Polarity studies in two classes of imidazolium-based protic ionic liquids (PILs) possessing [HSO4]−,[HCOO]−,[CH3COO]− and [CH3CH2COO]− anions were carried out using a solvatochromic method from 298.15 to 353.15 K. For 1-methylimidazolium class of PILs, ET (30) was found to be independent over the entire range of temperature, while ET (30) was noted to decrease with a rise in temperature in the case of 1-butylimidazolium class of ...
