Dielectric behaviour of the 2-methoxyethanol–1,2-dimethoxyethane solvent system

Abstract

The static relative permittivity at various temperatures ranging from –10 to +80 °C has been measured for 2-methoxyethanol, 1,2-dimethoxyethane and nine mixtures covering the whole miscibility field expressed by the mole fraction of 2-methoxyethanol (0 ⩽X₁⩽ 1).

Equations describing the dependence of the relative permittivity on temperature [ε=ε(T)], and binary composition [ε=ε(X₁)], have been checked. Furthermore, a single function ε=ε(T, X₁) has been obtained by combining the previously cited monovariant equations. As a rule, the calculated values agree very well with the experimental ones.

The excess extrathermodynamic parameter ε^E, which provides much useful information about the possibility of forming solvent–cosolvent complexes is briefly discussed. This fact has been interpreted on the basis of specific interactions of any kind between different molecules, taking into account geometric effects and steric hindrances.