Comparison of PEM Properties of Copoly(aryl ether ether nitrile)s Containing Sulfonic Acid Bonded to Naphthalene in Structurally Different Ways
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- 作者：Yan Gao ; Gilles P. Robertson ; Dae-Sik Kim ; Michael D. Guiver ; Serguei D. Mikhailenko ; Xiang Li ; Serge Kaliaguine
- 刊名：Macromolecules
- 出版年：2007
- 出版时间：March 6, 2007
- 年：2007
- 卷：40
- 期：5
- 页码：1512 - 1520
- 全文大小：192K
- 年卷期：v.40,no.5(March 6, 2007)
- ISSN：1520-5835
文摘
The study represents a comparative investigation of three series of high molecular weight aromaticpoly(aryl ether ether nitrile) copolymers (SPAEEN-n), containing different sulfonated naphthalene groups, wheren (in the range 0-80 mol %) refers to molar percentage of repeat units containing the sulfonic acid function. Thethree series of SPAEEN-n copolymers were synthesized via potassium carbonate-mediated nucleophilicpolycondensation reactions of commercially available monomers: 2,6-difluorobenzonitrile (2,6-BFBN), one ofthree dihydroxynaphthalenesulfonate (DHNS) monomers, and unsulfonated 4,4'-biphenol (BP), incorporated forthe purpose of adjusting the sulfonic acid content. The incorporation of the sulfonated repeat unit into copolymersand their structures were confirmed by 1H NMR and FT-IR spectroscopy. Products were solvent-cast intomembranes of varying ionic content as proton exchange membrane (PEM) materials for fuel cells applications.Ion exchange capacity (IEC), thermal stabilities, swelling, and proton conducting properties of the membraneswere investigated in relation to their structures and compared with those of perfluorinated ionomer (Nafion 117).Films of SPAEENH copolymers in acid form all showed high thermal stabilities with glass transition temperatures(Tg) > 224 
C and decomposition temperatures (Td) > 264 C. In general, the SPAEENH copolymers exhibitedlow moisture absorption and in some instances high proton conductivities (from 10-2 to 10-1 S/cm) comparableto that of Nafion 117 at similar water uptake, swelling, and H2O/SO3H ratio.
C and decomposition temperatures (Td) > 264 C. In general, the SPAEENH copolymers exhibitedlow moisture absorption and in some instances high proton conductivities (from 10-2 to 10-1 S/cm) comparableto that of Nafion 117 at similar water uptake, swelling, and H2O/SO3H ratio.