Acoustic, viscometric and spectroscopic study of molecular interactions in butyl acrylate + 1-butanol, + 2-butanol, + 2-methyl-1-propanol, + 2-methyl-2-propanol systems at different temperatures: Experimental and theoretical approach

The speeds of sound, u and viscosities, η of butyl acrylate +1-butanol/2-butanol/2-methyl-1-propanol/2-methyl-2-propanol binary mixtures across the entire composition range were measured at ambient temperatures and pressure, p = 100 kPa. Using the measured data, viz., excess isentropic compressibilities, excess intermolecular free lengths, excess speeds of sound, excess molar isentropic compressibilities, excess specific acoustic impedances and deviations in viscosity were evaluated. The partial molar isentropic compressibilities and excess partial molar isentropic compressibilities of the components over whole composition range; and at infinite dilution are calculated. The variation of these parameters has been interpreted in relations to intermolecular interactions in these mixtures. The results indicate that the extent of butyl acrylate-alkanol interactions follow the order: 1-butanol >2-butanol >2-methyl-1-propanol >2-methyl-2-propanol. The speeds of sound were theoretically calculated by means of various theories/relations and the viscosities of these mixtures were correlated by means of several empirical and semi-empirical equations and the outcomes are compared with experimental data. The relative applicability of these theories/relations has been discussed. Further to confirm the nature and extent of prevailing intermolecular interactions, the FT-IR spectra of pure butyl acrylate, isomeric butanols and their near equimolar mixtures were recorded and analyzed to validate the prevailing interactions.