Modified membranes
View Patent ↗A porous polymeric membrane formed from a blend of a polymeric membrane forming material, such as polyvinylidene fluoride or polysulfone and a polymeric reactivity modifying agent adapted to modify the surface active properties of the porous polymeric membrane. The reactivity modifying agent is preferably a linear polymeric anhydride, such as poly(alkyl vinyl ether/maleic anhydride). The surface activity modifications include modification of the hydrophilicity/hydrophobicity balance of the membrane, or hydrolysis followed by reaction with a polyamine to form a crosslinked polyamide layer. Such modified membranes have use as reverse osmosis membranes.
1. A microporous polymeric membrane comprising a blend of a polymeric anhydride ad a polymeric material comprising a polysulfone, said microporous membrane comprises surface anhydride sites reacted with amines forming amide in linkages by crosslinking.
2. The microporous polymeric membrane according to claim 1 , wherein the polysulfone comprises a material selected from the group consisting of polysulfone, polyether sulfone, polyaryl sulfone, polyalkyl sulfone, and polyaralkyl sulfone.
3. The microporous polymeric membrane according to claim 1 , wherein the polysulfone comprises polyphenyl sulfone.
4. The microporous polymeric membrane according to claim 1 , wherein the polymeric anhydride modifies a reactivity of a membrane surface to a chemical species.
5. The microporous polymeric membrane according to claim 1 , wherein the polymeric anhydride modifies a hydrophilicity/hydrophobicity balance of the microporous polymeric membrane.
6. The microporous polymeric membrane according to claim 1 , wherein the polymeric anhydride modifies a surface charge of the microporous polymeric membrane.
7. The microporous polymeric membrane according to claim 1 , wherein the polymeric anhydride comprises a linear polymeric anhydride.
8. The microporous polymeric membrane according to claim 1 , wherein the polymeric anhydride comprises a maleic anhydride copolymer.
9. The microporous polymeric membrane according to claim 1 , wherein the polymeric anhydride comprises a poly(alkyl vinyl ether/maleic anhydride).
10. The microporous polymeric membrane according to claim 1 , wherein the polymeric anyhydride has a formula:
11. The microporous polymeric membrane according to claim 1 , wherein the polymeric anhydride comprises poly(methyl vinyl ether/maleic anhydride) having a molecular weight of from 5×10 4 to 5×10 7 .
12. The microporous polymeric membrane according to claim 11 , wherein the polymeric anhydride comprises poly(methyl vinyl ether/maleic anhydride) having a molecular weight of from 2.13×10 5 to 1.89×10 6 .
13. The microporous polymeric membrane according to claim 12 , wherein the polymeric anhydride comprises poly(methyl vinyl ether/maleic anhydride) having a molecular weight of from 8.72×10 5 to 1.25×10 6 .
14. The microporous polymeric membrane according to claim 1 , wherein there is a negative charge on a surface of the microporous polymeric membrane.
15. The microporous polymeric membrane according to claim 1 , wherein the membrane is a shape selected from the group consisting of a hollow fibre and a flat sheet.
16. The microporous polymeric membrane according to claim 1 , wherein the membrane has a uniform wall thickness.