Dielectric characterization and molecular interaction behaviour in binary mixtures of methyl acetate with 1-butanol and 1-pentanol

Abstract

The dielectric constant (ɛ_s) and relaxation time () of binary mixtures of methyl acetate with alcohols (1-butanol and 1-pentanol) have been investigated at fifteen molar concentrations over the entire mixing range at 288 K, 298 K, 308 K and 318 K using time domain reflectometery technique over the frequency range from 10 MHz to 10 GHz. The relaxation in these mixtures can be described by a single relaxation time using the Debye model. The concentration dependent plots of excess dielectric constant (ɛ^E), excess inverse relaxation time (1/)^E, Kirkwood correlation factor (g^eff), thermodynamic parameters such as enthalpy of activation (H) and Gibbs free energy (G) of activation and Bruggman factor (f_B) have been used to explore the complexes formed between unlike molecules, dipolar ordering, hydrogen bond molecular connectivity’s and their strength in the binary mixtures. Results confirm that there are strong hydrogen-bond interactions between unlike molecules of ester-alcohol mixtures.