Dielectric studies on binary mixtures of formamide with ethanolamine using the time domain technique

Abstract

Dielectric relaxation measurements on formamide (FA) – ethanolamine (ETA) solvent mixtures have been carried out across the entire concentration range using time domain reflectometry technique at 15, 25, 35, and 45 0C over the frequency range from 10 MHz to 10 GHz. The mixtures exhibit a principle dispersion of the Davidson–Cole relaxation type at microwave frequencies. Bilinear calibration method is used to obtain complex permittivity ε*(ω) from complex reflection coefficient ρ*(ω) over the frequency range 10 MHz to 10 GHz. The excess permittivity εE, excess inverse relaxation time (1/τ)E, Kirkwood correlation factor geff , and thermodynamic parameters such as Gibbs energy of activation ΔG and molar enthalpy of activation ΔH are also calculated to study the solute–solvent interaction. Keywords: activation energy, excess parameters, Kirkwood correlation factor, time domain reflectometry