Poly(aryl ether)s containing the diphenylethylene moiety, synthesized from 1,1-bis(4-fluorophenyl)ethylene or 1,1-bis(4-hydroxyphenyl)ethylene, are thermally crosslinkable. Characterization and crosslinking studies of these polymers were carried out by GPC, DSC, TGA, and NMR. The solvent resistance and T-g’s of the resulting crosslinked networks increase after crosslinking. Thermogravimetric analysis shows that no significant mass loss accompanies the crosslinking reaction.