Method for producing protective-layer-covered gas separation membrane, protective-layer-covered gas separation membrane, gas separation membrane module, and gas separation apparatus

Patent metadata

Field	Value
Publication number	US-10843137-B2
Application number	US-201815996533-A
Country	US
Kind code	B2
Filing date	Jun 4, 2018
Priority date	Dec 10, 2015
Publication date	Nov 24, 2020
Grant date	Nov 24, 2020

Abstract

A method for producing a protective-layer-covered gas separation membrane includes forming a gas separation membrane having a resin layer containing a compound having a siloxane bond and satisfying a particular condition by surface oxidation treatment of a resin layer precursor containing a siloxane bond; and providing a protective layer on the resin layer before winding. A protective-layer-covered gas separation membrane is produced by the method for producing a protective-layer-covered gas separation membrane. A gas separation membrane module and a gas separation apparatus are produced by the method for producing a protective-layer-covered gas separation membrane.

First claim

What is claimed is:

1. A method for producing a protective-layer-covered gas separation membrane, the method comprising:
forming a gas separation membrane having a resin layer containing a compound having a siloxane bond by surface oxidation treatment of a resin layer precursor containing a siloxane bond with an input power of 23 W or more; and
providing a protective layer on the resin layer before winding,
wherein the gas separation membrane satisfies one of conditions 1, 3, and 4:
condition 1: the resin layer satisfies inequalities 1 and 2:
0.9≥ A/B≥ 0.55  inequality 1:

B≥ 1.7  inequality 2:

wherein A represents an O/Si ratio that is a ratio of the number of oxygen atoms to the number of silicon atoms contained in the resin layer at a depth of 10 nm from a surface of the resin layer, and B represents an O/Si ratio that is a ratio of the number of oxygen atoms to the number of silicon atoms in the surface of the resin layer;
condition 3: a minimum percentage Si 0 of Si 2+ and Si 3+ peaks relative to all Si peaks in ESCA depth profiling of the resin layer is 1% to 40%; and
condition 4: a positron lifetime τ3 of a third component formed by implantation of a positron with an energy of 1 keV into the surface of the resin layer is 3.40 to 4.20 ns.

2. The method for producing a protective-layer-covered gas separation membrane according to claim 1 ,
wherein the gas separation membrane has a porous support A and the resin layer disposed on the porous support A and satisfies condition 2:
condition 2: the compound having a siloxane bond has a repeating unit represented by general formula (2) and a repeating unit represented by general formula (3):

wherein R 11 represents a substituent, * represents a site linked to # in general formula (2) or (3), and # represents a site linked to * in general formula (2) or (3),
the gas separation membrane includes a region GLi where the compound having a siloxane bond is present in the porous support A and a region GLe where the resin layer is present on the porous support A,
GLe has a thickness of 50 to 1,000 nm,
GLi has a thickness of 20 nm or more, and the thickness of GLi is 10% to 350% of the thickness of GLe, and
a difference between a content of the repeating unit represented by general formula (3) in a surface layer of GLe extending to a depth of 20 nm and a content of the repeating unit represented by general formula (3) in a surface layer of GLi extending to a depth of 20 nm is 30% to 90%.

3. The method for producing a protective-layer-covered gas separation membrane according to claim 1 , wherein the surface oxidation treatment is atmospheric-pressure plasma treatment, ultraviolet ozone treatment, corona discharge treatment, or low-pressure plasma treatment.

4. The method for producing a protective-layer-covered gas separation membrane according to claim 1 , wherein the protective layer is provided by coating or vapor deposition.

5. The method for producing a protective-layer-covered gas separation membrane according to claim 1 , wherein the protective layer is provided within 12 hours after completion of the surface oxidation treatment.

6. The method for producing a protective-layer-covered gas separation membrane according to claim 1 , wherein the protective layer contains a silicone resin.

7. The method for producing a protective-layer-covered gas separation membrane according to claim 6 , wherein the silicone resin contains a Si 4+ component.

8. The method for producing a protective-layer-covered gas separation membrane according to claim 6 , wherein an O/Si ratio that is a ratio of the number of oxygen atoms to the number of silicon atoms in an inner portion of the protective layer is less than 1.7.

9. The method for producing a protective-layer-covered gas separation membrane according to claim 1 , wherein the protective layer contains a polyimide resin.

10. The method for producing a protective-layer-covered gas separation membrane according to claim 1 , further comprising:
unwinding a composite having the resin layer precursor from a roll; and
winding the protective-layer-covered gas separation membrane obtained by providing the protective layer into a roll.

11. A protective-layer-covered gas separation membrane comprising:
a gas separation membrane having a resin layer containing a compound having a siloxane bond; and
a protective layer on the resin layer,
wherein the gas separation membrane satisfies one of conditions 3and 4:
condition 3: a minimum percentage Si 0 of Si 2+ and Si 3+ peaks relative to all Si peaks in ESCA depth profiling of the resin layer is 1% to 40%; and
condition 4: a positron lifetime τ3 of a third component formed by implantation of a positron with an energy of 1 keV into the surface of the resin layer is 3.40 to 4.20 ns.

12. The protective-layer-covered gas separation membrane according to claim 11 ,
wherein the gas separation membrane comprises a porous support A and the resin layer disposed on the porous support A and satisfies condition 2:
condition 2: the compound having a siloxane bond has a repeating unit represented by general formula (2) and a repeating unit represented by general formula (3):

wherein R 11 represents a substituent, * represents a site linked to # in general formula (2) or (3), and # represents a site linked to * in general formula (2) or (3),
the gas separation membrane includes a region GLi where the compound having a siloxane bond is present in the porous support A and a region GLe where the resin layer is present on the porous support A,
GLe has a thickness of 50 to 1,000 nm,
GLi has a thickness of 20 nm or more, and the thickness of GLi is 10% to 350% of the thickness of GLe, and
a difference between a content of the repeating unit represented by general formula (3) in a surface layer of GLe extending to a depth of 20 nm and a content of the repeating unit represented by general formula (3) in a surface layer of GLi extending to a depth of 20 nm is 30% to 90%.

13. The protective-layer-covered gas separation membrane according to claim 11 , wherein the gas separation membrane is roll-shaped.

14. A gas separation membrane module comprising the protective-layer-covered gas separation membrane according to claim 11 .

15. A gas separation membrane module comprising a protective-layer-covered gas separation membrane cut from the protective-layer-covered gas separation membrane according to claim 13 .

16. A gas separation apparatus comprising the gas separation membrane module according to claim 15 .

Assignees

• Fujifilm Corp

Inventors

• Mochizuki Yusuke
• Yoneyama Satoshi
• Sawada Makoto

Classifications

• B01D69/1216

  Three or more layers · CPC title

• B01D71/701

  Polydimethylsiloxane · CPC title

• B01D71/64

  Polyimides; Polyamide-imides; Polyester-imides; Polyamide acids or similar polyimide precursors · CPC title

• C08J7/046

  Forming abrasion-resistant coatings; Forming surface-hardening coatings · CPC title

• C08J7/043

  Improving the adhesiveness of the coatings per se, e.g. forming primers (adhesives in the form of films or foils characterised by the primer layers between the polymer carriers and the adhesives C09J7/50) · CPC title