Multi-component composite membrane and method for preparing the same

• US 20040213985A1
• Filed: 02/05/2002
• Published: 10/28/2004
• Est. Priority Date: 06/23/2000
• Status: Active Grant

• Current Assignee: LG Energy Solution Limited (LG Corporation)
• Original Assignee: LG Chem Limited (LG Corporation)
• Inventors: Park, Soon-Yong, Lee, Sang-Young, Song, Heon-Sik, Kyung, You-Jin, Ahn, Byeong-In
• Granted Patent: US 7,087,269 B2
• Time in Patent Office: Days
• US Class Current: 428/315.7
• CPC Class Codes: B01D 2323/34 Use of radiation
• CPC Class Codes: B01D 2325/02 Details relating to pores or porosity of the membranes
• CPC Class Codes: B01D 2325/0283 Pore size
• CPC Class Codes: B01D 67/0009 by phase separation, sol-gel transition, evaporation or solvent quenching
• CPC Class Codes: B01D 67/0013 Casting processes
• CPC Class Codes: B01D 67/0027 by stretching
• CPC Class Codes: B01D 67/0083 Thermal after-treatment
• CPC Class Codes: B01D 67/009 with wave-energy, particle-radiation or plasma
• CPC Class Codes: B01D 69/10 Supported membranes; Membrane supports
• CPC Class Codes: B01D 69/12 Composite membranes; Ultra-thin membranes
• CPC Class Codes: B01D 69/1216 Three or more layers
• CPC Class Codes: B01D 71/26 Polyalkenes
• CPC Class Codes: B01D 71/261 Polyethylene
• CPC Class Codes: B01D 71/262 Polypropylene
• CPC Class Codes: B01D 71/34 Polyvinylidene fluoride
• CPC Class Codes: B29C 55/026 of preformed plates or sheets coated with a solution, a dispersion or a melt of thermoplastic material
• CPC Class Codes: B29C 55/065 in several stretching steps
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/0565 Polymeric materials, e.g. gel-type or solid-type
• CPC Class Codes: H01M 50/406 Moulding; Embossing; Cutting
• CPC Class Codes: H01M 50/417 : Polyolefins
• CPC Class Codes: H01M 50/42 : Acrylic resins
• CPC Class Codes: H01M 50/423 : Polyamide resins
• CPC Class Codes: H01M 50/426 : Fluorocarbon polymers
• CPC Class Codes: H01M 50/457 : comprising three or more layers
• CPC Class Codes: H01M 50/489 : Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties
• CPC Class Codes: H01M 50/491 : Porosity
• CPC Class Codes: Y02E 50/30 : Fuel from waste, e.g. synthetic alcohol or diesel
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y10T 428/249979 : Specified thickness of void-containing component [absolute or relative] or numerical cell dimension
• CPC Class Codes: Y10T 428/24998 : Composite has more than two layers
• CPC Class Codes: Y10T 428/265 : 1 mil or less
• CPC Class Codes: Y10T 428/266 : of base or substrate

Abstract

The present invention relates to a multi-component composite separate membrane and a method for preparing the same, and to a multi-component composite membrane comprising a support layer and active layers, wherein the support layer is located between the active layers.

Claims

1. A multi-component composite membrane comprising active layers and support layers, wherein a support layer is located between active layers, wherein the active layers have pores having a pore size and a pore distribution, and wherein the support layer has pores having a different pore size and a different pore distribution.

2. The multi-component composite membrane according to claim 1, wherein a component of a support layer is at least one polymer selected from the group consisting of high density polyethylene, low density polyethylene, linear low density polyethylene, polypropylene, crystalline polypropylene, polyethylene-propylene copolymer, polyethylene-butylene copolymer, polyethylene-hexene copolymer, polyethylene-octene copolymer, polystyrene-butylene-styrene copolymer, polystyrene-ethylene-butylene-styrene copolymer, polystyrene, polyphenylene oxide, polysulfone, polycarbonate, polyester, polyamide, polyurethane, polyacrylate, polyvinylidene choloride, polyvinylidene fluoride, polysiloxane, polyolefin, ionomer, polymethylpentene, and hydrogenated oligocyclopentadiene (HOCP), and a derivative thereof.

3. The multi-component composite membrane according to claim 2, wherein the crystalline polypropylene has one or more physical properties selected from the group consisting of a density of 0.905 g/cc or more, a melting point of 164°

C. or higher, a crystallization temperature of 125°

C. or higher, a crystallinity of 50% or greater, an isotacticity of 96% or greater, and an atactic fraction of 5% or less.

4. The multi-component composite membrane according to claim 1, wherein a pore size of a support layer ranges from 0.001 to 10 μ

m.

5. The multi-component composite membrane according to claim 1, wherein a thickness of a support layer ranges from 1 to 50 μ

m.

6. The multi-component composite membrane according to claim 1, wherein a component of the active layers is one or more polymers selected from the group consisting of polyethylene, polypropylene, polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene copolymer, polyethylene oxide, polypropylene oxide, polybutylene oxide, polyurethane, polyacrylonitrile, polyacrylate, polyacrylic acid, polyamide, polyacrylamide, polyvinylacetate, polyvinylpyrrolidone, polytetraethylene glycol diacrylate, polysulfone, polyphenylene oxide, polycarbonate, polyester, polyvinylidene chloride, polysiloxane, and polyolefin ionomer, and a derivative thereof.

7. The multi-component composite membrane according to claim 6, wherein a solvent for the component of the active layers is one or more solvents selected from the group consisting of 1-methyl-2-pyrrolidone (NMP), acetone, ethanol, n-propanol, n-butanol, n-hexane, cyclohexanol, acetic acid, ethyl acetate, diethyl ether, dimethyl formamide (DMF), dimethylacetamide (DMAc), dioxane, tetrahydrofuran (THF), dimethyl sulfoxide (DMSO), cyclohexane, benzene, toluene, xylene, and water, and a mixture thereof.

8. The multi-component composite membrane according to claim 1, wherein a pore size of an active layer is equal to or less than 10 μ

m.

9. The multi-component composite membrane according to claim 1, wherein a thickness of an active layer ranges from 0.01 to 20 μ

m.

10. The multi-component composite membrane according to claim 1, wherein air permeability of the composite membrane is equal to or less than 7,000 sec/100 cc.

11. The multi-component composite membrane according to claim 1, wherein a wet-out rate of the composite membrane is equal to or less than 30 seconds.

12. The multi-component composite membrane according to claim 1, wherein the composite membrane comprises two or more active layers and one or more support layers, and the composite membrane has a structure of triple or multiple layers.

13. The multi-component composite membrane according to claim 2, wherein the support layer is blended or laminated with at least one polymer.

14. The multi-component composite membrane according to claim 1, wherein the composite membrane is used for water treatment, hemodialysis, enzyme purification, patches for drug delivery, gas separation, pervaporation, reverse osmosis, or electrolysis separation.

15. A separator for batteries comprising the multi-component composite membrane of claim 1.

16. A rechargeable lithium ion battery or a rechargeable lithium ion polymer battery comprising the multi-component composite membrane of claim 1 as a separator.

31. The multi-component composite membrane according to claim 1, wherein the pores of the support layer are formed by a stretching process after orienting a polymer crystalline region in a certain direction and the pores of the active layer are formed by a stretching process after forming a polymer film through phase-inversion.

32. The multi-component composite membrane according to claim 1, wherein an active layer has pores having a pore size equal to or less than 10 μ

m.

47. The multi-component composite membrane according to claim 1, wherein the pores of the support layer are formed by a stretching process and the pores of the active layer are formed by a stretching process after being formed by a phase-inversion.

17. A preparation method of a multi-component composite membrane comprising steps of:

a) preparing a precursor film by injection of a polymer, which is used, for a support layer into an extruder;

b) annealing the precursor film at a temperature less than a melting point of the polymer;

c) coating both surfaces of the precursor film with a polymer solution, which is used for an active layer;

d) drying the coated precursor film;

e) low temperature-stretching the dried precursor film at a temperature less than room temperature;

f) high temperature-stretching the low temperature-stretched precursor film at a temperature less than the melting point of the polymer; and

g) heat-setting the high temperature-stretched precursor film under tension at a temperature less than the melting point of the polymer.

18. The preparation method according to claim 17, wherein the polymer solution of step c) is coated on both sides of the precursor film by dip-coating.

19. The preparation method according to claim 17, wherein a concentration of the polymer solution of step c) is equal to or greater than 0.01 wt %.

20. The preparation method according to claim 17, wherein the drying of step d) is performed at a relative humidity ranging from 1 to 100%.

21. The preparation method according to claim 17, wherein the drying of step d) is performed under saturated vapor pressure.

22. The preparation method according to claim 17, wherein the drying of step d) is performed under a gas atmosphere selected from the group consisting of nitrogen, oxygen, carbon dioxide, and air atmosphere.

23. The preparation method according to claim 17, wherein an active layer having a thickness in the range of 0.1 to 20 μ

m is formed through the coating and drying of steps c) and d).

24. The preparation method according to claim 17, which further comprises the step of applying ion beams to either or both surfaces of the annealed precursor film with reactive gas between the steps b) and c).

25. The preparation method according to claim 24, wherein the ion beam irradiation is performed by activation of electrons and a gas selected from the group consisting of hydrogen, helium, oxygen, nitrogen, carbon dioxide, air, fluorine, neon, argon, krypton, N₂O, and a mixture thereof such that the gas has an energy ranging from 0.01 to 10⁶ keV;

and irradiating-the surface of the precursor film with the ion beams.

26. The preparation method according to claim 24, wherein the ion beam irradiation amount ranges from 10⁵ to 10²⁰ ions/cm².

27. The preparation method according to claim 24, wherein the iron beam irradiation is performed under a gas atmosphere selected from the group consisting of helium, hydrogen, nitrogen, ammonia, carbon monoxide, carbon dioxide, chlorofluoro methane, methane, and N₂O atmospheres, and a mixture thereof.

28. The preparation method according to claim 27, wherein the flow rate of the reactive gas ranges from 0.5 to 20 ml/minute.

30. The preparation method according to claim 24, wherein the ion beam irradiation is performed under a vacuum ranging from10⁻

1 to 10<sup>−

6</sup> torr.

37. A multi-component composite membrane made by the preparation method claimed in claim 17.

38. A multi-component composite membrane made by the preparation method claimed in claim 24.

41. The multi-component composite membrane according to claim 37, wherein the multi-component composite membrane comprises active layers and support layers, wherein a support layer is located between active layers, wherein the active layers have pores having a pore size and a pore distribution, and wherein the support layer has pores having a different pore size and a different pore distribution.

42. The multi-component composite membrane according to claim 41, wherein the pores of the support layer are formed by a stretching process after orienting a polymer crystalline region in a certain direction and the pores of the active layer are formed by a stretching process after forming a densely structured polymer film through phase-inversion.

43. The multi-component composite membrane according to claim 41, wherein the active layer has pores having a pore size equal to or less than 10 μ

m.

29. (Canceled).

33. A preparation method of a multi-component composite membrane comprising steps of:

a) annealing a precursor film comprising a polymer at a temperature less than a melting point of the polymer;

b) coating both surfaces of the precursor film with a polymer solution, which is used for an active layer;

c) drying the coated precursor film;

d) low temperature-stretching the dried precursor film at a temperature less than room temperature;

e) high temperature-stretching the low temperature-stretched precursor film at a temperature less than the melting point of the polymer; and

f) heat-setting the high temperature-stretched precursor film under tension at a temperature less than the melting point of the polymer.

34. The preparation method according to claim 33, wherein the polymer solution of step b) is coated on both sides of the precursor film by dip-coating.

35. The preparation method according to claim 33, which further comprises the step of ion beams to either or both surfaces of the annealed precursor film with reactive gas between the steps a) and b).

36. The preparation method according to claim 35, wherein the ion beam irradiation is performed by activation of electrons and a gas selected from the group consisting of hydrogen, helium, oxygen, nitrogen, carbon dioxide, air, fluorine, neon, argon, krypton, N₂O, and a mixture thereof such that the gas has an energy ranging from 0.01 to 10⁶ keV;

and irradiating the surface of the precursor film with the ion beams.

39. A multi-component composite membrane made by the preparation method claimed in claim 33.

40. A multi-component composite membrane made by the preparation method claimed in claim 35.

44. The multi-component composite membrane according to claim 39, wherein the multi-component composite membrane comprises active layers and support layers, wherein a support layer is located between active layers, wherein the active layers have pores having a pore size and a pore distribution, and wherein the support layer has pores having a different pore size and a different pore distribution.

45. The multi-component composite membrane according to claim 44, wherein the pores of the support layer are formed by a stretching process after orienting a polymer crystalline region in a certain direction and the pores of the active layer are formed by a stretching process after forming a polymer film through phase-inversion.

46. The multi-component composite membrane according to claim 44, wherein the active layer has pores having a pore size equal to or less than 10 μ

m.