Composite solid polymer electrolyte membranes

• US 7,052,793 B2
• Filed: 12/28/2000
• Issued: 05/30/2006
• Est. Priority Date: 08/29/1997
• Status: Expired due to Fees

• Current Assignee: Foster-Miller Incorporated (Thermo Fisher Scientific Incorporated)
• Original Assignee: Foster-Miller Incorporated (Thermo Fisher Scientific Incorporated)
• Inventors: Formato, Richard M., Landrau, Nelson, Kovar, Robert F., Rubin, Leslie S., Osenar, Paul
• Primary Examiner(s): Alejandro, Raymond
• Application Number:
  US09/750,402
• Publication Number:
  US 20020045085A1
• Time in Patent Office: 1,979 Days
• Field of Search: 429/33, 429/41, 429/46, 429/30, 429/309, 429/314, 429/317, 204/518, 204/520, 204/296, 521/27, 521/28, 521/30, 521/33
• US Class Current: 429/535
• CPC Class Codes: B01D 2323/30 Cross-linking
• CPC Class Codes: B01D 61/44 Ion-selective electrodialysis
• CPC Class Codes: B01D 67/0088 Physical treatment with compounds, e.g. swelling, coating or impregnation
• CPC Class Codes: B01D 67/0093 Chemical modification
• CPC Class Codes: B01D 69/141 Heterogeneous membranes, e.g. containing dispersed material; Mixed matrix membranes
• CPC Class Codes: B01D 69/1411 containing dispersed material in a continuous matrix
• CPC Class Codes: B01D 71/32 containing fluorine atoms
• CPC Class Codes: B01D 71/52 Polyethers
• CPC Class Codes: B01D 71/5222 Polyetherketone, polyetheretherketone, or polyaryletherketone
• CPC Class Codes: B01D 71/5223 Polyphenylene oxide, phenyl ether polymers or polyphenylethers
• CPC Class Codes: B01D 71/56 Polyamides, e.g. polyester-amides
• CPC Class Codes: B01D 71/62 Polycondensates having nitrogen-containing heterocyclic rings in the main chain
• CPC Class Codes: B01D 71/64 Polyimides; Polyamide-imides; Polyester-imides; Polyamide acids or similar polyimide precursors
• CPC Class Codes: B01D 71/643 Polyether-imides
• CPC Class Codes: B01D 71/66 Polymers having sulfur in the main chain, with or without nitrogen, oxygen or carbon only
• CPC Class Codes: B01D 71/68 Polysulfones; Polyethersulfones
• CPC Class Codes: B01D 71/82 characterised by the presence of specified groups, e.g. introduced by chemical after-treatment
• CPC Class Codes: C08J 2379/06 Polyhydrazides; Polytriazoles; Polyamino-triazoles; Polyoxadiazoles
• CPC Class Codes: C08J 2381/06 Polysulfones; Polyethersulfones
• CPC Class Codes: C08J 5/2275 Heterogeneous membranes
• CPC Class Codes: H01M 50/414 : Synthetic resins, e.g. thermoplastics or thermosetting resins
• CPC Class Codes: H01M 50/491 : Porosity
• CPC Class Codes: H01M 50/497 : Ionic conductivity
• CPC Class Codes: H01M 8/0289 : Means for holding the electrolyte solid polymer electrolytes H01M8/1018
• CPC Class Codes: H01M 8/1007 : with both reactants being gaseous or vaporised H01M8/12 takes precedence
• CPC Class Codes: H01M 8/1009 : with one of the reactants being liquid, solid or liquid-charged H01M8/12 takes precedence
• CPC Class Codes: H01M 8/1023 : having only carbon, e.g. polyarylenes, polystyrenes or polybutadiene-styrenes
• CPC Class Codes: H01M 8/1027 : having carbon, oxygen and other atoms, e.g. sulfonated polyethersulfones [S-PES]
• CPC Class Codes: H01M 8/103 : having nitrogen, e.g. sulfonated polybenzimidazoles [S-PBI], polybenzimidazoles with phosphoric acid, sulfonated polyamides [S-PA] or sulfonated polyphosphazenes [S-PPh]
• CPC Class Codes: H01M 8/1039 : halogenated, e.g. sulfonated polyvinylidene fluorides
• CPC Class Codes: H01M 8/1044 : Mixtures of polymers, of which at least one is ionically conductive
• CPC Class Codes: H01M 8/106 : characterised by the chemical composition of the porous support
• CPC Class Codes: H01M 8/1062 : characterised by the physical properties of the porous support, e.g. its porosity or thickness
• CPC Class Codes: H01M 8/1067 : characterised by their physical properties, e.g. porosity, ionic conductivity or thickness
• CPC Class Codes: H01M 8/1081 : starting from solutions, dispersions or slurries exclusively of polymers
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y02E 60/50 : Fuel cells
• CPC Class Codes: Y02P 70/50 : Manufacturing or production processes characterised by the final manufactured product

Abstract

The present invention relates to composite solid polymer electrolyte membranes (SPEMs) which include a porous polymer substrate interpenetrated with an ion-conducting material. SPEMs of the present invention are useful in electrochemical applications, including fuel cells and electrodialysis.

Claims

1. A method of producing a composite solid polymer electrolyte membrane (SPEM) comprising a porous polymer substrate interpenetrated with an ion-conducting material, said method comprising the steps of preparing a common solution of the substrate polymer and the ion-conducting material and thereafter casting or extruding the composite SPEM from the solution, and wherein

(i) the porous substrate polymer comprises a homopolymer or copolymer of a liquid crystalline polymer;

and

(ii) the ion-conducting material comprises a homopolymer or copolymer of at least one of a sulfonated, phosphonated or carboxylated ion-conducting aromatic polymer or a perfluorinated ionomer.

2. The method of claim 1, wherein the SPEM is substantially thermally stable to temperatures of at least about 100°

C.

3. The method of claim 1, wherein the SPEM is substantially thermally stable from at least about 100°

C. to at least about 175°

C.

4. The method of claim 1, wherein the liquid crystalline substrate polymer comprises a lyotropic liquid crystalline polymer.

5. The method of claim 4, wherein the lyotropic liquid crystalline substrate polymer comprises at least one of a polybenzazole (PBZ) and polyaramid (PAR) polymer.

6. The method of claim 5, wherein the polybenzazole substrate polymer comprises a homopolymer or copolymer of at least one of a polybenzoxazole (PBO), polybenzothiazole (PBT) and polybenzimidazole (PBI) polymer and the polyaramid polymer comprises a homopolymer or copolymer of a polypara-phenylene terephthalamide (PPTA) polymer.

7. The method of claim 1, wherein the ion-conducting aromatic polymer comprises a wholly aromatic ion-conducting polymer.

8. The method of claim 1, wherein the ion-conducting aromatic polymer comprises a sulfonated, phosphonated or carboxylated polyimide polymer.

9. The method of claim 8, wherein the polyimide polymer is fluorinated.

10. The method of claim 7, wherein the wholly-aromatic ion-conducting polymer comprises a sulfonated derivative of at least one of a polysulfone (PSU), polyphenylene oxide (PPO), polyphenylene sulfoxide (PPSO), polyphenylene sulfide (PPS), polyphenylene sulfide sulfone (PPS/SO₂), polyparaphenylene (PPP), polyphenylquinoxaline (PPQ), polyarylketone (PK), polyetherketone (PEK), polybenzazole (PBZ) and polyaramid (PAR) polymer.

11. The method of claim 10, wherein:

(i) the polysulfone polymer comprises at least one of a polyethersulfone (PES), polyetherethersulfone (PEES), polyarylsulfone, polyarylethersulfone (PAS), polyphenylsulfone (PPSU) and polyphenylenesulfone (PPSO₂) polymer,

(ii) the polybenzazole (PBZ) polymer comprises a polybenzoxaxole (PBO) polymer;

(iii) the polyetherketone (PEK) polymer comprises at least one of a polyetherketone (PEK), polyetheretherketone (PEEK), polyetherketone-ketone (PEKK), polyetheretherketone-ketone (PEEKK) and polyetherketoneetherketone-ketone (PEKEKK) polymer; and

(iv) the polyphenylene oxide (PPO) polymer comprises at least one of a 2,6-diphenyl PPO, 2,6-dimethyl PPO and 1,4-poly phenylene oxide polymer.

12. The method of claim 1, wherein the perfluorinated ionomer comprises a homopolymer or copolymer of a perfluorovinyl ether sulfonic acid.

13. The method of claim 12, wherein the perfluorovinyl ether sulfonic acid is carboxylic- (COOH), phosphonic- (PO(OH)₂) or sulfonic- (SO₃H) substituted.

14. The method of claim 1, wherein the ion-conducting material comprises at least one of a polystyrene sulfonic acid (PSSA), poly(trifluorostyrene) sulfonic acid, polyvinyl phosphonic acid (PVPA), polyacrylic acid and polyvinyl sulfonic acid (PVSA) polymer.

15. The method of claim 1, wherein the porous polymer substrate comprises a homopolymer or copolymer of at least one of a substituted or unsubstituted polybenzazole polymer, and wherein the ion-conducting material comprises a sulfonated derivative of a homopolymer or copolymer of at least one of a polysulfone (PSU), polyphenylene sulfoxide (PPSO) and polyphenylene sulfide sulfone (PPS/SO₂) polymer.

16. The method of claim 15, wherein the polysulfone polymer comprises at least one of a polyethersulfone (PBS) and polyphenylsulfone (PPSU) polymer.

17. The method of claim 15, further comprising cross-linking the ion-conducting material to form sulfone crosslinkages.

18. The method of claim 1, further comprising chlorinating or brominating the ion-conducting material.

19. The method of claim 1, further comprising adding antioxidants to the ion-conducting material.

20. The method of claim 1, further comprising purifying the ion-conducting material.

21. The method of claim 20, wherein purifying the ion-conducting material comprises dissolving the ion-conducting material in a suitable solvent and precipitating the ion-conducting material into a suitable non-solvent.

22. The method of claim 20, wherein purifying the ion-conducting material comprises substantially removing overly sulfonated or degraded fractions of the ion-conducting material.

23. The method of claim 1, wherein the common solution of the substrate polymer and ion-conducting material is prepared in a common solvent.

24. The method of claim 23, wherein the common solvent is selected from the group consisting of tetrahydrofuran (THF), dimethylacetamide (DMAc), dimethylformamide (DMF), dimethylsulfoxide (DMSO), N-Methyl-2-pyrrolidinone (NMP), sulfuric acid, phosphoric acid, chlorosulfonic acid, polyphosphoric acid (PPA) and methanesulfonic acid (MSA).

25. A method of producing a composite solid polymer electrolyte membrane (SPEM) comprising a porous polymer substrate interpenetrated with an ion-conducting material, said method comprising the steps of preparing a common solution of the substrate polymer and the ion-conducting material in a common solvent and thereafter casting or extruding the composite SPEM from the common solution, wherein the porous polymer substrate comprises a homopolymer or copolymer of a liquid crystalline polymer and wherein the SPEM is substantially thermally stable to temperatures of at least about 100°

C.

27. A method as in any of claims 25–

26, wherein the SPEM is stable from at least about 100°

C. to about 175°

C.

28. A method as in any of claims 25–

26, wherein the SPEM is stable from at least about 100°

C. to about 150°

C.

26. A method of producing a composite solid polymer electrolyte membrane (SPEM) comprising a porous polymer substrate interpenetrated with an ion-conducting material, said method comprising the steps of preparing a common solution of the substrate polymer and the ion-conducting material and thereafter extruding or casting a composite film directly from the common solution, wherein the porous polymer substrate comprises a homopolymer or copolymer of a liquid crystalline polymer and wherein the SPEM is substantially thermally stable to temperatures of at least about 100°

C.