Densities, ultrasonic speeds, viscosities and excess properties of binary mixtures of methyl methacrylate with N,N-dimethylformamide and N,N-dimethylacetamide at different temperatures

Abstract

The densities, ρ, ultrasonic speeds, u and viscosities, η of binary mixtures of methyl methacrylate (MMA) with N,N-dimethylformamide (DMF) and N,N-dimethylacetamide (DMA), including those of pure liquids, over the entire composition range were measured at temperatures (288.15, 293.15, 298.15, 303.15, 308.15, 313.15, and 318.15) K and atmospheric pressure. From the experimental results, the excess molar volume, $V_{\text{m}}^{\text{E}}$, and excess isentropic compressibility, ${\kappa }_{\text{s}}^{\text{E}}$, excess isobaric coefficient of thermal expansion, ${\alpha }_{\text{p}}^{\text{E}}$ and excess molar isobaric expansion, $E_{p\text{,}m}^{\text{E}}$ were calculated. The excess partial molar volume, ${\overline{V}}_{m\text{,}1}^{\text{E}}$ and ${\overline{V}}_{m\text{,}2}^{\text{E}}$ and excess partial molar isentropic compressibility, ${\overline{K}}_{s\text{,}m\text{,}1}^{\text{E}}$ and ${\overline{K}}_{s\text{,}m\text{,}2}^{\text{E}}$ over the whole composition range; and partial molar volume, ${\overline{V}}_{m\text{,}1}°$ and ${\overline{V}}_{m\text{,}2}°$, partial molar isentropic compressibility, ${\overline{K}}_{s\text{,}m\text{,}1}°$ and ${\overline{K}}_{s\text{,}m\text{,}2}°$, excess partial molar volume, ${\overline{V}}_{m\text{,}1}^{°\text{E}}$ and ${\overline{V}}_{m\text{,}2}^{°\text{E}}$, excess partial molar isentropic compressibility, ${\overline{K}}_{s\text{,}m\text{,}1}^{°\text{E}}$ and ${\overline{K}}_{s\text{,}m\text{,}2}^{°\text{E}}$ at infinite dilution, and excess partial molar isobaric expansion, ${\overline{E}}_{p\text{,}m\text{,}1}^{\text{E}}$ and ${\overline{E}}_{p\text{,}m\text{,}2}^{\text{E}}$ over the whole composition range have also been calculated. The variations of these parameters with composition and temperature of the mixtures are discussed in terms of molecular interaction in these mixtures. It is observed that the MMA-DMF/DMA interactions in these mixtures follow the order: DMF < DMA. Further, the viscosities of these binary mixtures were correlated theoretically by using various empirical and semi-empirical models and the results were compared with the experimental findings.

Introduction

Mixed solvents are frequently used as media for many chemical, industrial and biological processes, because they provide a wide range of desired properties and the knowledge of the volumetric, acoustic and transport properties of non-aqueous binary liquid mixtures has significance in theoretical and applied areas of research [1], [2], [3]. The ultrasonic speed may be considered as a thermodynamic property, provided that a negligible amount of ultrasonic absorption of the acoustic waves of low frequency and of low amplitude is observed; in which case, the ultrasonic absorption of the acoustic waves is negligible [4]. In continuation to our on-going research [5], [6], [7] on binary and ternary mixtures containing acrylate monomers, here we report the results of our study on the binary mixtures of methyl methacrylate (MMA) with N,N-dimethylformamide (DMF) and N,N-dimethylacetamide (DMA).

The MMA, DMF and DMA are polar, aprotic and non-associated solvents. Amides are convenient model compounds for investigating peptide and protein-solvent interactions [8], whereas, acrylate monomers are often required for their industrial applications such as making cleaning products, antioxidant agents, amphoteric surfactants, paints, inks, adhesives, dispersions for textiles, paper, etc., and are also interesting theoretically as they have unsaturated structure beside a carbonyl group in the molecule [9]. Despite many industrial and theoretical interests, the mixtures containing amides and acrylate monomers are not investigated from their physicochemical behaviour. Literature survey indicates that there have been a number of studies [10], [11], [12], [13] on the mixtures of acrylate monomers with alkanols, alkanes, aromatic hydrocarbons, 1,4-dioxane, etc. To the best of our knowledge, no studies on the binary mixtures of MMA with DMF/DMA have been reported in the literature.

In the present paper, we report values of density, ρ, ultrasonic speed, u and viscosity, η of the binary mixtures of MMA with DMF and DMA, including those of pure liquids at temperatures (288.15, 293.15, 298.15, 303.15, 308.15, 313.15, and 318.15) K and atmospheric pressure, covering the entire composition range expressed by the mole fraction x₁ of MMA. The experimental values of ρ, u and η have been used to calculate the excess molar volume, $V_{\text{m}}^{\text{E}}$, and excess isentropic compressibility, ${\kappa }_{\text{s}}^{\text{E}}$, excess isobaric coefficient of thermal expansion, ${\alpha }_{\text{p}}^{\text{E}}$ and excess molar isobaric expansion, $E_{p\text{,}m}^{\text{E}}$ were calculated. The excess partial molar volume, ${\overline{V}}_{m\text{,}1}^{\text{E}}$ and ${\overline{V}}_{m\text{,}2}^{\text{E}}$, excess partial molar isentropic compressibility, ${\overline{K}}_{s\text{,}m\text{,}1}^{\text{E}}$ and ${\overline{K}}_{s\text{,}m\text{,}2}^{\text{E}}$ over the whole composition range; partial molar volume, ${\overline{V}}_{m\text{,}1}°$ and ${\overline{V}}_{m\text{,}2}°$, partial molar isentropic compressibility, ${\overline{K}}_{s\text{,}m\text{,}1}°$ and ${\overline{K}}_{s\text{,}m\text{,}2}°$, excess partial molar volume, ${\overline{V}}_{m\text{,}1}^{°\text{E}}$ and ${\overline{V}}_{m\text{,}2}^{°\text{E}}$ and excess partial molar isentropic compressibility, ${\overline{K}}_{s\text{,}m\text{,}1}^{°\text{E}}$ and ${\overline{K}}_{s\text{,}m\text{,}2}^{°\text{E}}$ of the components at infinite dilution, and excess partial molar isobaric expansion, ${\overline{E}}_{p\text{,}m\text{,}1}^{\text{E}}$ and ${\overline{E}}_{p\text{,}m\text{,}2}^{\text{E}}$ over the whole composition range have also been calculated. The variations of these parameters with composition and temperature of the mixtures are discussed in terms of molecular interaction in these mixtures.