Sulfonated poly(phenylene) copolymer electrolyte for fuel cells

1. A proton conducting copolymer electrolyte comprising:

a proton conducting sulfonated poly(phenylene) hydrophilic domain; and

a hydrophobic domain comprising a main chain comprising a plurality of bonded arylene groups;

wherein essentially all of the bonds in the main chain of the copolymer electrolyte are carbon-carbon or carbon-sulfone bonds, and

wherein the structure of the hydrophilic domain is selected from the group consisting of:

wherein R3 is:

R2 is:

(CF 2 ) l SO 3 H; (CH 2 ) l SO 3 H;

l is an integer in the range from 0 to 10;

x is 3 or 4;

y is 3 or 4; and

m is an integer in the range from about 1 to 100.

2. The copolymer electrolyte of claim 1 wherein essentially all of the bonds in the main chain of the copolymer electrolyte are carbon-carbon bonds.

3. The copolymer electrolyte of claim 1 wherein essentially none of the bonds in the chains of the copolymer electrolyte are ether bonds.

4. The copolymer electrolyte of claim 1 wherein the structure of the hydrophobic domain is:

wherein e, f, g, and h are integers greater than or equal to zero, and at least one is greater than zero;

wherein —(Ar1) e - is:

R 4 is H, (CF 2 ) k CF 3 , or (CH 2 ) k CH 3 ,

k is an integer in the range from about 0 to 19, and

a is an integer in the range from about 1 to 5;

wherein —(Ar2) f - is:

R5=—; (CF 2 ) k ; (CH 2 ) k ;

and

k is in the range from about 0 to 19;

wherein —(Ar3) g - is:

R6 is H, NH 2 , CH 3 , or phenyl; and

R7 is H, NH 2 , CH 3 , or phenyl; and

wherein —(Ar4) h - is:

wherein r, s, t and u are positive integers and r+s=5 or 6, t+u=5 or 6, and s+u>=3 or

wherein r, s, t, u, v and w are positive integers and r+s=5 or 6, t+u=5 or 6, v+w=5 or 6, and s+u+w>=3;

R8 is:

R9 is:

R10 is:

l is an integer in the range from about 0 to 10; and

m and n are integers greater than or equal to zero and m+n=5 or 6, and n>=3.

5. The copolymer electrolyte of claim 1 wherein the structure of the hydrophilic domain is selected from the group consisting of:

6. The copolymer electrolyte of claim 4 wherein the structure of the hydrophobic domain is selected from the group consisting of:

wherein

n=3-6;

l is an integer in the range from about 0 to 10;

k is an integer in the range from about 0 to 19, and

wherein

n=3-6;

k is an integer in the range from about 0 to 19; and

n:x:y=5:1:1.

7. The copolymer electrolyte of claim 1 wherein the structure of the hydrophilic domain is:

and the structure of the hydrophobic domain is:

8. The copolymer electrolyte of claim 1 wherein the structure of the hydrophilic domain is:

and the structure of the hydrophobic domain is:

9. A membrane electrode assembly for a solid polymer electrolyte fuel cell comprising the copolymer electrolyte of claim 1 .

10. A solid polymer electrolyte fuel cell comprising the copolymer electrolyte of claim 1 .