Thermodynamic study of poly(ethylene glycol) in water/acetone solutions by viscometry

Abstract

Abstract In this work, the intrinsic viscosities of poly(ethylene glycol) (PEG) with a molar mass of 20,000 g·mol-1 were measured in water/acetone solutions from (283.1 to 313.1) K. The expansion factors of the polymer chains were calculated from the intrinsic viscosity data. The thermodynamic para­meters (entropy of dilution parameter, the heat of dilution para­meter, θ temperature, polymer-solvent interaction parameter and second osmotic virial coefficient) were derived by the temperature dependence of the polymer chain expansion factor. The thermodynamic parameters indicate that mixtures of water/acetone are changed to the poorer solvents for PEG, by increasing temperature and volume fractions of acetone. Also, the temperature dependency of segment-segment and segment-solvent interactions for PEG in mixed water/acetone, is decreased by increasing volume fractions of acetone.