Claims
- 1. An article having a surface, comprising an entangled blend of a first, relatively lower-cohesive-energy polymer component and a second, relatively higher-cohesive-energy polymer component that is compatible with the first polymer component at room temperature, the second polymer component present at the surface of the article in a ratio to the first polymer that is greater than the overall ratio in the article of the second polymer component to the first polymer component.
- 2. An article having a surface, comprising an entangled blend of a first, essentially hydrophobic polymer component and a second polymer component that is a random copolymer entangled with the first polymer component that is more hydrophilic than the first polymer component, the second polymer component having a molecular weight of at least about 15,000 and being present at the surface of the article in a ratio to the first polymer component that is greater than the overall ratio in the article of the second polymer component to the first polymer component.
- 3. An article having a surface, comprising an entangled blend of a first polymer having an affinity to water and a second polymer having an affinity to water, compatible with the first polymer at room temperature, the surface of the article having an affinity to water that is greater than the average water affinity of the total of the first and second polymers in the article.
- 4. An article as any preceding claim, the article defining a porous membrane.
- 5. An article as in any preceding claim, wherein the first polymer component is a relatively lower-cohesive-energy polymer component and the second polymer component is a relatively higher-cohesive-energy polymer component.
- 6. An article as in any preceding claim, wherein the first polymer component is essentially hydrophobic and the second polymer component is more hydrophilic than that first polymer component.
- 7. An article as in any preceding claim, wherein each of the first polymer component and the second polymer component has an affinity to water, and the surface of the article has an affinity to water that is greater than the average water affinity of the total of the first and second polymers in the article.
- 8. An article as in any preceding claim, wherein the second polymer component is present at the surface of the article in a ratio to the first polymer component that is greater than the overall ratio in the article of the first polymer component to the second polymer component.
- 9. An article as in any preceding claim, wherein at least the second polymer component is an acrylic polymer.
- 10. An article as in any preceding claim, wherein each of the first and second polymer components is an acrylic polymer.
- 11. An article as in any preceding claim, wherein each of the first and second polymer components is insoluble in water.
- 12. A method comprising providing a miscible blend of at least first and second polymer components each insoluble in water, the first component being essentially hydrophobic and the second component being more hydrophilic than the first component, and allowing the components to phase segregate to form a porous membrane having a core, and a surface of greater hydrophilicity than the core.
- 13. A method comprising:
providing a fluid blend of a first, relatively lower-cohesive-energy polymer component and a second, relatively higher-cohesive-energy polymer component that is compatible with the first polymer component at room temperature; and allowing the blend to harden to form a polymeric article having a surface, the second polymer component present at the surface of the article in a ratio to the first polymer component that is greater than the overall ratio in the article of the second polymer component to the first polymer component.
- 14. A method of making a polymer membrane having a particular surface chemical functionality, comprising:
providing a polymeric fluid comprising a blend of a first polymer component and a second polymer component that is compatible with the first polymer component at room temperature and that includes a particular chemical functionality; subjecting the polymeric fluid to phase inversion and recovering an article comprising the blend of the first and second polymer with the second polymer present at the surface of the article in a ratio to the first polymer that is greater than the overall ratio in the article of the second polymer to the first polymer.
- 15. A method of making a polymer membrane having a particular surface chemical functionality, comprising:
providing a polymeric fluid comprising a blend of a first polymer component and a second polymer component that is compatible with the first polymer component at room temperature; forming an emulsion by exposing the polymeric fluid to a fluid incompatible with the first and second components and allowing the incompatible fluid to form the emulsion in the polymeric fluid; and recovering from the mixture a porous article comprising the blend of the first and second polymer with the second polymer present at the surface of the article in a ratio to the first polymer that is greater than the overall ratio in the article of the second polymer to the first polymer.
- 16. A method as in either of claims 14 or 15, involving recovering a porous article comprising the blend of the first and second polymer with the second polymer present at the surface of the article in a ratio to the first polymer that is greater than the overall ratio in the article of the first polymer to the second polymer.
- 17. A method as in any of claims 12-16, wherein the article is a porous membrane.
- 18. A method as in any of claims claim 12-17, involving allowing the second polymer component to be entropically driven to the surface.
- 19. A method as in any of claims claim 12-18, wherein the first polymer component is a relatively lower-cohesive-energy polymer component and the second polymer component is a relatively higher-cohesive-energy polymer component.
- 20. A method as in any of claims claim 12-19, wherein the first polymer component is essentially hydrophobic and the second polymer component is more hydrophilic than that first polymer component.
- 21. A method as in any of claims claim 12-20, wherein each of the first polymer component and the second polymer component has an affinity to water, and the surface of the article has an affinity to water that is greater than the average water affinity of the total of the first and second polymers in the article.
- 22. A method as in any of claims claim 12-21, wherein the second polymer component is present at the surface of the article in a ratio to the first polymer component that is greater than the overall ratio in the article of the second polymer component to the first polymer component.
- 23. A method as in any of claims claim 12-22, wherein at least the second polymer component is an acrylic polymer.
- 24. A method as in any of claims claim 12-23, wherein each of the first and second polymer components is an acrylic polymer.
- 25. A method as in any of claims claim 12-24, wherein each of the first and second polymer components is insoluble in water.
- 26. An article or method as in any preceding claim, wherein the second polymer component has a polyionic functionality.
- 27. An article or method as in any preceding claim, wherein the second polymer component has a chelating functionality.
- 28. An article or method as in any preceding claim, wherein the second polymer component is more highly branched than the first polymer component.
- 29. An article or method as in any preceding claim, wherein the first polymer component is PVDF.
- 30. An article or method as in any preceding claim, wherein the first polymer component is PMMA.
- 31. An article or method as in any preceding claim, wherein the second polymer component is P(MMA-r-MnG).
RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 09/258,526, filed Feb. 26, 1999, which is a continuation-in-part of International Patent Application Serial No. PCT/US97/16488, filed Aug. 26, 1997, which is a PCT of U.S. patent application Ser. No. 08/819,610, filed Mar. 17, 1997 and U.S. Provisional Patent Application Serial No. 60/024,579.
Provisional Applications (2)
|
Number |
Date |
Country |
|
08819610 |
Mar 1997 |
US |
|
60024579 |
Aug 1996 |
US |
Continuations (1)
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Number |
Date |
Country |
Parent |
09258526 |
Feb 1999 |
US |
Child |
10007687 |
Dec 2001 |
US |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
PCT/US97/16488 |
Aug 1997 |
US |
Child |
09258526 |
Feb 1999 |
US |