Cation‐exchange membranes: Comparison of homopolymer, block copolymer, and heterogeneous membranes

Journal of Applied Polymer Science (Impact Factor: 1.4). 12/2011; 124(S1):E66 - E72. DOI: 10.1002/app.35524

ABSTRACT Three types of sulfonic cation-exchange membranes were compared: (a) homogenous membranes prepared by sulfonation of poly(2,6-dimethyl-1,4-phenylene oxide) or poly[oxy(1,4-phenylene)oxy(1,4-phenylene)carbonyl(1,4-phenylene)] and solution casting of the sulfonated products, (b) membranes prepared by sulfonation of poly [styrene-block-(ethene-stat-butene)-block-styrene] film, and (c) heterogeneous membranes prepared by melt-blending linear polyethylene and particles 10–25 μm particles of sulfonated cation-exchanger followed by compression molding. At the same ion-exchange capacity (IEC), the membranes based on the block copolymer showed considerably higher ionic conductivity than the homogeneous membranes. Though having a higher IEC, the heterogeneous membranes were less conductive than the other investigated membranes. Their advantage consists in the ease of preparation and superior resistance to oxidative environment. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

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