865485-85-4Relevant articles and documents
Fluorinated aromatic polyether ionomers containing perfluorocyclobutyl as cross-link groups for fuel cell applications
Lee, Kwan-Soo,Jeong, Myung-Hwan,Kim, Young-Jea,Lee, Su-Bin,Lee, Jae-Suk
scheme or table, p. 1443 - 1453 (2012/07/28)
The cross-linkable copolymers (SHQx-TFVys) with varying degrees of sulfonation (DS) from 70 to 95% were prepared from potassium-2,5- dihydroxybenzenesulfonate (SHQ), decafluorobiphenyl (DFBP), and 4-(trifluorovinyloxy)-biphenyl-2,5-diol (TFVOH) as a cross-linkable moiety. To develop a highly stable polymer electrolyte membrane (PEM) for application in polymer electrolyte fuel cells (PEFC)s, cross-linked membranes were prepared by chemical cross-linking. The cross-linked membranes were synthesized by varying the amount of TFVOH (5-30 mol %) in order to achieve desirable PEM properties. The structures of the cross-linkable monomer and polymers were investigated by 1H and 19F NMR and FT-IR spectra. The cross-linked membranes exhibited good glass transition temperature and thermal stability up to 239-271 °C and 290-312 °C, respectively. The crosslinked membranes (DS range 80-95%) exhibited higher proton conductivity(0.098-0.151 S/cm) than Nafion 212 (0.092 S/cm). Moreover, all membranes possessed lower methanol permeability (13-132 × 10-8 cm2/s) compared with Nafion 212 (163 ×10-8 cm2/s) under the same measurement conditions. The H2/O2 single cell performance tests of the cross-linked membranes and Nafion 212 were performed. The CSHQ90-TFV10 exhibited the higher maximum power density (1.053 W/cm2) than that of Nafion 212 (0.844 W/cm2).
