Acid-base properties of poly(1-vinylazoles) in aqueous solution

The interaction of poly(1-vinylimidazole) and poly(1-vinyl-1,2,4-triazole) with HCl and alkalies in aqueous and water-salt solutions was investigated by potentiometric titration, viscosimetry, ¹H and ¹³C NMR, and UV spectroscopy. The effect of the nature and concentration of low-molecular counterions was found. The interaction of poly(1-vinylazoles) with the acid results in the protonation of the azole cycle. The interaction of poly(1-vinylazoles) with alkalies is stipulated by the capability of the pyridine N atom of forming a coordination bond with the metal ion and that of the unsaturated pi-system of the heterocycle of coordinating with the anions.