The Relative Permittivity of N,N-Dimethylformamide/1,2-Dimethoxyethane Binary Mixtures from -10 to 40 C

Binary solutions of N,N-dimethylformamide and 1,2-dimethoxyethane have been investigated by means of dielectric measurements at temperatures ranging from −10 to +40°C, and for nine mixtures covering the whole miscibility field expressed by the mole fraction of one component (0≤X1≤1). The experimental data were used to study the dependence of ɛ on T and X1, of the type ɛ = ɛ(T), ɛ = ɛ(X1), and ɛ = ɛ(T,X1). Further, the excess mixing function ɛE has been evaluated in order to identify particular patterns of interaction between unlike molecules and any other factor that could modify such patterns. The minimum in the ɛE vs. composition plots suggests the formation of an adduct of stoichiometric ratio DMF∶DME=1∶1 at all the investigated temperatures.