Some 1‐substituted quaternary imidazolium compounds and related polymers: Qualitative and quantitative infrared analysis

It was found that 1‐substituted quaternary imidazolium compounds show some characteristic infrared (IR) activity. On quarternization of 1‐substituted imidazoles strong absorption bands appeared at about 1150 and 1550 cm−1 in the IR spectra of these compounds. The band at 1150 cm−1 was assigned to the position 2 C−H bending mode and the 1550 cm−1 band was attributed to a ring vibration mode of the quaternary imidazolium compounds. The concentration of the quaternary imidazolium units in a polymer can be determined by measuring the intensity of the absorption bands at 1150 or 1550 cm−1 in relation to another suitable absorption band of the spectrum.