Ionomer membranes conductance

Dolye, M., Lewittes, M. E., Roelofs, M. G. and Perusich, S. A. 2001. Ionic conductivity of nonaqueous solvent-swoUen ionomer membranes based on fluorosulfonate, fluorocarboxylate, and sulfonate fixed ion groups. Journal of Physical Chemistry B 105 9387-9394. 

In the hydrated ionomer membrane, liquid-like water acts as the pore former, pore filler, and proton shuffle. The wafer disfribufion and the random network morphology of aqueous pafhways determine proton conduction at... 

The built-in and operation stresses are the consequences of the large swelling and shrinkage of the ionomer membrane when it uptakes and loses water. This is frequently referred to as dimensional instability in the literature. Water in the PFSA membrane is an essential ingredient of its proton conduction behavior. Water affects the morphology13,14 of the ionic clusters (at nanoscale) which... 

Early research of ionomer membrane degradation was conducted in the context of PEM electrolyzers. The detection of fluoride and other chain fragments in the condensed effluent water indicates the decomposition of PFSA ionomer and has long been noticed. Baldwin15 reported the detection of fluoride in the effluent of PEM electrolyzer and believed that it is the result of membrane mechanical failure. Extensive research has been conducted to elucidate the reaction pathways for membrane decomposition. Many controversial results and mechanisms have been reported in the literature, demonstrating the complex nature and the current inadequate understanding of the membrane degradation mechanisms. 

For the Nafion -based PEM fuel cells, the membrane conductivity decreased with increasing operating temperatures. The resistance points on the Re axis at the high-frequency end in Figure 6.49 can be treated approximately as the membrane through-plane resistance in PEM fuel cells other resistances, including the ionic resistance of the Nation ionomer and the cell contact resistance, may have made... 

H. L. Yeager and J. D. Mallnsky, "Permselectivity and Conductance of Perfluorinated Ionomer Membranes 1n Chlor-Alkali Electrolysis Process", presented at the Amer. Chem. Soc. Mtg., Philadelphia, Aug. 1984. 

Fig. U Electrochemical scheme of measuring the ionic conductivity of perfluorlnated Ionomer membranes.

M. Doyle, S.K. Choi and G. Proulx, High-temperature proton conducting membranes based on perfluorinated ionomer membrane-ionic liquid composites, J. Electrochem. Soc., 2000, 147, 34-37. 

Park HB, Shin HS, Lee YM, Rhim JW (2005) Atmealing effect of sulfonated polysulfone ionomer membranes on proton conductivity and methanol transport. J Membr Sd 247 103-110... 

Ionomer membranes fabricated from these polymers show high hydroxide ion conductivities, up to 144 mS cm at 80 °C. The membrane retained its high conductivity in hot water at 80 °C for 5000 h [118]. 

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