The densities and viscosities of unsaturated solutions of sodium perchlorate + poly(ethylene glycol) + water were experimentally measured at temperatures of 288.15, 298.15 and 308.15 K. The solution concentrations of poly(ethylene glycol) with an average molecular weight of 4000 ranged from 0.25 to 33.91 (mass%) and from 10.12 to 37 (mass%) of NaClO4. The electrolyte and polymer non-random two liquid models were extended for representing of the excess molar volume and the dynamic viscosity of the above system. At these specific temperatures, the model correlations compared favorably with the experimental data for both the density and the viscosity. (c) 2012 Elsevier B.V. All rights reserved.