Viscosity and density data for the system of hexanedioic acid dissolved in poly(ethylene glycol) 6000 (PEG6000) + water solvents at 298.15, 303.15, 308.15 and 313.15 K have been determined. The viscosity B-coefficients and partial molar volumes for hexanedioic acid in PEG aqueous solutions have been calculated. The effect of temperature and PEGs concentration on the B-coefficients are discussed on the basis of the Feakins equation. The contribution of solute and mixed solvents to the activation parameters, (Deltamu(3)(not equal), DeltaH(3)(not equal), DeltaS(3)(not equal), DeltaG(12)(0not equal), DeltaH(12)(0not equal) and DeltaS(12)(0not equal)), for viscous flow of the solution have been evaluated, together with the Gibb's energy of transfer for the solute from the ground state solvent to the hypothetical viscous transition state solvent (DeltaG(3)(not equal)(1 - 1')). (C) 2003 Elsevier Science B.V All rights reserved.