Composition containing proton-conductive copolymer, polymer electrolyte membrane, method of producing the membrane , and fuel cell using the membrane

A polymer electrolyte membrane containing a composition comprising:

• a proton-conductive copolymer comprising a repeating unit represented by the following Formula (1), a repeating unit represented by the following Formula (2), and a repeating unit represented by the following Formula (3);
• and
• a cross-linked polymer obtained from a cross-linking reaction between a siloxane oligomer having an unsaturated bond and a cross-linking agent:
• wherein R1 and R2 are each independently selected from hydrogen, a halogen atom, or a halogenated C1-C10 alkyl group, and p represents a molar amount ranging from 0.1 to
• wherein R3 and R4 are each independently selected from hydrogen, a halogen atom, or a halogenated C1-C10 alkyl group, R5 represents —SO3H, —PO3H, or —CO2H, and q represents a molar amount ranging from 0.1 to 0.9;
• wherein R6 represents a C1-C10 alkyl group;
• and r represents a molar amount ranging from 0.1 to 0.9.

A method of producing a polymer electrolyte membrane, the method comprising:

• dissolving a proton-conductive copolymer comprising a repeating unit represented by the following Formula (1), a repeating unit represented by the following Formula (2), and a repeating unit represented by the following Formula (3), a siloxane oligomer having an unsaturated bond, and a cross-linking agent in a solvent;
• forming a film using the resulting solution;
• and
• heating the formed film to induce a cross-linking reaction between the siloxane oligomer having an unsaturated bond and the cross-linking agent:
• wherein R1 and R2 are each independently selected from hydrogen, a halogen atom, or a halogenated C1-C10 alkyl group, and p represents a molar amount ranging from 0.1 to 0.9;
• wherein R3 and R4 are each independently selected from a halogen atom, or a halogenated C1-C10 alkyl group, R5 represents —SO3H, —PO3H or —CO2H, and q represents a molar amount ranging from 0.1 to 0.9;
• wherein R6 represents a C1-C10 alkyl group;
• and r represents a molar amount ranging from 0.1 to 0.9.