Nafion, Flemion performance

FIG U RE 2.2 Chemical structures of perfluorinated ionomers with sulfonic acid (la = Nafion, Flemion lb = Aciplex 2a = Dow, Hyflon Ion 2b = 3M 2c = Asahi Kasei 3 = Asahi Glass) and bis[(perfluoro)alkyl sulfonyl] groups (4). (Reprinted with permission from Peckham, T. J., Yang, Y, and Holdcroft, S. et al., Proton Exchange Membrane Fuel Cells Materials, Properties and Performance, Wilkinson, D. P. et al., Eds., Figure 3.16, 138, 2010, CRC Press, Boca Raton. Copyright (2010) CRC Press.)... 

In Xuezhong Du etal. (2001), Japanese Aciplex and Flemion and Chinese Shanghai alternatives to Nafion are compared with Nafion in terms of their performance, and none is overwhelming. The latter alternatives have not yet caught on in the international scene. Price comparison is not made available. 

The electrolysis of potassium chloride [744740-7], KC1, to produce chlorine and potassium hydroxide in membrane cells requires similar but unique membranes. Commercial membranes currently employed in high performance membrane electrolyzers include Du Pont s Nafion 900 series and Asahi Glass s Flemion 700 series. 

The forth direction, analytical modeling for understanding the behaviors of these materials, has been popular approach. Testing and characterization have been conducted for developing the models. Such attempts have been done especially for ionic polymer metal composites (IPMCs)[58, 70, 72, 120]. Nemab Nasser and his co-workers carried out extensive experimental studies on both Nafion- and Flemion-based IPMCs consisting of a thin perfluorinated ionomer in various cation forms, seeking to imderstand the fundamental properties of these composites, to explore the mechanism of their actuation, and finally, to optimize their performance for various potential applications[121]. They also performed a systematic experimental evaluation of the mechanical response of both metal-plated and bare Nafion and Flemion in various cation forms and various water saturation levels. They attempted to identify potential micromechanisms responsible for the observed electromechanical behavior of these materials, model them, and compare the model results with experimental data[122]. A computational micromechanics model has been developed to model the initial fast electromechanical response in these ionomeric materials[123]. A number... 

FIGURE 12.13 The comparison of single-cell performance between Nafion 1135 membrane and Flemion SH80 membrane. (From Yi Baolian, Fuel Cell—Principal, Technology, ApplicationfM], The Chemical Industrial Press, Beijing, China, 2003.)... 

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