Hydrophilic membranes

Patent metadata

Field	Value
Publication number	US-2023017950-A1
Application number	US-202017778663-A
Country	US
Kind code	A1
Filing date	Nov 18, 2020
Priority date	Nov 21, 2019
Publication date	Jan 19, 2023
Grant date	—

Abstract

The present application relates to an unsupported, permanently hydrophilic filtration membrane, and its method of formation. The membrane comprises a polymeric matrix material and a cross-linked polyoxazoline hydrophilic additive blended throughout said matrix material.

First claim

What is claimed:

1 . An unsupported, permanently hydrophilic filtration membrane comprising:
a polymeric matrix material and a cross-linked polyoxazoline hydrophilic additive blended throughout said matrix material.

2 . The permanently hydrophilic filtration membrane of claim 1 , wherein the membrane is a microporous membrane.

3 . The permanently hydrophilic filtration membrane of claim 1 , wherein the membrane is an ultrafiltration membrane.

4 . The permanently hydrophilic filtration membrane of claim 1 , wherein the extractable total organic carbon of the permanently hydrophilic filtration membrane is less than 20 μgC/cm 2 .

5 . The permanently hydrophilic filtration membrane of claim 1 , wherein the extractable total organic carbon of the permanently hydrophilic filtration membrane is less than 10 μgC/cm 2 .

6 . The permanently hydrophilic filtration membrane of claim 1 , wherein the polyoxazoline is selected from the group consisting of poly (2-ethyl-2-oxazoline), poly(2-methyl-2-oxazoline), and poly(2-propyl-2-oxazoline).

7 . The permanently hydrophilic filtration membrane of claim 6 , wherein the polyoxazoline is poly (2-ethyl-2-oxazoline).

8 . The permanently hydrophilic filtration membrane of claim 1 , wherein the polyoxazoline is cross-linked by electron beam with a dose of from about 20 to 150 kGy.

9 . The permanently hydrophilic filtration membrane of claim 1 , wherein the polymeric matrix material is one or more polymers independently selected from the group consisting of PVDF, polyamides, polyimides, polyether sulphones, polysulphones, polyaryl sulphones, cellulose esters, polyetherimides, acrylic polymers, methacrylic polymers, and copolymers of acrylic and methacrylic polymers.

10 . The permanently hydrophilic filtration membrane of claim 1 , wherein the membrane comprises polyether sulfone and poly (2-ethyl-2-oxazoline).

11 . The permanently hydrophilic filtration membrane of claim 1 , wherein the membrane is symmetric.

12 . The permanently hydrophilic filtration membrane of claim 1 , wherein the membrane is asymmetric.

13 . The permanently hydrophilic filtration membrane of claim 1 , wherein the membrane has a breaking strain of at least 20%.

14 . The permanently hydrophilic filtration membrane of claim 1 , wherein the membrane has a breaking strain of at least 25%.

15 . The permanently hydrophilic filtration membrane of claim 1 , wherein the membrane has a breaking strain of at least 30%.

16 . The permanently hydrophilic filtration membrane of claim 1 , wherein the membrane has one or more distinct zones.

17 . The permanently hydrophilic filtration membrane of claim 16 , wherein the membrane has three distinct zones.

18 . The permanently hydrophilic filtration membrane of claim 1 , wherein the membrane has a total thickness from about 65 to 300 μm.

19 . The permanently hydrophilic filtration membrane of claim 1 , wherein the membrane is pleated.

20 . A filtration cartridge comprising:
a housing; and the membrane of claim 1 positioned within the housing.

21 . The cartridge of claim 20 , wherein the membrane has an extractable total organic carbon less than 20 μgC/cm 2 .

22 . The cartridge of claim 21 , wherein the membrane has an extractable total organic carbon less than 10 μgC/cm 2 .

23 . The cartridge of claim 20 , wherein the polyoxazoline is selected from the group consisting of poly (2-ethyl-2-oxazoline), poly(2-methyl-2-oxazoline), and poly(2-propyl-2-oxazoline).

24 . The cartridge of claim 23 , wherein the polyoxazoline is poly (2-ethyl-2-oxazoline).

25 . The cartridge of claim 20 , wherein the polyoxazoline is cross-linked by electron beam with a dose of from about 20 to 150 kGy.

26 . The cartridge of claim 20 , wherein the polymeric matrix material is one or more polymers independently selected from the group consisting of PVDF, polyamides, polyimides, polyether sulphones, polysulphones, polyaryl sulphones, cellulose esters, polyetherimides, acrylic polymers, methacrylic polymers, and copolymers of acrylic and methacrylic polymers.

27 . The cartridge of claim 20 , wherein the membrane comprises polyether sulfone and poly (2-ethyl-2-oxazoline).

28 . The cartridge of claim 20 , wherein the membrane has a breaking strain of greater than 20%.

29 . The cartridge of claim 28 , wherein the membrane has a breaking strain of greater than 25%.

30 . The cartridge of claim 29 , wherein the membrane has a breaking strain of greater than 30%.

31 . The filtration cartridge of claim 20 , wherein the housing contains greater than 0.11 m 2 of effective membrane area per 1 inch of housing height.

32 . A process of forming a permanently hydrophilic filtration membrane comprising:
providing one or more casting solutions of a polymer comprising polyoxazoline and a solvent for said polymer; simultaneously or sequentially applying the casting solution or solutions onto a support to form a liquid sheet; effecting, in the liquid sheet, a phase separation of the casting solution or solutions to form a membrane; immersing the membrane with water or an aqueous solution; treating the wet membrane with an electron beam to crosslink the polyoxazoline; and separating the permanently hydrophilic filtration membrane from the support.

33 . The process of claim 32 , wherein the aqueous solution is selected from a mixture of mixture of water and multi-functional monomer or monomers.

34 . The process of claim 33 , wherein the monomer or monomers are methylene bis-acrylamide, Sartomer 9035, Tetra(ethylene glycol) diacrylate, and mixtures thereof.

35 . The process of claim 33 , wherein the membranes extractable total organic carbon is less than 20 μgC/cm 2 .

36 . The process of claim 35 , wherein the membranes extractable total organic carbon is less than 10 μgC/cm 2 .

37 . The process of claim 32 , wherein the polyoxazoline is selected from the group consisting of poly (2-ethyl-2-oxazoline), poly(2-methyl-2-oxazoline), and poly(2-propyl-2-oxazoline).

38 . The process of claim 37 , wherein the polyoxazoline is poly (2-ethyl-2-oxazoline).

39 . The process of claim 32 , wherein the polyoxazoline is cross-linked by electron beam with a dose of from about 20 to 150 kGy.

40 . The process of claim 32 , wherein the casting solution comprises polyether sulfone, N-methyl-2-pyrrolidone, triethylene glycol, and poly (2-ethyl-2-oxazoline).

41 . The process of claim 32 , wherein the membrane has a breaking strain of greater than 20%.

42 . The process of claim 41 , wherein the membrane has a breaking strain of greater than 25%.

43 . The process of claim 42 , wherein the membrane has a breaking strain of greater than 30%.

44 . The process of claim 32 , wherein said polymer is one or more polymers independently selected from the group consisting of PVDF, polyamides, polyimides, polyether sulphones, polysulphones, polyaryl sulphones, cellulose esters, polystyrenes, polyetherimides, acrylic polymers, methacrylic polymers, and copolymers of acrylic and methacrylic polymer

Assignees

• Emd Millipore Corp

Inventors

• Ge Jijun
• Zhou Xiaozhu
• Tkacik Gabriel

Classifications

• B01D2325/022

  Asymmetric membranes · CPC title

• B01D61/147

  Microfiltration · CPC title

• B01D2323/30

  Cross-linking · CPC title

• B01D71/68

  Polysulfones; Polyethersulfones · CPC title

• B01D61/145 Primary

  Ultrafiltration · CPC title