Steady-state and time-resolved fluorescence spectroscopic probing of microstructures and properties of perfluorinated polyelectrolyte membranes

• Published in: Journal of electroanalytical chemistry (1992) 1998-11, Vol.459 (1), p.15-28
• Main Authors: Bunker, Christopher E., Ma, Bin, Simmons, Kenya J., Rollins, Harry W., Liu, Jin-Tao, Ma, Jing-Ji, Martin, Charles W., DesMarteau, Darryl D., Sun, Ya-Ping
• Format: Article
• Language: English
• Subjects: Applied sciences; Exact sciences and technology; Exchange resins and membranes; Forms of application and semi-finished materials; Luminescent probes; Nafion; Polymer industry, paints, wood; Sulfonimide ionomer; Technology of polymers
• ISSN: 1572-6657; 1873-2569
• DOI: 10.1016/S0022-0728(98)00250-2

A systematic luminescence spectroscopic study of the microstructures and properties of Nafion®, the Dow Chemical films, and the newly synthesized sulfonimide ionomer membrane is reported. The strongly environment-sensitive luminescent probes 6-propionyl-2-( N, N-dimethylamino)naphthalene, 4-( N, N-dimethylamino)benzonitrile, pyrene, and ethidium bromide were used. The results suggest that the different perfluorinated ionomer membranes have generally similar properties with respect to the luminescent molecular probes and that the membrane structures consist of a substantial region that may be characterized as a heterogeneous mixture of water molecules and branches of the perfluorinated polymers. In addition, the effects of thermally stressing the ionomer membranes in an aqueous solution at temperatures up to 250°C on the properties of the membranes are evaluated and discussed.