A new model for zero-shear viscosity, eta, is proposed. The model combines the Simha-Somcynsky (SS) statistical thermodynamic theory of liquids with the Eyring Significant Structure (ESS) transport theory. Using the new model, a successful linearization of the experimental viscosity vs, hole fraction data was obtained. A comparison between the new model and Utracki's relation, 1n eta = a(0) + a(1)/(h + a(2)) was also made. The former was found to be more successful for both linear and nonlinear structures, provided that an appropriate choice of the degrees of freedom of normal and activated states was made. The proportionality constant of the activation energy and transmission coefficient were also calculated for each species. (C) 1999 John Wiley & Sons, Inc.