| 초록 |
Perfluorinated sulfonic acid membranes such as Nafion are the most frequently used as the proton exchange membrane material due to their good proton conductivity, and excellent chemical and mechanical stabilities. But the direct use of the Nafion in the direct methanol fuel cell (DMFC) often causes poor fuel efficiency due to higher methanol permeability. In this research, Nafion surface was modified by layer by layer (LbL) self-assembly of both cationic and anionic polyelectrolyte materials. For the cationic polyelectrolyte, a polystyrene copolymer containing quaternary ammonium salt as well as azide moiety was prepared starting from copolymerization of styrene and vinylbenzyl chloride. For the anionic polyelectrolyte, highly sulfonated poly(phenylene oxide) (sPPO) was used. Prepared membranes were UV crosslinked, and characterized by H-NMR, IR, IEC, water uptake, proton conductivity, and methanol permeability. Pristine Nafion™ was used as a reference. |
