Hydrophilically modified fluorinated membrane (I)

Patent metadata

Field	Value
Publication number	US-9636641-B2
Application number	US-201514675528-A
Country	US
Kind code	B2
Filing date	Mar 31, 2015
Priority date	Mar 31, 2015
Publication date	May 2, 2017
Grant date	May 2, 2017

Abstract

Disclosed are polymers suitable for hydrophilically modifying the surface of porous fluoropolymer supports, for example, a copolymer of the formula:

Also disclosed are a method of preparing the polymers, a method of hydrophilically modifying porous fluoropolymer supports, hydrophilic fluoropolymer porous membranes prepared from the polymers, and a method of filtering fluids through the porous membranes.

First claim

The invention claimed is:

1. A composite hydrophilic porous membrane comprising a porous fluoropolymer support and a coating comprising a copolymer, wherein the copolymer comprises repeat units A and B, wherein A is selected from

and B is of the formula:

wherein:
the copolymer is a block copolymer or a random copolymer; and
the number of repeat units of each of B and A are n and m, and range from 1 to about 1000, provided the sum of n and m is equal to or greater than 10,
wherein the copolymer is optionally crosslinked.

2. The composite hydrophilic porous membrane of claim 1 , wherein the copolymer has chain end groups selected from aryl groups and alkoxy groups.

3. The composite hydrophilic porous membrane of claim 1 , wherein the copolymer is of one of the following formulae:

4. The composite hydrophilic porous membrane of claim 1 , wherein the copolymer further comprises one or more repeat units C of the formula:

wherein the ratio o/(m+n) is from above 0 to about 0.25, o being the number of repeat units C comprised in the copolymer.

5. The composite hydrophilic porous membrane of claim 4 , wherein the copolymer is a random copolymer and is of the formula:

6. A method of hydrophilically modifying a porous fluoropolymer support comprising:
(i) providing a porous fluoropolymer support;
(ii) coating the porous fluoropolymer support with a solution comprising a solvent and copolymer wherein the copolymer comprises repeat units A and B, wherein A is selected from

and B is of the formula:

wherein:
the copolymer is a block copolymer or a random copolymer; and
the number of repeat units of each of B and A are n and m, and range from 1 to about 1000, provided the sum of n and m is equal to or greater than 10,
(iii) drying the coated fluoropolymer support from (ii) to remove at least some of the solvent from the solution comprising said copolymer or polymer; and optionally
(iv) crosslinking said copolymer or polymer present in the coated fluoropolymer support.

7. The method of claim 6 , wherein the copolymer has chain end groups selected from aryl groups and alkoxy groups.

8. The method of claim 6 , wherein the copolymer is of one of the following formulae:

9. The method of claim 6 , wherein the copolymer further comprises one or more repeat units C of the formula:

wherein the ratio o/(m+n) is from above 0 to about 0.25, o being the number of repeat units C comprised in the copolymer.

10. The method of claim 9 , wherein the copolymer is a random copolymer and is of the formula:

11. The method of claim 6 , wherein the crosslinking of the coating is carried by exposing the coating to UV radiation.

12. A hydrophilically modified porous fluoropolymer membrane produced by the method of claim 6 .

13. The hydrophilic porous membrane of claim 1 , wherein the porous fluoropolymer support is selected from PTFE, PVDF, PVF (polyvinyl fluoride), PCTFE (polychlorotrifluoroethylene), FEP (fluorinated ethylene-propylene), ETFE (polyethylenetetrafluoroethylene), ECTFE (poly ethylenechlorotrifluoroethylene), PFPE (perfluoropolyether), PFSA (perfluorosulfonic acid), and perfluoropolyoxetane.

Assignees

• Pall Corp

Inventors

• Aamer Khaled Abdel-Hakim Helmy
• Qiu Jian
• Ait-Haddou Hassan

Classifications

• C08J7/0427

  with only one layer of a composition containing a polymer binder (with more layers C08J7/042) · CPC title

• B01D2325/36

  Hydrophilic membranes · CPC title

• B01D71/32 Primary

  containing fluorine atoms · CPC title

• B01D2323/02

  Hydrophilization · CPC title

• C08J5/2237

  containing fluorine · CPC title