Block copolymers

• US 5,834,583 A
• Filed: 12/23/1997
• Issued: 11/10/1998
• Est. Priority Date: 07/27/1995
• Status: Expired due to Fees

• Current Assignee: CB Biomedical, Inc. (Arbios Systems, Inc.)
• Original Assignee: CB Biomedical, Inc. (Arbios Systems, Inc.)
• Inventors: Hancock, Lawrence Francis, Kishbaugh, Alan Jay, Parham, Marc Ellous
• Primary Examiner(s): Truong, Duc
• Application Number:
  US08/997,298
• Time in Patent Office: 322 Days
• Field of Search: 528/373, 528/499, 528/503, 525/88, 525/96, 521/50, 264/235
• US Class Current: 528/499
• CPC Class Codes: B01D 2325/022 Asymmetric membranes
• CPC Class Codes: B01D 2325/026 Sponge structure
• CPC Class Codes: B01D 2325/04 Characteristic thickness
• CPC Class Codes: B01D 2325/08 Patterned membranes
• CPC Class Codes: B01D 2325/36 Hydrophilic membranes
• CPC Class Codes: B01D 2325/38 Hydrophobic membranes
• CPC Class Codes: B01D 67/0011 Casting solutions therefor
• CPC Class Codes: B01D 67/00111 Polymer pretreatment in the casting solutions
• CPC Class Codes: B01D 67/0083 Thermal after-treatment
• CPC Class Codes: B01D 71/52 Polyethers
• CPC Class Codes: B01D 71/5211 Polyethylene glycol or polyethyleneoxide
• CPC Class Codes: B01D 71/68 Polysulfones; Polyethersulfones
• CPC Class Codes: B01D 71/80 Block polymers
• CPC Class Codes: C08G 65/3348 containing nitrogen in addition to sulfur
• CPC Class Codes: C08G 65/337 containing other elements organic compounds containing halogens only as halides of a carboxyl group C08G65/332
• CPC Class Codes: C08G 75/23 Polyethersulfones
• CPC Class Codes: C08J 2371/02 Polyalkylene oxides
• CPC Class Codes: C08J 9/28 by elimination of a liquid phase from a macromolecular composition or article, e.g. drying of coagulum
• CPC Class Codes: C08L 2205/05 containing polymer components which can react with one another
• CPC Class Codes: C08L 71/00 Compositions of polyethers obtained by reactions forming an ether link in the main chain of polyacetals C08L59/00; of epoxy resins C08L63/00; of polythioether-ethers C08L81/02; of polyether-sulfones C08L81/06; Compositions of derivatives of such polymers
• CPC Class Codes: C08L 71/02 : Polyalkylene oxides
• CPC Class Codes: C08L 81/00 : Compositions of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing sulfur with or without nitrogen, oxygen or carbon only; Compositions of polysulfones; Compositions of derivatives of such polymers
• CPC Class Codes: C08L 81/06 : Polysulfones; Polyethersulfones

Abstract

A poly(ethyleneoxy) block copolymer including a hydrophobic block segment useful in making a porous polymer article with improved surface hydrophilicity. Also disclosed is a method of making such a polymer article.

Claims

1. A method of making a porous polymer article with enhanced hydrophilicity comprising the steps of:

providing a casting solution which includes

(i) 0.1-50 weight percent of a block copolymer having the formula;

space="preserve" listing-type="equation">R--(OCH.sub.2 CH.sub.2).sub.n --X--Y (I)

wherein R is C_1-20 alkyl, C_7-20 alkylaryl, C_7-20 arylalkyl, or C_1-20 perfluoroalkyl;

n is between 20 and 500;

X is --Z¹ --(OAr¹ OAr²)_m -- or --(OAr² OAr¹)_m --; and

Y is hydroxy, --(OAr³ O)--Z² --(CH₂ CH₂ O)_p --R¹, or --(OAr⁴ O)--(CH₂ CH₂ O)_p --R¹ ;

in which Z¹ is selected from --N(R²)--(SO₂)--C₆ H₄ -- and --N(R²)--(C═

O)--C₆ H₄ --, R² being C_1-12 alkyl or C_6-20 aryl;

Z² is selected from --C₆ H₄ --(SO₂)--N(R³)-- and --C₆ H₄ --(C═

O)--N(R³)--, R³ being C_1-12 alkyl or C_6-20 aryl;

R¹ is C_1-20 alkyl, C_7-20 alkylaryl, C_7-20 arylalkyl, or C_1-20 perfluoroalkyl;

each of Ar¹ and Ar³ is independently selected from 1,4-phenylene, 1,3-phenylene, naphthyl-1,4-diyl, naphthyl-1,5-diyl, 4,4'"'"'-biphenylene, diphenyl ether-4,4'"'"'-diyl, diphenylthioether-4,4'"'"'-diyl, diphenylisopropylidene-4,4'"'"'-diyl, diphenylhexafluoroisopropylidene-4,4'"'"'-diyl, diphenylalkylene-4,4'"'"'-diyl wherein alkylene is --(CH₂)_q --, q being 1, 3, 5, 7 or 9, p-terphenyl-4,4'"'"'-diyl, and bivalent radicals of binaphthalene, anthracene, and phenylnaphthalene;

each of Ar² and Ar⁴ is independently selected from diphenylsulfoxide-4,4'"'"'-diyl, diphenylsulfone-4,4'"'"'-diyl, diphenyl ketone-4,4'"'"'-diyl, and bivalent radicals of diphenyl-C_1-12 alkyl phosphine oxide and diphenyl-C_6-20 aryl phosphine oxide;

m is between 1 and 250; and

p is between 20 and 500;

(ii) 0-40 weight percent of polysulfone; and

(iii) 40-95 weight percent of a polar aprotic solvent selected from N-methylpyrrolidinone, 4-butyro-lactone, dimethylsulfoxide, and dimethylformamide;

contacting said casting solution with a nonsolvent coagulation bath until a porous polymer article forms; and

thermally annealing said article in the presence of water to enhance the hydrophilicity of said article.

2. A method of claim 1, wherein the thermal annealing step includes heating said article at a temperature between 95°

and 130°

C.

3. A method of claim 1, wherein the thermal annealing step includes heating said article at a temperature between 40°

and 90°

C.

4. A method of claim 1, wherein the weight percent of said block copolymer in said casting solution is 5-35 weight percent.

5. A method of claim 1, wherein the weight percent of said polysulfone is 0.1-30 weight percent.

6. A method of claim 1, wherein said casting solution further includes 5-30 weight percent of a hydroxyl-containing reagent selected from polyethylene glycol, water, and C_1-8 alkanol.

7. A method of claim 1, wherein said casting solution includes:

10 weight percent block copolymer, 10 weight percent polysulfone, and 80 weight percent polar aprotic solvent;

10 weight percent block copolymer, 15 weight percent polysulfone, 25 weight percent polyethylene glycol, and 50 weight percent polar aprotic solvent;

or 15 weight percent block copolymer, 5 weight percent polysulfone, and 80 weight percent polar aprotic solvent.

8. A method of claim 1, wherein said polar aprotic solvent is N-methyl pyrrolidinone.