Proton-exchange membrane electrolytes derived from phosphonic acid containing poly(arylene ether)s

A novel phosphonic acid containing bisphenol was successfully synthesized from phenolphthalein and m-aminophenylphosphonic acid. Poly(arylene ether)s containing phosphonic acid groups were prepared from the bisphenol. This is the first report on the attachment of phenylphosphonic acid groups as side chains to aromatic polyethers. These polyethers had very high glass transition temperatures and molecular weights. The conductivities of the polyethers ranged from 10−5 to 10−6 S cm−1 and therefore show promise as proton-exchange polymer electrolyte membranes for fuel cells.