The invention provides ion-conductive copolymers that can be used to fabricate proton exchange membranes (PEM's), catalyst coated proton exchange membranes (CCM's) and membrane electrode assemblies (MEA's) which are useful in fuel cells and their application in electronic devices, power sources and vehicles. The ion-conductive copolymers comprise one or more ion-conductive oligomers randomly positioned in a polymeric backbone that is not ion-conductive.