H-bonded molecular interaction study on binary mixtures of mono alkyl ethers of ethylene glycol with different polar solvents by concentration dependent dielectric analysis

Abstract

Static dielectric constant measurements on binary mixtures of the homologous series of mono alkyl ethers of ethylene glycol with six different characteristic polar solvents i.e. ethyl alcohol, ethylene glycol, glycerol, water, dimethyl formamide and dimethyl sulphoxide over the entire concentration range were carried out using precision LCR meter and a four terminal liquid dielectric test fixture at 1 MHz and 25°C. The concentration dependent excess dielectric constant and Kirkwood correlation factor were determined for the confirmation of solvent–cosolvent heterogeneous molecular interactions. The values of stoichiometric ratio corresponding to maximum interactions between the mixtures constituents were also estimated from the concentration dependent values of εE. It is observed that the behaviour of heterogeneous interactions significantly varies with the increase in molecular size of the homologous series and also with the change in the mixture constituents. Comparative dielectric parameters values of the studied binary mixtures were applied to recognize the dipolar orientation due to heterogeneous interactions of mono alkyl ethers with hydroxyl group(s) containing solvents and non-hydroxyl group containing solvents.