The sulfonated poly(phenylene) membranes containing multi-phenylrings prepared by nickel catalyst

• We synthesized sulfonated polyphenylene containing multi-phenyl moiety.
• We controlled by amount of chlorosulfuric acid and the time.
• Dimensional stabilities had punctuational values in spite of high IEC.
• Membranes showed good morphology with high proton conductivity.

The poly(phenylene)s containing multi-pendant phenyl were prepared by Ni-catalyzed reaction of 1,2-bis(4-chlorobenzoyl)-3,4,5,6-tetraphenylbenzene and 1,4-dichloro-2,5-dibenzoylbenzene. 1,4-Dichloro-2,5-dibenzoylbenzene is very reactive moiety to increase high molecular weight. These polymers without any ether linkages on polymer backbone were presumably stable against nucleophilic attack by hydrogen peroxide, hydroxide anion, and radical generated in PEMFC operation system. The phenyl rings on side chain were selectively sulfonated, but phenyl rings on main chain were deactivated by strong electron-withdrawing groups and steric hindrance. The structure of membranes was studied by 1H NMR spectroscopy and properties were measured by ion exchange capacity, water uptake, Fenton test and proton conductivity.

The poly(phenylene)s containing multi-pendant phenyl were prepared by Ni-catalyzed carbon-carbon coupling reaction of 1,2-bis(4-chlorobenzoyl)-3,4,5,6-tetraphenylbenzene and 1,4-dichloro-2,5-dibenzoylbenzene. The results of SPPTBP membranes were Δt values of 18.4%, 23.3%, and 51.3%, and Δl values of 0%, 0%, and 11.6%, respectively. Moreover it was shown the conductivities of 90.3, 120.2, and 134.2 mS/cm at 80 °C with relative humidity (90%). However SPPTBP membranes were clearly indicated low conductivity at 50% RH compared with Nafion 211®. Specially, the membrane of SPPTBP20b represented the meaningful results, which have high conductivity, low dimensional stability in comparison with that of Nafion 211®.Figure optionsDownload as PowerPoint slide