Protonation of Sulfonated Poly(4,4′-diphenylether-1,3,4-oxadiazole) Membranes

✍ Scribed by Jerusa Roeder; Dominique Gomes; Mariela L. Ponce; Volker Abetz; Suzana P. Nunes

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 251 KB
• Volume: 208
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.200600515

✦ Synopsis

Abstract

This work describes the effect of sulfuric acid protonation on the properties of SPOD‐DPE membranes using FT‐IR and impedance spectroscopic analyses. The IR spectra showed the protonation of nitrogen atoms from oxadiazole rings, with a broad band complex in the region 3 000–2 100 cm^−1^ with two centered peaks at 2 590 and 2 440 cm^−1^. The SO characteristic absorption bands in SPOD‐DPE and sulfuric acid were specially studied in the region of 1 800–900 cm^−1^. The band shifts are associated to the interaction between acid groups and oxadiazole ring nitrogen atoms. The IR spectra evidenced the presence of three absorption species (HSO, SO and free H~2~SO~4~) depending on the sulfuric acid concentration. For the protonated SPOD‐DPE membranes, a proton conductivity around 10 mS · cm^−1^ was reached at 50 °C.

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