A New Mathematical Model for the Characterization of Viscosity Variations in the Aqueous Solutions of Monoalcohols and Polyalcohols

Abstract

This study aims to investigate the viscosity of binary mixtures of water with different monoalcohols and polyalcohols. The viscosity values of the mixtures of methanol, ethanol, 1-propanol, and 2-propanol were taken from a study published by Herraez and Belda (2004). The values for ethylene glycol, glycerin, and sorbitol were measured using a similar protocol. The viscosity of the mixture is expressed as a function of the molar fraction of the alcohols that ranges from 0 (pure solvent, water in this case) to 1 (pure solute). To represent the viscosity of these mixtures, a new variable, Φ, was introduced. This representation provides a function, η = f(Φ), that has an exponential nature, with which excellent correlation coefficients are achieved with only one coefficient for monoalcohols or two coefficients for polyalcohols. Additionally, the variable Φ highlights the possible critical points, where physicochemical interactions occur between the components of the mixture.