Patent attributes
An ion-conducting, sulfonated and crosslinked copolymer for use in a fuel cell is disclosed. The ion-conducting, sulfonated and crosslinked copolymer is made up of four monomers. The first monomer is an aromatic diol. The second monomer includes two groups, each group capable of reacting with the hydroxy groups of the first monomer, and each group independently selected from a nitro group and a halogen group. The third monomer is one of the first monomer or the second monomer, except that one of the hydrogen atoms attached to a benzene ring is substituted with —SO3Y, where Y is selected from hydrogen (H), lithium (Li), sodium (Na), potassium (K) and trialkyl ammonium of the form HNR3 where R is an alkyl group having from 1 to 5 carbon atoms. The fourth monomer includes at least three groups, each independently selected from a hydroxy group, a nitro group, and a halogen group.