Ultra-thin polymer film and porous ultra-thin polymer film

• US 10,858,490 B2
• Filed: 02/22/2018
• Issued: 12/08/2020
• Est. Priority Date: 03/12/2012
• Status: Active Grant

• Current Assignee: Nanotheta Co Ltd., Shinji Takeoka, Toray Industries Incorporated
• Original Assignee: Nanotheta Co Ltd.
• Inventors: Takeoka, Shinji, Saito, Akihiro, Zhang, Hong, Takamizawa, Natsuki
• Primary Examiner(s): Higgins, Gerard
• Application Number:
  US15/902,501
• Publication Number:
  US 20180179352A1
• Time in Patent Office: 1,020 Days
• CPC Class Codes: B01D 2323/18 Pore-control agents or pore formers
• 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 2325/04 Characteristic thickness
• CPC Class Codes: B01D 2325/06 Surface irregularities
• CPC Class Codes: B01D 67/003 by selective elimination of components, e.g. by leaching
• CPC Class Codes: B01D 67/009 with wave-energy, particle-radiation or plasma
• CPC Class Codes: B01D 69/02 characterised by their properties
• CPC Class Codes: B01D 69/122 Separate manufacturing of ultra-thin membranes
• 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 71/48 Polyesters
• CPC Class Codes: B29C 41/12 Spreading-out the material on a substrate , e.g. on the surface of a liquid
• CPC Class Codes: B29C 67/202 comprising elimination of a solid or a liquid ingredient
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: C08J 2333/12 Homopolymers or copolymers of methyl methacrylate
• CPC Class Codes: C08J 2367/04 Polyesters derived from hydroxy carboxylic acids, e.g. lactones C08J2367/06 takes precedence
• CPC Class Codes: C08J 2425/06 Polystyrene
• CPC Class Codes: C08J 5/18 Manufacture of films or sheets
• 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: Y10T 428/21 : Circular sheet or circular blank
• CPC Class Codes: Y10T 428/249979 : Specified thickness of void-containing component [absolute or relative] or numerical cell dimension
• CPC Class Codes: Y10T 442/10 : Scrim [e.g., open net or mesh, gauze, loose or open weave or knit, etc.]

Abstract

A porous ultra-thin polymer film has a film thickness of 10 nm-1000 nm. A method of producing the porous ultra-thin polymer film includes dissolving two types of mutually-immiscible polymers in a first solvent in an arbitrary proportion to obtain a solution; applying the solution onto a substrate and then removing the first solvent from the solution applied onto the substrate to obtain a phase-separated ultra-thin polymer film that has been phase-separated into a sea-island structure; and immersing the ultra-thin polymer film in a second solvent which is a good solvent for the polymer of the island parts but a poor solvent for a polymer other than the island parts to remove the island parts, thereby obtaining a porous ultra-thin polymer film.

Claims

1. A complex of a substrate, a water-soluble sacrificial film and a porous ultra-thin polymer film, comprising the water-soluble sacrificial film on the substrate, and the porous ultra-thin polymer film having a film thickness of 10 nm-1000 nm thereon, wherein the porous ultra-thin polymer film comprises non-penetrating pores.

2. The complex according to claim 1, wherein the pores with a size of 30 nm-50 μ

m are present on the surface of the porous ultra-thin polymer film at a density of 5×

10<sup>−

3</sup> pores/μ

m²-50 pores/μ

m².

3. The complex according to claim 1, wherein the pore diameter distribution in the porous ultra-thin polymer film is at least ±

20%.

4. The complex according to claim 1, wherein the ratio of the pore diameter in microns to the film thickness in microns of the porous ultra-thin polymer film is 0.1-50.

5. The complex according to claim 1, wherein the polymer is at least one selected from the group consisting of polyhydroxyalkanoic acid, a copolymer of polyhydroxyalkanoic acid, poly(ester-ether), a polyester of aliphatic dicarboxylic acid and aliphatic diol, polyamide, polyurethane, polysaccharide ester, poly(acrylate), poly(methacrylate), polystyrene, polyvinyl acetate and polysiloxane.

19. A method of producing a free-standing porous ultra-thin polymer film comprising removing the water-soluble sacrificial film of the complex according to claim 1 with water to obtain a porous ultra-thin polymer film in water.

20. The method according to claim 19, further comprising:

picking up and placing the porous ultra-thin polymer film on another substrate; and

removing the water from the picked up porous ultra-thin polymer film to obtain a porous ultra-thin polymer film in a dry state.

21. A method of producing a complex of a mesh and a porous ultra-thin polymer film, comprising picking up a free-standing porous ultra-thin polymer film produced by the method according to claim 19 with the mesh to produce a complex of the porous ultra-thin polymer film and the mesh.

6. A complex of a substrate, a porous ultra-thin polymer film and a water-soluble support membrane, comprising, in order, the porous ultra-thin polymer film having a film thickness of 10 nm-1000 nm on the substrate, and further the water-soluble support membrane on the porous ultra-thin polymer film, the water-soluble support membrane being selected from the group consisting of a polyvinyl alcohol film, a polyacrylate film, a polymethacrylate film, a sodium alginate film, a polyethylene oxide film, a polyacrylic amide film, a polyvinylpyrrolidone film, a starch film, a carboxymethyl cellulose film, a collagen film, a pullulan film, an agar film, and a silicon film.

7. The complex according to claim 6, wherein the pores with a size of 30 nm-50 μ

m are present on the surface of the porous ultra-thin polymer film at a density of 5×

10<sup>−

3</sup> pores/μ

m²-50 pores/μ

m².

8. The complex according to claim 7, wherein the size of the pores in the porous ultra-thin polymer film is greater than 1 μ

m and less than or equal to 25 μ

m.

9. The complex according to claim 8, wherein the size of the pores in the porous ultra-thin polymer film is greater than 1 μ

m and less than or equal to 15 μ

m.

10. The complex according to claim 6, wherein the pore diameter distribution in the porous ultra-thin polymer film is at least ±

20%.

11. The complex according to claim 6, wherein the ratio of the pore diameter in microns to the film thickness in microns of the porous ultra-thin polymer film is 0.1-50.

12. The complex according to claim 6, wherein the polymer is at least one selected from the group consisting of polyhydroxyalkanoic acid, a copolymer of polyhydroxyalkanoic acid, poly(ester-ether), a polyester of aliphatic dicarboxylic acid and aliphatic diol, polyamide, polyurethane, polysaccharide ester, poly(acrylate), poly(methacrylate), polystyrene, polyvinyl acetate and polysiloxane.

13. The complex according to claim 6, wherein the water-soluble support membrane is a polyvinyl alcohol film.

14. A complex of a porous ultra-thin polymer film and a water-soluble support membrane, comprising the water-soluble support membrane on the porous ultra-thin polymer film having a film thickness of 10 nm-1000 nm, wherein the porous ultra-thin polymer film comprises non-penetrating pores.

15. The complex according to claim 14, wherein the pores with a size of 30 nm-50 μ

m are present on the surface of the porous ultra-thin polymer film at a density of 5×

10<sup>−

3</sup> pores/μ

m²-50 pores/μ

m².

16. The complex according to claim 14, wherein the pore diameter distribution in the porous ultra-thin polymer film is at least ±

20%.

17. The complex according to claim 14, wherein the ratio of the pore diameter in microns to the film thickness in microns of the porous ultra-thin polymer film is 0.1-50.

18. The complex according to claim 14, wherein the polymer is at least one selected from the group consisting of polyhydroxyalkanoic acid, a copolymer of polyhydroxyalkanoic acid, poly(ester-ether), a polyester of aliphatic dicarboxylic acid and aliphatic diol, polyamide, polyurethane, polysaccharide ester, poly(acrylate), poly(methacrylate), polystyrene, polyvinyl acetate and polysiloxane.