Viscosity of the binary mixtures of polymers/solvent: (polystyrene/toluene), (polymethylmethacrylate/acetone), (polystyrene/benzene), (polystyrene/cyclohexane), and (polymethylmethacrylate/chloroform) were measured at different temperatures by a Haake viscometer. The samples of polymer/solvents mixtures used in the viscometry measurements were in low concentration of polymer (maximum concentration 0.25 g/cm(3)). The measured viscosities were used to evaluate the parameters of the modified Eyring's viscosity equation. (C) 2003 Wiley Periodicals, Inc.