High-frequency dielectric response of the binary mixture formamide–butylene glycol

Abstract

Dielectric relaxation study of formamide (FMD) has been carried out with butylene glycol (BLG) at different temperatures. Time domain reflectometry in reflection mode has been used to measure the reflection coefficient in the frequency range of 10 MHz–20 GHz. The dielectric parameters, that is, static dielectric permittivity (∈ 0) and relaxation time (τ) have been obtained by Fourier, transform and least square fit methods. The experimental results show non-linear variation in dielectric permittivity and relaxation time with volume fraction of BLG, confirm the structural formation due to the intermolecular interaction between FMD and glycol. The variation in excess permittivity (ϵ E), excess inverse relaxation times (1/τ)E, Kirkwood correlation factors (g eff, g f ), activation enthalpy (ΔH) and entropy (ΔS) for the binary mixtures have also been reported in this article.