Ion exchange membrane

Patent metadata

Field	Value
Publication number	US-10413896-B2
Application number	US-201615574301-A
Country	US
Kind code	B2
Filing date	May 16, 2016
Priority date	May 18, 2015
Publication date	Sep 17, 2019
Grant date	Sep 17, 2019

Abstract

The ion exchange membrane according to the present invention comprises a layer A comprising a fluorine-containing polymer having a sulfonic acid group and a layer B comprising a fluorine-containing polymer having a carboxylic acid group, wherein an ion exchange capacity of the layer B is 0.81 mEq/g or more, and a value of (an ion cluster diameter of the layer B)/(an ion cluster diameter of the layer A) is 0.67 to 0.89.

First claim

The invention claimed is:

1. An ion exchange membrane comprising:
a layer A comprising a fluorine-containing polymer having a sulfonic acid group; and
a layer B comprising a fluorine-containing polymer having a carboxylic acid group, wherein
an ion exchange capacity of the layer B is 0.81 mEq/g or more; and
a value of (an ion cluster diameter of the layer B)/(an ion cluster diameter of the layer A) is from 0.67 to 0.89.

2. The ion exchange membrane according to claim 1 , wherein
the ion cluster diameter of the layer A is from 3.0 to 4.5 nm; and
the ion cluster diameter of the layer B is from 1.8 to 4.0 nm.

3. The ion exchange membrane according to claim 1 , wherein a sum of a thickness of the layer A and a thickness of the layer B is 55 μm or more.

4. The ion exchange membrane according to claim 1 , wherein a thickness of the layer A is from 50 to 180 μm.

5. The ion exchange membrane according to claim 1 , wherein a thickness of the layer B is from 5 to 50 μm.

6. The ion exchange membrane according to claim 1 , wherein
the layer A comprises a polymer having a sulfonic acid group derived by hydrolysis a compound represented by the following formula (2); and
the layer B comprises a polymer having a carboxylic acid group derived by hydrolysis from a compound represented by the following formula (3):
CF 2 ═CF—(OCF 2 CYF) a —O—(CF 2 ) b —SO 2 F  (2)

 wherein a represents an integer of 0 to 2, b represents an integer of 1 to 4, and Y represents —F or —CF 3 ; and
CF 2 ═CF—(OCF 2 CYF) c —O—(CF 2 ) d —COOR  (3)

wherein c represents an integer of 1 to 2, d represents an integer of 1 to 4, Y represents —F or —CF 3 , and R represents —CH 3 , —C 2 H 5 , or —C 3 H 7 .

7. An electrolytic cell comprising the ion exchange membrane according to claim 1 .

8. The ion exchange membrane according to claim 2 , wherein a sum of a thickness of the layer A and a thickness of the layer B is 55 μm or more.

9. The ion exchange membrane according to claim 2 , wherein a thickness of the layer A is from 50 to 180 μm.

10. The ion exchange membrane according to claim 3 , wherein a thickness of the layer A is from 50 to 180 μm.

11. The ion exchange membrane according to claim 2 , wherein a thickness of the layer B is from 5 to 50 μm.

12. The ion exchange membrane according to claim 3 , wherein a thickness of the layer B is from 5 to 50 μm.

13. The ion exchange membrane according to claim 4 , wherein a thickness of the layer B is from 5 to 50 μm.

14. The ion exchange membrane according to claim 2 , wherein
the layer A comprises a polymer having a sulfonic acid group derived by hydrolysis a compound represented by the following formula (2); and
the layer B comprises a polymer having a carboxylic acid group derived by hydrolysis from a compound represented by the following formula (3):
CF 2 ═CF—(OCF 2 CYF) a —O—(CF 2 ) b —SO 2 F  (2)

 wherein a represents an integer of 0 to 2, b represents an integer of 1 to 4, and Y represents −F or −CF 3 ; and
CF 2 ═CF—(OCF 2 CYF) c —O—(CF 2 ) d —COOR  (3)

 wherein c represents an integer of 1 to 2, d represents an integer of 1 to 4, Y represents —F or —CF 3 , and R represents —CH 3 , —C 2 H 5 , or —C 3 H 7 .

15. The ion exchange membrane according to claim 3 , wherein
the layer A comprises a polymer having a sulfonic acid group derived by hydrolysis a compound represented by the following formula (2); and
the layer B comprises a polymer having a carboxylic acid group derived by hydrolysis from a compound represented by the following formula (3):
CF 2 ═CF—(OCF 2 CYF) a —O—(CF 2 ) b —SO 2 F  (2)

 wherein a represents an integer of 0 to 2, b represents an integer of 1 to 4, and Y represents —F or —CF 3 ; and
CF 2 ═CF—(OCF 2 CYF) c —O—(CF 2 ) d —COOR  (3)

wherein c represents an integer of 1 to 2, d represents an integer of 1 to 4, Y represents —F or —CF 3 , and R represents —CH 3 , —C 2 H 5 , or —C 3 H 7 .

16. The ion exchange membrane according to claim 4 , wherein
the layer A comprises a polymer having a sulfonic acid group derived by hydrolysis a compound represented by the following formula (2); and
the layer B comprises a polymer having a carboxylic acid group derived by hydrolysis from a compound represented by the following formula (3):
CF 2 ═CF—(OCF 2 CYF) a —O—(CF 2 ) b —SO 2 F  (2)

 wherein a represents an integer of 0 to 2, b represents an integer of 1 to 4, and Y represents —F or —CF 3 ; and
CF 2 ═CF—(OCF 2 CYF) c —O—(CF 2 ) d —COOR  (3)

 wherein c represents an integer of 1 to 2, d represents an integer of 1 to 4, Y represents —F or —CF 3 , and R represents —CH 3 , —C 2 H 5 , or —C 3 H 7 .

17. The ion exchange membrane according to claim 5 , wherein
the layer A comprises a polymer having a sulfonic acid group derived by hydrolysis a compound represented by the following formula (2); and
the layer B comprises a polymer having a carboxylic acid group derived by hydrolysis from a compound represented by the following formula (3):
CF 2 ═CF—(OCF 2 CYF) a —O—(CF 2 ) b —SO 2 F  (2)

 wherein a represents an integer of 0 to 2, b represents an integer of 1 to 4, and Y represents —F or —CF 3 ; and
CF 2 ═CF—(OCF 2 CYF) c —O—(CF 2 ) d —COOR  (3)

 wherein c represents an integer of 1 to 2, d represents an integer of 1 to 4, Y represents —F or —CF 3 , and R represents —CH 3 , —C 2 H 5 , or —C 3 H 7 .

18. An electrolytic cell comprising the ion exchange membrane according to claim 2 .

19. An electrolytic cell comprising the ion exchange membrane according to claim 3 .

20. An electrolytic cell comprising the ion exchange membrane according to claim 4 .

Assignees

• Asahi Chemical Ind

Inventors

• Nakajima Atsushi
• Ajisaka Yasuo
• Kado Yoshifumi
• Sakamoto Naoki

Classifications

• C25B13/02

  characterised by shape or form · CPC title

• C25B9/00

  Cells or assemblies of cells; Constructional parts of cells; Assemblies of constructional parts, e.g. electrode-diaphragm assemblies; Process-related cell features · CPC title

• C08J2327/18

  Homopolymers or copolymers of tetrafluoroethylene · CPC title

• C08J2327/12

  containing fluorine atoms · CPC title

• B32B27/30

  comprising vinyl {(co)polymers; comprising acrylic (co)polymers} · CPC title