Thermodynamics of Amide + Amine Mixtures. 1. Volumetric, Speed of Sound, and Refractive Index Data for N,N-Dimethylformamide + N-Propylpropan-1-amine, + N-Butylbutan-1-amine, + Butan-1-amine, or + Hexan-1-amine Systems at Several Temperatures

Values of density (ρ), speed of sound (c) and refractive index (nD) for N,N-dimethylformamide (DMF) + N-propylpropan-1-amine (DPA) or + butan-1-amine (BA) mixtures at (293.15−303.15) K, and for DMF + N-butylbutan-1-amine (DBA) or hexan-1-amine (HxA) mixtures at 298.15 K are reported. Density and speed of sound measurements were conducted using a vibrating-tube densimeter and sound analyser, Anton Paar model DSA5000; refractive index values, nD values were obtained by means of a RFM970 refractometer from Bellingham+Stanley. The experimental ρ, c and nD values have been used to determine excess molar volumes, VmE, excess adiabatic compressibilities, κSE, excess speeds of sound, cE, excess thermal expansion coefficients, αpE, and excess refractive indices, nDE. This set of data shows the existence of interactions between unlike molecules and of structural effects in the mixtures under study. VmE values of solutions including linear secondary amines are lower than those of mixtures with linear primary amines....