refreshed from Google Patents.
US4673454A
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Process for preparing bipolar membranes
Assignee: Chinese Petroleum Corp
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Filing: 1985-09-09
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Granted: 1987-06-16
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Expires: 2005-09-09
Abstract
Abstract An improved bipolar membrane, a precursor for said membrane and a process for preparing bipolar membranes and precursors are described. In the process a precursor is formed by laminating at least two polymeric layers at least one of which is non-ionic. After the formation of the precursor, the non-ionic layer or layers are chemically treated to form a stable bipolar membrane having high permselectivity and low potential drop. The novel bipolar membrane contains an interfacial layer having anionic and cationic domains.
Inventors
- 👤 Kang-Jen Liu
- 👤 Ho-Lun Lee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:51
CPC Classifications
B; B01; B01D; B01D61/00; B01D61/42; B01D61/44; B01D61/445; B32; B32B; B32B27/00; B32B27/30; C; C08; C08J; C08J5/00; C08J5/20; C08J5/22; C08J5/2206; C08J5/2275; C08J2327/00; C08J2327/02; C08J2327/04; C08J2327/06; Y; Y02; Y02A; Y02A20/00; Y02A20/124
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
87 words
A process for preparing a bipolar membrane which comprises intimately contacting a laminate composed of: (1) an anionic or cationic ion-exchange layer; (2) a non-ionic layer containing chemically reactive sites; and (3) an intermediate layer interposed between said layers 1 and 2 and having ion-exchange domains of the same charge as layer 1 and chemically reactive sites; with a reagent which converts the reactive sites in both layers 2 and 3 to ionic groups which have a charge opposite to the charge on said ion-exchange layer 1.
Claim 2
Dependent Claim
87 words
A process for preparing a bipolar membrane which comprises intimately contacting a laminate composed of: (1) an anionic or cationic ion-exchange layer; (2) a non-ionic layer containing chemically reactive sites; and (3) an intermediate layer interposed between said layers 1 and 2 and having ion-exchange domains of the same charge as layer 1 and chemically reactive sites; with a reagent which converts the reactive sites in both layers 2 and 3 to ionic groups which have a charge opposite to the charge on said ion-exchange layer 1.
Claim 3
Dependent Claim
18 words
The process of claim 1 wherein the reactive sites on the intermediate layer are on a polymer matrix.
Claim 4
Dependent Claim
22 words
The process of claim 1 wherein the ion-exchange layers of the bipolar membrane consist of an ion-exchange resin in a matrix polymer.
Claim 5
Dependent Claim
30 words
The process of claim 3 wherein the resin is a cationic ion-exchange resin, and the matrix is vinylbenzyl chloride-styrene copolymer aminated and crosslinked by diamines or polyamines, or mixed amines.
Claim 6
Dependent Claim
42 words
The process of claim 1 wherein the anionic ion-exchange layer of the bipolar membrane comprises an aminated divinylbenzene-vinylbenzyl chloride resin in a matrix polymer and the cationic ion-exchange layer of the bipolar membrane comprises a cationic ion-exchange resin in a matrix polymer.
Claim 7
Dependent Claim
40 words
The process of claim 1 wherein the anionic ion-exchange layer of the bipolar membrane comprises a vinylbenzyl chloride-styrene copolymer aminated with diamines and the cationic ion-exchange layer of the bipolar membrane comprises a cationic ion-exchange resin in a matrix polymer.
Claim 8
Dependent Claim
41 words
The process of claim 1 wherein the anionic ion-exchange layer of the bipolar membrane has juxtaposed thereon an additional anionic ion-exchange layer or the cationic ion-exchange layer of the bipolar membrane has juxtaposed thereon an additional cationic ion-exchange layer or both.
Claim 9
Dependent Claim
27 words
The process of claim 1 wherein the chemically reactive sites are aminated with the reagent and layer 1 is a cationic ion-exchange resin in a polymer matrix.
Claim 10
Dependent Claim
12 words
The process of claim 1 wherein the reagent is an organic amine.
Claim 11
Dependent Claim
19 words
The process of claim 9 wherein the organic amine contains at least two primary, secondary or tertiary amine groups.
Claim 12
Dependent Claim
21 words
The process of claim 10 wherein the organic amine is at least one of the compounds selected from N,N-dimethyl-1,3-propanediamine and N,N,N',N'-tetramethyl-1,6-hexanediamine.
Claim 13
Dependent Claim
23 words
The process of claim 1 wherein the chemically reactive sites are sulfonated with the reagent and layer 1 is an anionic ion-exchange resin.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-06-15 | 1990-12-15 | 1991-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-06-15 | 1994-12-15 | 1995-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-06-15 | 1998-12-15 | 1999-06-16 | $7700.00 | Window Closed / Lapsed |