Structure and Properties of PBIs

11 Infrared spectra of PBI-JCH3PO4 membranes. (Reprinted with permission ftom Elsevier (1999). Copyright 1999 Elsevier [29].) 

By using the dissociation constant of protonated 2-phenyl benzimidazole = 5.9x 10 mol/l) and the first dissociation constant of phosphoric acid K = 6.9 H3PO4 X 10 mol/1), they obtained the equilibrium constant AT = 1.17 x 10.  

ANHYDROUS PROTON-CONDUCTING POLYMERS FOR HIGH-TEMPERATURE PEMFCs 

The membrane proeessing and morphology have also significant effects on the proton transport and eonduetivity. The NMR study by Jayakody et al. [140] showed that the proton diffusivity is about an order of magnitude higher in the PPA-cast membranes than in DMAe-east membranes. Apparently an additional proton transport mechanism exists involving rapid exchange between the phosphoric acid and 

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