Cross-linked polyimide and method of making them
View Patent ↗A cross-linked polyimide is disclosed. The cross-linked polyimide includes a polyimide and at least one oxygenated hydrocarbon. The oxygenated hydrocarbon cross-links the polyimide. A porous cross-linked membrane is also disclosed. The porous cross-linked membrane includes a support structure and a cross-linked polyimide disposed on the support structure. The cross-linked polyimide includes a polyimide; and at least one oxygenated hydrocarbon cross-linking the polyimide. Also disclosed are methods of making the cross-linked polyimide and the porous cross-linked membrane.
1. A cross-linked polyimide comprising:
a polyimide; and
at least one oxygenated hydrocarbon cross-linking the polyimide, wherein the oxygenated hydrocarbon has an oxygen moiety
wherein the polyimide comprises a polyether imide, and wherein the polyether imide comprises a repeat unit comprising:
wherein the repeat unit comprises a finite number of repeat units.
2. The cross-linked polyimide of claim 1 , wherein the polyimide further comprises a repeat unit comprising:
wherein R is independently at each occurrence an alkyl group, or an aryl group; and
wherein the repeat unit comprises a finite number of repeat units, and “in” is a finite number in a range from about 1 to about 1000.
3. The cross-linked polyimide of claim 1 , wherein the oxygenated hydrocarbon comprises at least one oxygenated hydrocarbon selected from the group consisting of formals, ethers, acetals, ketals, orthoformates, thioorthoformate, ketones, aldehydes, and epoxides.
4. The cross-linked polyimide of claim 3 , wherein the oxygenated hydrocarbon comprises at least one oxygenated hydrocarbon selected from the group consisting formaldehyde, methylal, dioxolane, trioxane, tetraoxane, paraformaldehyde, trioxane, tetraoxane, dialkoxymethane, diacyloxymethane, 1,3-dioxane, 1,3-dithiane, 1,3-oxathianeacetaldehyde, propionaldehyde, butylaldehyde, iso-butylaldehyde, valeraldehyde, laurinaldehyde, stearinaldehyde, glyoxal, succindialdehyde, acrolein, crotonaldehyde, propiolaldehyde, benzaldehyde, tolylaldehyde, salicylaldehyde, cinnamaldehyde, naphthaldehyde, furfural, and glycidyl ether.
5. The cross-linked polyimide of claim 4 , wherein the oxygenated hydrocarbon comprises at least one oxygenated hydrocarbon selected from the group consisting of paraformaldehyde, formaldehyde, dioxolane, and trioxane.
6. The cross-linked polyimide of claim 1 , wherein the oxygenated hydrocarbon comprises a plurality of oxygenated hydrocarbons.
7. The cross-linked polyimide of claim 6 , wherein the plurality of oxygenated hydrocarbons cross-link the polyimide at a plurality of sites.
8. A method of making a cross-linked polyimide comprising:
providing a polyimide and providing an oxygenated hydrocarbon for cross-linking the polyimide, wherein the oxygenated hydrocarbon has an oxygen moiety,
wherein the polyimide comprises a polyether imide, and wherein the polyether imide comprises a repeat unit comprising:
wherein the repeat unit comprises a finite number of repeat units.
9. The method of claim 8 , wherein the polyimide further comprises a repeat unit comprising:
wherein R is independently at each occurrence an alkyl group, or an aryl group; and wherein the repeat unit comprises a finite number of repeat units, and “m” is a finite number in a range from about 1 to about 1000.
10. The method of claim 8 , wherein providing the oxygenated hydrocarbon occurs under the presence of a catalyst.
11. The method of claim 10 , wherein the catalyst comprises an acid.
12. The method of claim 11 , wherein the acid comprises at least one acid selected from the group consisting of sulfuric, phosphoric, sulfonic acid, and boron trifluoride.
13. The method of claim 12 , wherein the acid comprises sulfuric acid.
14. The method of claim 8 , wherein the oxygenated hydrocarbon comprises at least one oxygenated hydrocarbon selected from the group consisting of formals, ethers, acetals, ketals, orthoformates, thioorthoformate, ketones, aldehydes, and epoxides.
15. The method of claim 14 , wherein the oxygenated hydrocarbon comprises at least one oxygenated hydrocarbon selected from the group consisting formaldehyde, methylal, dioxolane, trioxane, tetraoxane, paraformaldehyde, trioxane, tetraoxane, dialkoxymethane, diacyloxymethane, 1,3-dioxane, 1,3-dithiane, 1,3-oxathianeacetaldehyde, propionaldehyde, butylaldehyde, iso-butylaldehyde, valeraldehyde, laurinaldehyde, stearinaldehyde, glyoxal, succindialdehyde, acrolein, crotonaldehyde, propiolaldehyde, benzaldehyde, tolylaldehyde, salicylaldehyde, cinnamaldehyde, naphthaldehyde, furfural, and glycidyl ether.
16. The method of claim 15 , wherein the oxygenated hydrocarbon comprises at least one oxygenated hydrocarbon selected from the group consisting of paraformaldehyde, formaldehyde, dioxolane, and trioxane.
17. The method of claim 8 , wherein the oxygenated hydrocarbon comprises a plurality of oxygenated hydrocarbons.
18. The method of claim 17 , wherein the plurality of oxygenated hydrocarbons cross-link the polyimide at a plurality of sites.