Dielectric relaxation study of N -methyl formamide with glycols using time domain reflectometry technique

Abstract

The dielectric relaxation study that is static dielectric permittivity (∈₀) and relaxation time (τ) of amide of N-methyl formamide (NMF) with increasing volume percent propylene glycol (PLG) and BLG has been carried out at different temperatures. The time domain reflectometry (TDR) technique has been used to measure reflection coefficient in frequency range of 10 MHz to 20 GHz. The dielectric parameters have been obtained by fitting experimental data with the Havriliak–Negami equation. The experimental observation shows that the static dielectric permittivity and relaxation time decreases with increasing temperature. The experimental observation also shows that the static dielectric permittivity decreases and relaxation time increases with increasing percentage volume of Propylene glycol (PLG) and Butylene glycol (BLG) in NMF. The nature of (ϵ₀) and (τ) is same for the temperature ranges (20, 30, and 40°C). The thermodynamic parameters enthalpy (ΔH) and entropy (ΔS) of the binary mixture are also reported in this work.

Keywords:

• dielectric properties
• N-Methyl formamide
• propylene glycol
• butylene glycol
• TDR technique

Acknowledgements

Authors are thankful to Prof. S.C. Mehrotra, Department of Computer Science, Dr Babasaheb Ambedkar Marathwada University, Aurangabad for his guidance. The authors are also thankful to Dr V.P. Pawar, Department of Physics, Udaygiri College, Udgir, Latur for his help.