Synthesis Of A Novel Sulfonated Poly (Arylene Ether Sulfone)s For Proton Exchange Membrane

Proton exchange membrane fuel cells(PEMFC) are promising power sources, since they offer a highly efficient and environment friendly solution for energy conversion. Polymer electrolyte membrane (PEM) is one of the most important integral parts of PEMFC. Membranes currently used in PEMFC are perfluorinated polymers such as Dupont Nafion. Even though it has demonstrated good performances and long-term stability, Nafion has three technical limitations in terms of high cost, low conductivity at low humidity or high temperature, and high methanol permeability, which could decrease the cell efficiency. As a consequence, a major research goal would be to identify and achieve novel, high performance ,low cost proton conductive electrolytes. Many engineering thermoplastic polymers such as polysulfones, polyethersulfone polyetherketones polyimide and so on have been claimed to be possible substitutes of perfluorinated ionomers, new PEMS for fuel cells are being explored.Poly(arylene ether sulfone)s have gained highly attention as high performance engineering thermal plastic, due to their good solvents resistance, good mechanical properties and high-thermal oxidative stability. Thus sulfonated PAESs are of interest as PEMs. In this paper a novel sulfonated poly(ether ether sulfone) derived from 3,3', 5,5'-Tetramethydephenyl-4,4'-Diol was synthesized by directly aromatic nuelecphilic condensation of 3,3',5,5'-tetrmethyl diphenyl-4,4'-diol with various ratios of 3,3'-disulfonate-4,4'-dichlorodiphenylsulfone to 4,4'-dichlorodiphenylsulfone. They shown good thermal stability, good solubility. Most of the polymers can be cast into tough membranes, and the properties of the membranes will further researched in future.