| Abstract: | Recently, a new method of generalization of the zero shear viscosity of liquids has been proposed. The method utilizes a modified Doolittle formula and the temperature-dependent volume, as expressed by the corresponding states theory of liquids. Furthermore, the glass-transition temperature has been employed as the scaling parameter. The proposed treatment allowed prediction of the correlation between: (i) viscosity, η, and temperature, T, (ii) η and the molecular weight of polymer, (iii) η and concentration, and (iv) the combined effect of these variables. At present, the method is extended to the pressure, P, effect. Furthermore, by substituting the free volume fraction in the Doolittle formula by the theoretical “hole fraction,” a master-relation is proposed that provides means for predicting η = h(T, P) dependence. |
