US4738764A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrodialysis membranes comprising sulfonated constituents
Assignee: Marmon Industrial Water LLC
•
Filing: 1986-06-02
•
Granted: 1988-04-19
•
Expires: 2006-06-02
Abstract
Abstract Permselective membranes are disclosed which comprise a layer comprising polystyrene, at least a portion of which is sulfonated, and between about 10 wt. % and about 35 wt. % monovinyl arene-hydrogentated diene block copolymer, at least a portion of which is sulfonated. The membranes exhibit a resistance of less than about 8 OMEGA -cm2 in 7 wt. % Na2SO4 and an ion exchange capacity of between about 1.0 meq/g and about 1.6 meq/g. Monopolar and bipolar membranes comprising the layer are disclosed. A preferred process for forming the membranes comprises the steps of sulfonating polystryene and monovinyl arene-hydrogenated diene block copolymer, forming a mixture of the materials in a solvent, forming a layer of the mixture and drying the layer to form at least a portion of the membrane.
Inventors
- 👤 Frederick P. Chlanda
- 👤 Robert S. Cooke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:47
CPC Classifications
B; B01; B01D; B01D61/00; B01D61/42; B01D61/44; B01D61/445; C; C08; C08J; C08J5/00; C08J5/20; C08J5/22; C08J5/2206; C08J5/2218; C08J5/2231; C08J2325/00; C08J2325/02; C08J2325/04
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
57 words
A permselective membrane comprising a layer comprising a mixture of polystyrene, at least a portion of which is sulfonated between about 10 weight percent and about 35 weight percent monovinyl arene-hydrogenated diene block copolymer, at least a portion of which is sulfonated, said layer exhibiting ion exchange capacity of between about 1.0 meq/g and about 1.6 meq/g.
Claim 2
Dependent Claim
57 words
A permselective membrane comprising a layer comprising a mixture of polystyrene, at least a portion of which is sulfonated between about 10 weight percent and about 35 weight percent monovinyl arene-hydrogenated diene block copolymer, at least a portion of which is sulfonated, said layer exhibiting ion exchange capacity of between about 1.0 meq/g and about 1.6 meq/g.
Claim 3
Dependent Claim
17 words
The permselective membrane of claim 1 wherein the monovinyl arene-hydrogenated diene block copolymer is styrene-butadiene block copolymer.
Claim 4
Dependent Claim
16 words
The permselective membrane of claim 1 wherein the copolymer is in the form of a salt.
Claim 5
Dependent Claim
14 words
The permselective membrane of claim 3 wherein the salt cation is a protonated amine.
Claim 6
Dependent Claim
15 words
The permselective membrane of claim 4 wherein the salt cation is a quaternary ammonium salt.
Claim 7
Dependent Claim
22 words
The permselective membrane of claim 1 wherein the amount of monovinyl arene-hydrogenated diene block copolymer is at least about 15 weight percent.
Claim 8
Dependent Claim
23 words
The permselective membrane of claim 1 wherein the ion exchange capacity of the layer is between about 3 meq/g and about 1.6 meq/g.
Claim 9
Dependent Claim
20 words
The permselective membrane of claim 1 wherein the resistance of the layer is less than about 8 Ω-cm 2 .
Claim 10
Dependent Claim
20 words
The permselective membrane of claim 1 wherein the resistance of the layer is less than about 4 Ω-cm 2 .
Claim 11
Dependent Claim
20 words
The permselective membrane of claim 2 wherein the amount of styrene-butadiene block copolymer is at least about 20 weight percent.
Claim 12
Dependent Claim
20 words
The permselective membrane of claim 2 wherein the hydrogen ion capacity is between about 1.0 meq/g and about 1.3 meq/g.
Claim 13
Dependent Claim
23 words
The permselective membrane of claim 6 wherein at least about 10% of the styrene portion of the polystyrene and block copolymer is sulfonated.
Claim 14
Dependent Claim
24 words
The permselective membrane of claim 7 wherein the resistance of the layer is between about 2.5 Ω-cm 2 and about 3.5 Ω-cm 2 .
Claim 15
Dependent Claim
60 words
A cation permselective membrane comprising a layer containing a mixture of polystyrene, at least a portion of which is sulfonated, and between about 10 weight percent and about 35 weight percent monovinyl arene-hydrogenated diene block copolymer, at least a portion of which is sulfonated, said layer exhibiting an ion exchange capacity of between about 1.0 meq/g and about 1.6 meq/g.
Claim 16
Dependent Claim
60 words
A cation permselective membrane comprising a layer containing a mixture of polystyrene, at least a portion of which is sulfonated, and between about 10 weight percent and about 35 weight percent monovinyl arene-hydrogenated diene block copolymer, at least a portion of which is sulfonated, said layer exhibiting an ion exchange capacity of between about 1.0 meq/g and about 1.6 meq/g.
Claim 17
Dependent Claim
19 words
The cation permselective membrane of claim 14 wherein the monovinyl arene-hydrogenated diene block copolymer is a styrene-butadiene block copolymer.
Claim 18
Dependent Claim
23 words
The cation permselective membrane of claim 15 wherein the block copolymer is present in an amount of at least about 15 weight percent.
Claim 19
Dependent Claim
23 words
The cation permselective membrane of claim 14 wherein at least about 10% of the styrene in the polystyrene and block copolymer is sulfonated.
Claim 20
Dependent Claim
21 words
The cation permselective membrane of claim 14 wherein the resistance of the layer is less than about 8 Ω-cm 2 .
Claim 21
Dependent Claim
32 words
The cation permselective membrane of claim 17 wherein the resistance is less than about 4 Ω-cm 2 and wherein the current efficiency in 15 wt. % NaOH is at least about 75%.
Claim 22
Dependent Claim
21 words
The cation permselective membrane of claim 14 wherein the hydrogen ion capacity is between about 1.0 meq/g and about 1.3 meq/g.
Claim 23
Dependent Claim
43 words
A bipolar membrane comprising an anion exchange layer and a cation exchange layer comprising a mixture of sulfonated polystyrene and sulfonated monovinyl arene-hydrogenated diene copolymer, the cation exchange layer having an ion exchange capacity of between about 1.0 meq/g and about 1.6 meq/g.
Claim 24
Dependent Claim
43 words
A bipolar membrane comprising an anion exchange layer and a cation exchange layer comprising a mixture of sulfonated polystyrene and sulfonated monovinyl arene-hydrogenated diene copolymer, the cation exchange layer having an ion exchange capacity of between about 1.0 meq/g and about 1.6 meq/g.
Claim 25
Dependent Claim
14 words
The permselective membrane of claim 1 wherein the permselective membrane is a bipolar membrane.
Claim 26
Dependent Claim
14 words
The permselective membrane of claim 13 wherein the permselective membrane is a bipolar membrane.
Claim 27
Dependent Claim
25 words
The permselective membrane of claim 1 wherein between about 12% and about 20% of the styrene in the polystyrene and the block copolymer is sulfonated.
Claim 28
Independent Claim
40 words
A method of making ion exchange membranes comprising the steps of: (a) forming a mixture comprising sulfonated polystyrene and sulfonated monovinyl arene-hydrogenated (b) forming the mixture into a layer of a prescribed thickness; and, (c) evaporating solvent from the mixture.
Claim 29
Independent Claim
40 words
A method of making ion exchange membranes comprising the steps of: (a) forming a mixture comprising sulfonated polystyrene and sulfonated monovinyl arene-hydrogenated (b) forming the mixture into a layer of a prescribed thickness; and, (c) evaporating solvent from the mixture.
Claim 30
Independent Claim
80 words
The method of making stable permselective membranes comprising the steps of: (a) forming an ion exchange membrane comprising a layer comprising a mixture of sulfonated polystyrene and sulfonated monovinyl arene-hydrogenated diene block copolymer, wherein the layer has an ion exchange capacity of between about 1.0 meq/g and about 1.6 meq/g; and, (b) heating the ion exchange membrane at a temperature of between about 40° C. and about 70° C. in an aqueous salt solution for at least about 2 hours.
Claim 31
Independent Claim
80 words
The method of making stable permselective membranes comprising the steps of: (a) forming an ion exchange membrane comprising a layer comprising a mixture of sulfonated polystyrene and sulfonated monovinyl arene-hydrogenated diene block copolymer, wherein the layer has an ion exchange capacity of between about 1.0 meq/g and about 1.6 meq/g; and, (b) heating the ion exchange membrane at a temperature of between about 40° C. and about 70° C. in an aqueous salt solution for at least about 2 hours.
Claim 32
Dependent Claim
62 words
A permselective membrane comprising a layer comprising a mixture of polystyrene, at least a portion of which is sulfonated, and between about 10 wt % and 35 wt % monovinyl arene-hydrogenated diene block copolymer, at least a portion of which is sulfonated. diene block copolymer having an ion exchange capacity of between about 1.0 meq/g and about 1.6 meq/g in a solvent;
Claim 33
Dependent Claim
62 words
A permselective membrane comprising a layer comprising a mixture of polystyrene, at least a portion of which is sulfonated, and between about 10 wt % and 35 wt % monovinyl arene-hydrogenated diene block copolymer, at least a portion of which is sulfonated. diene block copolymer having an ion exchange capacity of between about 1.0 meq/g and about 1.6 meq/g in a solvent;
References Cited (Backward Citations)
US4166014A
Cited
US4169023A
Cited
US4287042A
Cited
US4326914A
Cited
US4537668A
Cited
US4645579A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-04-19 | 1991-10-19 | 1992-04-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-04-19 | 1995-10-19 | 1996-04-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-04-19 | 1999-10-19 | 2000-04-19 | $7700.00 | Window Closed / Lapsed |