Process for preparing membranes

Patent metadata

Field	Value
Publication number	US-9586182-B2
Application number	US-201314408808-A
Country	US
Kind code	B2
Filing date	Jun 26, 2013
Priority date	Jun 26, 2012
Publication date	Mar 7, 2017
Grant date	Mar 7, 2017

Abstract

A process for preparing a composite membrane comprising the steps: a) applying a radiation-curable composition to a porous support; b) irradiating the composition and thereby forming a gutter layer of cured polymer; and c) forming a discriminating layer on the gutter layer; wherein the radiation-curable composition comprises a partially crosslinked, radiation-curable polymer comprising epoxy groups and siloxane groups, a photoinitiator and is substantially free from mono-epoxy compounds. Composite membranes and gas separation cartridges are also claimed.

First claim

The invention claimed is:

1. A process for preparing a composite membrane comprising the steps:
a) applying a radiation-curable composition to a porous support;
b) irradiating the composition and thereby forming a gutter layer of cured polymer; and
c) forming a discriminating layer on the gutter layer;
wherein the radiation-curable composition comprises a partially crosslinked, radiation-curable polymer comprising epoxy groups and siloxane groups, a photoinitiator and is substantially free from mono-epoxy compounds.

2. The process according to claim 1 , wherein the radiation-curable composition contains less than 0.1 wt % of mono-epoxy compounds and the discriminating layer is formed from a composition containing less than 0.1 wt % of mono-epoxy compounds.

3. The process according to claim 1 , wherein the radiation-curable composition contains less than 0.01 wt % of mono-epoxy compounds and the discriminating layer is formed from a composition containing less than 0.01 wt % of mono-epoxy compounds.

4. The process according to claim 1 , wherein the radiation-curable composition is free from mono-epoxy compounds and the discriminating layer is formed from a composition which is free from mono-epoxy compounds.

5. The process according to claim 1 , wherein the discriminating layer comprises a polyimide, cellulose acetate, polybenzoxazole, polyethyleneoxide or polyetherimide.

6. The process according to claim 1 , wherein the discriminating layer comprises a polyimide comprising trifluoromethyl groups.

7. The process according to claim 1 , wherein the discriminating layer comprises poly([({2,3,5,6-tetramethyl-1,4-phenylenediamine}-alt-{5,5′-[2,2,2-trifluoro-1-(trifluoromethyl)ethane-1,1-diyl]bis(isobenzofuran-1,3-dione)})-co-[{5-carboxylic-1,3-phenylenediamine}-alt-{5,5′-[2,2,2-trifluoro-1-(trifluoromethyl)ethane-1,1-diyl]bis(isobenzofuran-1,3-dione)}]).

8. The process according to claim 1 , wherein:
the radiation-curable composition is applied continuously to the porous support in step a) by means of a manufacturing unit comprising a radiation-curable composition application station, step b) is performed using an irradiation source located downstream from the radiation-curable composition application station, the discriminating layer is formed on the layer of cured polymer in step c) by a discriminating layer application station, and the resultant composite membrane is collected at a collecting station, wherein the manufacturing unit comprises a means for moving the porous support from the radiation-curable composition application station to the irradiation source and to the discriminating layer application station and to the composite membrane collecting station.

9. The process according to any of the previous claim 1 , wherein step a) and/or step b) is or are performed by curtain coating, meniscus type dip coating, kiss coating, pre-metered slot die coating, reverse or forward kiss gravure coating, multi roll gravure coating, spin coating and/or slide bead coating.

10. A composite membrane prepared by the method according claim 1 .

11. A gas separation cartridge comprising the composite membrane according to claim 1 wherein the cartridge is of plate-and-frame, spiral-wound, hollow-fibre, tubular or envelope type.

12. The process according to claim 1 wherein:
(a) the radiation-curable composition contains less than 0.1 wt % of mono-epoxy compounds;
(b) the discriminating layer is formed from a composition containing less than 0.1 wt % of mono-epoxy compounds; and
(c) the discriminating layer comprises poly([({2,3,5,6-tetramethyl-1,4-phenylenediamine}-alt-{5,5′-[2,2,2-trifluoro-1-(trifluoromethyl)ethane-1,1-diyl]bis(isobenzofuran-1,3-dione)})-co-[{5-carboxylic-1,3-phenylenediamine}-alt-{5,5′-[2,2,2-trifluoro-1-(trifluoromethyl)ethane-1,1-diyl]bis(isobenzofuran-1,3-dione)}]).

13. The process according to claim 12 wherein the radiation-curable composition contains less than 0.01 wt % of mono-epoxy compounds and the discriminating layer is formed from a composition containing less than 0.01 wt % of mono-epoxy compounds.

14. The process according to claim 1 wherein:
the radiation-curable composition is applied continuously to the porous support in step a) by means of a manufacturing unit comprising a radiation-curable composition application station, step b) is performed using an irradiation source located downstream from the radiation-curable composition application station, the discriminating layer is formed on the layer of cured polymer in step c) by a discriminating layer application station, and the resultant composite membrane is collected at a collecting station, wherein the manufacturing unit comprises a means for moving the porous support from the radiation-curable composition application station to the irradiation source and to the discriminating layer application station and to the composite membrane collecting station and wherein the discriminating layer comprises poly([({2,3,5,6-tetramethyl-1,4-phenylenediamine}-alt-{5,5′-[2,2,2-trifluoro-1-(trifluoromethyl)ethane-1,1-diyl]bis(isobenzofuran-1,3-dione)})-co-[{5-carboxylic-1,3-phenylenediamine}-alt-{5,5′-[2,2,2-trifluoro-1-(trifluoromethyl)ethane-1,1-diyl]bis(isobenzofuran-1,3-dione)}]).

15. The process according to claim 14 wherein step a) and/or step b) is or are performed by curtain coating, meniscus type dip coating, kiss coating, pre-metered slot die coating, reverse or forward kiss gravure coating, multi roll gravure coating, spin coating and/or slide bead coating.

16. A composite membrane comprising:
i) a porous support;
ii) a gutter layer obtained from curing a radiation-curable composition comprising a photoinitiator and a partially crosslinked, radiation-curable polymer comprising epoxy groups and siloxane groups, said composition being substantially free from mono-epoxy compounds; and
iii) a discriminating layer on the gutter layer.

17. The composite membrane according to claim 16 wherein the discriminating layer has been obtained from a composition which is substantially free from mono-epoxy compounds.

18. The composite membrane according to claim 16 wherein the discriminating layer comprises poly([({2,3,5,6-tetramethyl-1,4-phenylenediamine}-alt-{5,5′-[2,2,2-trifluoro-1-(trifluoromethyl)ethane-1,1-diyl]bis(isobenzofuran-1,3-dione)})-co-[{5-carboxylic-1,3-phenylenediamine}-alt-{5,5′-[2,2,2-trifluoro-1-(trifluoromethyl)ethane-1,1-diyl]bis(isobenzofuran-1,3-dione)}]).

19. A gas separation cartridge comprising the composite membrane according to claim 16 wherein the cartridge is of plate-and-frame, spiral-wound, hollow-fibre, tubular or envelope type.

20. A gas separation cartridge comprising the composite membrane according to claim 17 wherein the cartridge is of plate-and-frame, spiral-wound, hollow-fibre, tubular or envelope type.

Assignees

• Fujifilm Mfg Europe Bv

Inventors

• Umehara Takeshi
• Van Kessel Petrus
• Itami Yujiro

Classifications

• B01D53/228

  characterised by specific membranes · CPC title

• Y02C10/10

  Cross-Sectional Technologies · mapped topic

• B01D2323/30

  Cross-linking · CPC title

• B01D67/006

  by elimination of segments of the precursor, e.g. nucleation-track membranes, lithography or laser methods · CPC title

• B01D69/08

  Hollow fibre membranes (manufacture of hollow fibres D01D5/24, D01F1/08) · CPC title