N,N-dimethylformamide + 1,2-dimethoxyethane binary mixtures. The static dielectric constant from 40 to 80°C

The static dielectric constant (epsilon) has been measured at 2 MHz for N,N-dimethylformamide (1), 1,2-dimethoxyethane (2), and their nine binary mixtures covering the whole miscibility field (0 less-than-or-equal-to x1 less-than-or-equal-to 1) in the 40-80-degrees-C temperature range. The experimental epsilon values were fitted by empirical equations of the types epsilon = epsilon(T), epsilon = epsilon(x1), and epsilon = epsilon(T,x1). The mixing quantity deltaepsilon has been evaluated and fitted by a Redlich-Kister equation. The trend of deltaepsilon vs mole fraction curves shows negative deviations from ideality, and makes evident the presence of a stable dipolar interaction between unlike molecules.