Relaxation Time, Excess Relaxation Time and Dipole Moment of Binary Mixture of 2,3-Dichloroaniline and 2-Methoxyethanol using Frequency Domain Reflectometer

Abstract

Dielectric constant (e') and dielectric loss (e") of 2,3-Dichloroaniline (2,3-DCA), 2-Methoxyethanol (2-ME) and  binary mixtures of 2,3-DCA+2-ME in 1,4-dioxane solutions have been measured at microwave frequency 10.985 GHz at different temperatures 20 ⁰C, 30 ⁰C, 40 ⁰C and 50 ⁰C. Standing microwave techniques and Gopala Krishna’s single frequency concentration variation method have been used for above measurements. The measured values of e¢ and e¢¢ have been used to evaluate dipole moment (µ) and relaxation time (τ). The dielectric relaxation process of binary mixtures containing 70% mole fraction of 2,3-DCA have been calculated. It is found that the dielectric relaxation process can be treated as the rate process like the viscous flow process. Nonlinear variation of relaxation time with molar concentration of 2,3-DCA in the whole concentration range of the binary mixture indicates the existence of solute-solute and solute–solvent type of molecular association was predicted. Dipole moment (µ) of 2,3-DCA and 2-ME slightly non-linearly increases with rise in temperature. Excess inverse relaxation time (1/τ)^e calculated at different temperatures are found to be positive. All parameters (e'), (e"), (τ), (1/τ)^e and (μ) are calculated and discussed to yield information on the dipole alignment and molecular rotation of the binary liquid mixtures. From all the derived dielectric parameters, molecular interactions are interpreted through hydrogen bonding.

DOI: http://dx.doi.org/10.17807/orbital.v12i2.1368