Density, viscosity, surface tension and spectroscopic studies for the liquid mixture of tetraethylene glycol + N,N-dimethylformamide at six temperatures

Abstract

Density (ρ), viscosity (η) and surface tension (γ) are always significant physicochemical properties for liquid mixtures. In this work, the ρ, η and γ data for the liquid mixture of tetraethylene glycol (T4EG) + N,N-dimethylformamide (DMF) were systemically measured from 293.15 to 318.15 K with a step of 5 K and p = 0.1 MPa. From these physicochemical properties, viscosity deviation (∆η), excess molar volume (VmE), and surface tension deviation (∆γ) were calculated. Meanwhile, VmE, ∆η and ∆γ of activation functions were fitted with Redlich-Kister (R-K) equation to evaluate the coefficients and standard deviations. The η values of the liquid mixtures were fitted with Grunberg and Nissan equation and three-body McAllister expression. UV–vis and FTIR spectra were measured to discuss the intermolecular interaction of T4EG with DMF, which indicated that there was hydrogen bonds interaction between hydroxyl hydrogen atoms in T4EG and oxygen atoms in DMF.