Densities and Viscosities of Polyhydroxy Solutes in Aqueous Tetraethylammonium Bromide Solutions at Different Temperatures

Infinite-dilution standard partial molar volumes, V-2 degrees, and the Jones Dole viscosity B-coefficients of some saccharides and their polyols, (-)-D-arabinose, (+)-D-arabitol, (+)-D-xylose, xylitol, (-)-L-sorbose, D-sorbitol, (+)-D-galactose, galactitol, (+)-D-glucose, and (+)-D-maltose monohydrate, have been obtained in aqueous (0.05, 0.5, 1.0, and 2.0) mol.kg(-1) tetraethylammonium bromide (Et4NBr) solutions from apparent molar volumes, V-2,V-phi, and relative viscosities, eta(r), data, respectively, at (288.15, 298.15, 308.15, and 318.15) K under atmospheric pressure, p = 0.1 MPa. The corresponding transfer parameters (Delta V-t(2)degrees, and Delta B-t) along with isobaric expansion coefficients, (partial derivative V-2 degrees/partial derivative T)B, their second-order derivatives (partial derivative V-2(2)degrees/partial derivative T-2, pair (V-AB, eta(AB)), and triplet (V-ABB, eta(ABB) ) volumetric, and rheological interaction coefficients have been determined, because these parameters are sensitive to structural changes occurring in solutions due to temperature and concentration changes. Pentoses, hexoses, and their polyols exhibit negative transfer volumes in presence of tetraethylammonium bromide, which indicates the dominance of hydrophobic-ionic interactions. The interaction coefficient values are higher for polyols having nonplanar sickle conformations. Also the results have been compared with those in presence of ammonium bromide. The results confirm that the solute-solvent/cosolute interactions are dependent on the stereochemistry and molecular conformations of the polyhydroxy solute and cosolute.