Sodium or quaternary ammonium modified Nafion membranes in forms of Nafion-Na+, Nafion-NMe+4:, Nafion-NEt+4 and Nafion-NBu+4: have bean prepared by neutralizing Nafion-H+ membrane with NaOH or tetraalkylammonium hydro...Sodium or quaternary ammonium modified Nafion membranes in forms of Nafion-Na+, Nafion-NMe+4:, Nafion-NEt+4 and Nafion-NBu+4: have bean prepared by neutralizing Nafion-H+ membrane with NaOH or tetraalkylammonium hydroxide aqueous solution. Intramolecular excimer formation and fluorescence polarisation methods using 1,3-di(1-pyrenyl)propane and acridine orange-as probes respectively have been employed for measurements of the microviscosity within those modified Nafion membranes. Results show that the probes are located in the fluorocarbon/water interface in the cluster of the membranes and the microviscosities around the probe molecules an in the range of ca. 120–1200 cp and increase in the order of Nafion-Na+ <Nafion-NMe+4<Nafion-NEt+4<Nafion-NBu+4. Furthermore, the microviscosity values of these membranes in dry form an higher than those in wet form.展开更多
基金Project supported by the National Natural Science Foundation of China
文摘Sodium or quaternary ammonium modified Nafion membranes in forms of Nafion-Na+, Nafion-NMe+4:, Nafion-NEt+4 and Nafion-NBu+4: have bean prepared by neutralizing Nafion-H+ membrane with NaOH or tetraalkylammonium hydroxide aqueous solution. Intramolecular excimer formation and fluorescence polarisation methods using 1,3-di(1-pyrenyl)propane and acridine orange-as probes respectively have been employed for measurements of the microviscosity within those modified Nafion membranes. Results show that the probes are located in the fluorocarbon/water interface in the cluster of the membranes and the microviscosities around the probe molecules an in the range of ca. 120–1200 cp and increase in the order of Nafion-Na+ <Nafion-NMe+4<Nafion-NEt+4<Nafion-NBu+4. Furthermore, the microviscosity values of these membranes in dry form an higher than those in wet form.