Electrolyte membrane, methods of manufacture thereof and articles comprising the same
View Patent ↗Disclosed herein is a method of forming an electrolyte membrane comprising forming a mixture; the mixture comprising a polyhydroxy compound, an aromatic polyhalide compound and an alkali metal hydroxide; disposing the mixture on a porous substrate; reacting the mixture to form a proton conductor; and crosslinking the proton conductor to form a cross-linked proton-conducting network. Disclosed herein too is an article comprising a porous substrate; and a crosslinked proton conductor disposed on the porous substrate.
1. A method of forming an electrolyte membrane comprising:
a forming a mixture; the mixture comprising a polyhydroxy compound,
a an aromatic polyhalide compound and an alkali metal hydroxide;
a disposing the mixture on a porous substrate;
a reacting the mixture to form a proton conductor; and
crosslinking the proton conductor to form a cross-linked proton-conducting network.
2. The method of claim 1 , wherein the aromatic polyhalide compound is an aromatic sulfonated dihalide.
3. The method of claim 1 , wherein the polyhydroxy compound is a compound having a structure shown in Formula (I):
wherein B is a hydrogen, alkyl, aryl or a protonic acid containing group; the protonic acid group being a sulfonate group (—SO 3 H), a carboxylate group (—COOH), a phosphate group (—PO 3 H 2 ), an alkylsulfonate group —(R 4 ) n SO 3 H), a sulfamoylsulfonylalkyl group or a sulfamoylsulfonylaryl group (—SO 2 NHSO 2 R) where R is alkyl or aryl, a perfloruoalkylsulfonate group (CF 2 ) n SO 3 H), a sulfonylalkylsulfonate group (SO 2 (R 4 ) n SO 3 H), a sulfonylperfluoroalkylsulfonate group (SO 2 (CF 2 )SO 3 H), a sulfamoylsulfonylalkylsulfonate group (SO 2 NHSO 2 (R 4 ) n SO 3 H), a sulfamoylsulfonylperfluoroalkylsulfonate group (SO 2 NHSO 2 (CF 2 ) n SO 3 H), an alkylcarboxylate group (—(R 4 ) n COOH), a perfluoroalkylcarboxylate group (CF 2 ) n CO 2 H an alkylphosphonate group (—(R 4 ) n PO 3 H 2 ), a perfluoroalkylphoshonate group or their conjugated salts; the conjugated salts having a metal cation; R 1 and R 2 are each independently a hydrogen atom, a halogen atom, a C 1-10 alkyl group, a halogen-substituted C 1-10 alkyl group, a C 6-50 aryl group; q and r are independently integers from 1 to about 4; R 3 is a hydrogen atom, a halogen atom, a C 1-10 alkyl group, a halogen-substituted C 1-10 alkyl group, a C 6-50 aryl group, or a halogen-substituted C 6-50 aryl group, while R 4 is an alkyl, aryl or perfluoroalkyl group, X is O, S, or SO 2 , and W is selected from the group consisting of
wherein R c and R d each independently represent a hydrogen atom or a monovalent linear or cyclic hydrocarbon group, and R e is a divalent hydrocarbon group, oxygen, or sulfur.
4. The method of claim 1 , wherein the polyhydroxy compound has a structure shown in Formula (II) below:
where R 5 , R 6 R 7 and R 8 are each independently a hydrogen atom, a halogen atom, a C 1-10 alkyl group, a halogen-substituted C 1-10 alkyl group, a C 6-50 aryl group or a halogen-substituted C 6-50 aryl group, and n, o and p are each independently integers of 1 to about 4.
5. The method of claim 1 , wherein the aromatic polyhalide compound has a structure shown in Formula (III):
where X is a halogen, R 9 and R 10 are each independently a hydrogen atom, a halogen atom, a C 1-10 alkyl group, a halogen-substituted C 1-10 alkyl group, a C 6-10 aryl group, or a halogen-substituted C 6-10 aryl group, s and t are each independently integers of 1 to 4, R 11 represents one of the following groups
and C is a protonic acid containing group; the protonic acid containing group being a sulfonate group (—SO 3 H), a carboxylate group (—COOH), a phosphate group (—PO 3 H 2 ), an alkylsulfonate group (—(R 12 ) n SO 3 H), a sulfamoylsulfonylalkyl or sulfamoylsulfonylaryl group (—SO 2 NHSO 2 R), wherein R is alkyl or aryl), a perfloruoalkylsulfonate group (CF 2 ) n SO 3 H), a sulfonylalkylsulfonate group (SO 2 (R 12 ) n SO 3 H), a sulfonylperfluoroalkylsulfonate group (SO 2 (CF 2 )SO 3 H), a sulfamoylsulfonylalkylsulfonate group (SO 2 NHSO 2 (R 12 ) n SO 3 H), a sulfamoylsulfonylperfluoroalkylsulfonate group (SO 2 NHSO 2 (CF 2 ) n SO 3 H), an alkylcarboxylate group (—(R 12 ) n COOH), a perfluoroalkylcarboxylate group (CF 2 ) n CO 2 H, an alkylphosphonate group (—(R 12 ) n PO 3 H 2 ), an perfluoroalkylphoshonate group or their conjugated salts; the conjugated salts having a metal cation and wherein R 12 can be an alkyl, aryl or perfluoroalkyl group.
6. The method of claim 1 , wherein the aromatic polyhalide compound has the structure shown in Formula (IV):
where X is a halogen and R 13 and R 14 are each independently a hydrogen atom, a halogen atom, a C 1-10 alkyl group, a halogen-substituted C 1-10 alkyl group, a C 6-10 aryl group, or a halogen-substituted C 6-10 aryl group; q and r are each independently integers of 1 to 3, R 15 represents one of the following groups:
wherein R c and R d each independently represent a hydrogen atom or a monovalent linear or cyclic hydrocarbon group, and R e is a divalent hydrocarbon group, oxygen, or sulfur, q and r are each independently integers of 1 to 3, M represents a metal cation from Group I.
7. The method of claim 6 , wherein R 13 and R 14 are each independently a hydrogen atom or a halogen atom, M is sodium, X is fluorine, and q and r are each independently integers of 1 to 3.
8. The method of claim 1 , wherein the alkali metal hydroxide is potassium hydroxide.
9. The method of claim 1 , further comprising adding a first solvent to the mixture.
10. The method of claim 9 , wherein the first solvent is water, an organic solvent or a combination comprising water and an organic solvent.
11. The method of claim 9 , further comprising adding a second solvent to the mixture, wherein the second solvent is an alcohol, water, liquid carbon dioxide, an aldehyde, a ketone, acetonitrile, a sulfoxide, a sulfone, a thiophene, an acetate, an amide, or a combination comprising at least one of the foregoing solvents.
12. The method of claim 11 , wherein the second solvent is isopropyl alcohol, dimethylsulfoxide, or a combination comprising at least one of the foregoing solvents.
13. The method of claim 1 , wherein the porous substrate is a polyolefin, a polyamide, a polycarbonate, a cellulosic polymer, a polyurethane, a polyester, a polyether, a polyacrylate, a copolyether ester, a copolyether amide, a fluoropolymer, or a combinations comprising at least one of the foregoing polymers.
14. The composition of claim 1 , wherein the porous substrate comprises a fluoropolymer; the fluoropolymer being a polytetrafluoroethylene, a poly(vinylidene fluoride), a poly(vinylidene fluoride co-hexafluoropropylene), a poly(tetrafluoroethylene oxide-co-difluoromethylene oxide, a poly(tetrafluoroethylene-co-perfluoro(propylvinyl ether)), or a combination comprising at least one of the foregoing fluoropolymers.
15. The composition of claim 14 , wherein the fluoropolymer is expanded polytetrafluoroethylene.
16. The method of claim 1 , further comprising reacting the mixture to form a proton conductor before disposing the mixture on the porous substrate.
17. The method of claim 1 , wherein the mixture is disposed by extrusion, brushing, spraying, transfer coating, or a combination comprising at least one of the foregoing coating methods.
18. The method of claim 1 , further comprising adding a dihydroxy compound to the mixture.
19. The method of claim 1 , wherein the dihydroxy compound is bisphenol A.
20. The method of claim 18 , wherein a weight ratio of the dihydroxy compound to the polyhydroxy compound is about 10:1 to about 1:10.
21. The method of claim 16 , wherein the electrolyte membrane comprises about 0.5 weight percent to about 50 weight percent proton conductor, based on the total weight of the electrolyte membrane.