Preparation of porous poly(aryl ether) articles and use thereof

• US 20040222148A1
• Filed: 04/30/2004
• Published: 11/11/2004
• Est. Priority Date: 05/05/2003
• Status: Active Grant

• Current Assignee: Massachusetts Development Finance Agency (STATE OF MASSACHUSETTS)
• Original Assignee: PoroGen Corp. (Air Liquide SA)
• Inventors: Yuan, Youxin
• Granted Patent: US 7,229,580 B2
• Time in Patent Office: Days
• US Class Current: 210/500.39
• CPC Class Codes: B01D 2323/20 Plasticizers
• CPC Class Codes: B01D 2323/21 Fillers
• CPC Class Codes: B01D 2325/10 Catalysts being present on the surface of the membrane or in the pores
• CPC Class Codes: B01D 67/0027 by stretching
• CPC Class Codes: B01D 67/003 by selective elimination of components, e.g. by leaching
• CPC Class Codes: B01D 67/0095 Drying
• CPC Class Codes: B01D 69/12 Composite membranes; Ultra-thin membranes
• CPC Class Codes: B01D 69/1212 Coextruded layers
• CPC Class Codes: B01D 69/1216 Three or more layers
• CPC Class Codes: B01D 71/52 Polyethers
• CPC Class Codes: B01D 71/5223 Polyphenylene oxide, phenyl ether polymers or polyphenylethers
• CPC Class Codes: B01D 71/68 Polysulfones; Polyethersulfones
• CPC Class Codes: B01J 20/26 Synthetic macromolecular compounds
• CPC Class Codes: B01J 20/262 obtained otherwise than by reactions only involving carbon to carbon unsaturated bonds, e.g. obtained by polycondensation macromolecular compounds obtained otherwise than by reactions only involving unsaturated carbon-to-carbon bonds per se C08G
• CPC Class Codes: B01J 20/28014 characterised by their form
• CPC Class Codes: B01J 20/28035 with more than one layer, e.g. laminates, separated sheets
• CPC Class Codes: B01J 20/2809 Monomodal or narrow distribution, uniform pores
• CPC Class Codes: B01J 2220/42 Materials comprising a mixture of inorganic materials materials coated or impregnated on a carrier B01J20/32
• CPC Class Codes: C08J 2201/0462 using organic solvents
• CPC Class Codes: C08J 2371/10 from phenols
• CPC Class Codes: C08J 2479/00 : Characterised by the use of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing nitrogen with or without oxygen, or carbon only, not provided for in groups C08J2461/00 - C08J2477/00
• CPC Class Codes: C08J 9/26 : by elimination of a solid phase from a macromolecular composition or article, e.g. leaching out
• CPC Class Codes: H01M 50/414 : Synthetic resins, e.g. thermoplastics or thermosetting resins
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries

Abstract

The preparation and use of novel porous poly(aryl ether) articles is disclosed. The porous articles are prepared from blends of poly(aryl ether) polymers with polyimides by selectively decomposing the polyimide phase. The preferred reagents used to decompose the polyimide phase include monoethanolamine and tetramethylammonium hydroxide. The porous articles can be configured as a single layer or as a multilayer article. The porous articles of the present invention are unique that at least one of the layers exhibits a narrow pore size distribution. The articles of the present invention can be used as a porous media for a broad range of applications, including porous membranes for fluid separations, such as microfiltration, ultrafiltration, and gas separation, as a battery separators, and as a sorption media.

Claims

1. A process for the preparation of a porous poly(aryl ether) article comprising:

a. forming a blend of poly(aryl ether) polymer with a polyimide,

b. forming a shaped configuration from said poly(aryl ether) polyimide blend,

c. decomposing said polyimide in said shaped configuration into low molecular weight fragments by reacting said polyimide with a primary amine, a secondary amine or a tetramethylammonium hydroxide, and

d. removing said low molecular weight fragments from said shaped configuration.

2. The process of claim 1 wherein said step b) is accomplished by extrusion, casting or molding.

3. The process of claim 1 wherein said primary aliphatic amine is monoethanolamine, ethylamine, propylamine, butylamine, or a mixture thereof.

4. The process of claim 1 wherein said primary aliphatic amine, secondary amine or tetramethylammonium hydroxide are in a solution of alcohol, hydrocarbon, ketone, water, or a mixture thereof.

5. The process of claim 4 wherein said alcohol is methanol, ethanol, isopropanol, or butanol.

6. The process of claim 1 wherein said poly(aryl ether) is polyphenylene oxide, or polysulfone.

7. The process of claim 6 wherein said polysulfone is polyether sulfone, bisphenol A based polysulfone, or biphenol based polysulfone.

8. The process of claim 6 wherein said polyimide is poly(ether imide) of the following repeat unit:

9. The process of claim 1 wherein said shaped configuration is drawn prior to step c) after step d) or both.

10. The process of claim 6 wherein said polysulfone is polyether sulfone and wherein said polyimide is phenylindane containing polyimide.

11. The process of claim 1 wherein said porous article is a flat sheet, a tubular or a hollow fiber fluid separation membrane.

12. The process of claim 11 wherein said membrane is microfiltration, ultrafiltration, nanofiltration or gas separation membrane.

13. The process of claim 11 wherein said fluid separation membrane further contains a separation layer formed on top of the flat sheet, tube or hollow fiber surface.

14. The process of claim 1 wherein said steps c) and d) take place concurrently in a common liquid media.

15. The process of claim 1 further comprising drying the porous article under conditions that substantially preserves the porous structure.

16. The process of claim 15 wherein said drying process is carried out by removing a hydrocarbon, or a fluorocarbon solvent from said porous article.

17. The process of claim 1 wherein said blend contains at least one additive.

18. The process of claim 17 wherein said additive is a solvent, a plasticizer, a catalytic particle, or a filler.

19. The process of claim 1 wherein said poly(aryl ether) article is a multilayer article formed from two or more poly(aryl ether)/polyimide blends that differ in blend chemical composition.

20. The process of claim 19 wherein said multilayer article contains two or more layers that differ in the average pore size.

21. The process of claim 20 wherein the layer comprised of the smaller average pore size is supported or sandwiched between layers with the larger average pore size.

22. The process of claim 1 wherein said article is a battery separator.

23. A process for the preparation of a porous poly(aryl ether) article comprising:

a. forming a casting solution containing a poly(aryl ether), a polyimide and at least one solvent,

b. forming a shaped configuration in the form of a flat sheet, a tube, or a hollow fiber from said casting solution,

c. conveying said shaped configuration through an evaporation zone,

d. solidifying said shaped configuration by contacting it with a coagulation fluid or by a thermally induced quenching,

e. decomposing said polyimide in said shaped configuration into low molecular weight fragments by chemical means,

f. removing said low molecular weight fragments from said shaped configuration.

24. The process of claim 23 wherein said poly(aryl ether) is polysulfone or poly(phenylene oxide).

25. The process of claim 23 wherein step c) is omitted.

26. The process of claim 23 wherein step d) is omitted.

27. The process of claim 23 wherein said at least one solvent is partially or completely removed during step c).

28. The process of claim 23 further comprising drying said shaped configuration, to remove residual solvent under conditions that substantially preserve the porous structure.

29. The process of claim 23 wherein said casting solution further contains a non solvent, a poroformer or a filler.

30. The process of claim 23 wherein said step d) and step e) take place concurrently in a common liquid media.

31. The process of claim 23 wherein said step e) and step f) take place concurrently in a common liquid media.

32. The process of claim 23 further comprise a washing step to remove said solvent after step d) and before step e).

33. The process of claim 23 wherein said polyimide is decomposed by contacting the shaped configuration with tetramethylammonium hydroxide, primary aliphatic amine, secondary aliphatic amine, or a mixture thereof.

34. The process of claim 33 wherein and said primary aliphatic amine is monoethanolamine, ethylamine, propylamine, butylamine, or a mixture thereof.

35. The process of claim 23 wherein said porous article is a microfiltration, an ultrafiltration, a nanofiltration, or a gas separation membrane.

36. The process of claim 35 wherein said microfiltration, ultrafiltration, nanofiltration or gas separation membrane further contain a separation layer formed on top of the flat sheet, tube or hollow fiber surface.

37. The process of claim 23 wherein said porous article is a multilayer article formed from two or more casting solutions that differ in solution chemical composition.

38. The process of claim 37 wherein said multilayer article contains two or more layers that differ in the average pore size.

39. The process of claim 38 wherein the layer comprised of the smaller average pore size is supported by or sandwiched between layers with the larger average pore size.

40. The process of claim 24 wherein said polysulfone is polyether sulfone and said polyimide is phenylindane containing polyimide of the following formula:

41. The process of claim 24 wherein said polysulfone is bisphenol A based polysulfone and said polyimide is phenylindane containing polyimide of the following general formula:

42. The process of claim 23 wherein said poly(aryl ether) is poly(phenylene oxide) and said polyimide is phenylindane containing polyimide of the following general formula:

43. The process of claim 24 wherein said polysulfone is biphenol based polysulfone.

44. The process of claim 24 wherein said flat sheet is supported by a screen or a permeable cloth.

45. A process for the preparation of a porous multilayer poly(aryl ether) article comprising:

a. forming a first blend of poly(aryl ether) polymer with a polyimide;

b. forming at least one additional blend of a poly(aryl ether) polymer with a polyimide wherein the blend composition differs from that of said first blend;

c. forming a shaped article of two or more layers from said poly(aryl ether) polyimide blends by extrusion, casting or molding;

d. decomposing said polyimide in said shaped article into low molecular weight fragments by chemical means; and

e. removing said low molecular weight fragments from said article.

46. The process of claim 45 wherein said poly(aryl ether) in said first blend or said at least one additional blend is polyphenylene oxide, or polysulfone.