Volumetric and Ultrasonic Studies of Molecular Interactions of PEG 400 and PEG 4000 in Aqueous Niacin Solutions at Different Temperatures

At multiple temperatures, 288.15–318.15 K, the density and speed of sound values for PEGs of molecular weights 400 and 4000 in aqueous niacin solutions were measured at concentrations of 0.07, 0.08, and 0.09 mol·kg–1. Utilizing these experimental data, the apparent molar properties and partial molar properties were determined to analyze the interactions in aqueous niacin solutions with poly(ethylene glycol)s (400/4000). The volumetric...