HYDROPHILIC EXPANDED FLUOROPOLYMER COMPOSITE AND METHOD OF MAKING SAME
A hydrophilic expanded fluoropolymer membrane having a coating comprising a copolymer comprising a non-wetting monomer and a fluoromonomer is described. In one embodiment, the non-wetting monomer and fluoromonomer are cross linked. A process of vaporizing, condensing and curing a formulation or formulations comprising the non-wetting monomer and/or the fluoromonomer is described. In one embodiment the condensed formulation is exposed to a high energy source such as a UV lamp for example to cross link the non-wetting monomer with the fluoromonomer. The coating may be conformable coating and may provide a hydrophilic membrane that has high water flow rates.
1 . An article comprising:
a. an expanded fluoropolymer;
b. a coating on the expanded fluoropolymer, wherein the coating comprises a copolymer formed from the cross-linking of at least one non-wetting hydrophilic monomer with at least one fluoromonomer to form the coating on the expanded fluoropolymer.
2 . The article of claim 1 , wherein the expanded fluoropolymer is expanded PTFE.
3 . The article of claim 1 , wherein the copolymer comprises fluoroacrylate.
4 . The article of claim 1 wherein the copolymer comprises perfluoroacrylate.
5 . The article of claim 1 , wherein the copolymer comprises perfluoroalkyl-2-hydroxypropylmethacrylate.
6 . The article of claim 1 , wherein the non wetting monomer comprises a hydrophilic monomer.
7 . The article of claim 1 , wherein the article is hydrophilic.
8 . The article of claim 1 , wherein the copolymer comprises a carboxylic group.
9 . The article of claim 1 , wherein the copolymer comprises an acrylic acid co-polymer.
10 . The article of claim 1 , wherein the copolymer comprises a non wetting monomer having a surface energy of at least 8 dynes/cm greater than the expanded fluoropolymer.
11 . The article of claim 1 , wherein the coating is a conformable coating.
12 . The article of claim 3 , wherein the hydrophilic monomer is copolymerized and cross-linked to a fluoroacrylate monomer.
13 . The article of claim 12 , wherein the hydrophilic monomer is cross-linked to the fluoromonomer with a multifunctional acrylate.
14 . The article of claim 1 , wherein the copolymer comprises a hydroxyl group.
15 . The article of claim 1 , wherein the copolymer comprises an amino group.
16 . The article of claim 1 , wherein the copolymer comprises a phosphonic group.
17 . The article of claim 1 , wherein the copolymer comprises a sulfonic group.
18 . The article of claim 1 having a BET surface area greater than 10 m 2 /g.
19 . The article of claim 1 , wherein the expanded fluoropolymer is a sheet having a first surface and a second surface.
20 . The article of claim 19 , wherein the sheet has a thickness greater than 20 um.
21 . The article of claim 20 wherein the both the first and second surfaces are hydrophilic.
22 . The article of claim 1 in the form of a tube, rod, or fiber.
23 . An article comprising:
a. an expanded fluoropolymer;
b. a coating on the expanded fluoropolymer,
wherein the coating comprises a copolymer formed from the evaporation, condensation and subsequent cross-linking of at least one non-wetting monomer with at least one fluoromonomer to form the coating on the expanded fluoropolymer.
24 . The article of claim 23 wherein the fluoromonomer and non-wetting monomer are evaporated and condensed simultaneously.
25 . The article of claim 23 wherein the article is hydrophilic.
26 . The article of claim 23 wherein non-wetting monomer is cross-linked to the perfluoroacrylate monomer by exposure to a high energy source.
27 . The article of claim 26 wherein the high energy source comprises ultraviolet light.
28 . The article of claim 23 wherein a cross-linking monomer is evaporated and condensed onto the expanded fluoropolymer.
29 . The article of claim 23 wherein the non-wetting monomer is cross-linked to the fluoromonomer.
30 . The article of claim 23 wherein a cross-linking monomer, fluoromonomer and non-wetting monomer are evaporated and condensed simultaneously.
31 . The article of claim 30 wherein the cross-linking monomer is a multifunctional acrylate.
32 . The article of claim 23 wherein the coating is a conformable coating.
32 . The article of claim 23 in the form of a tube, rod, or fiber.
33 . The article of claim 23 , wherein the copolymer comprises a hydroxyl group.
34 . The article of claim 23 , wherein the copolymer comprises an amino group.
35 . The article of claim 23 , wherein the copolymer comprises a phosphonic group.
36 . The article of claim 23 , wherein the copolymer comprises a sulfonic group.
37 . The article of claim 23 , wherein the copolymer comprises a carboxylic group.
38 . The article of claim 23 , wherein the copolymer comprises an acrylic acid co-polymer.