1H solid-state NMR investigation of structure and dynamics of anhydrous proton conducting triazole-functionalized siloxane polymers.

(1)H MAS solid-state NMR methods are applied to elucidate the conduction mechanism of an anhydrous proton conducting triazole-functionalized polysiloxane. At temperatures below T = 260 K, hydrogen bonding between neighboring heterocycles is observed and a dimer formation can be excluded. From the temperature dependence of (1)H MAS NMR spectra, different dynamic processes of the triazole ring contributing to the proton conduction process are qualitatively and quantitatively analyzed and detailed insight into the conduction mechanism and temperature-dependent structural changes is obtained. Although the dynamics processes on the molecular level are qualitatively in good agreement with the findings from macroscopic conductivity measurements, temperature-dependent factors on mesoscopic scales beyond the local molecular mobility influence the macroscopic conductivity and hamper quantitative interpretation.