Pseudospinodal curves and scaling of the shear viscosity of binary mixtures in the critical region

The shear viscosity of binary liquid mixtures shows a weak anomaly in the critical region. Its empirical formula η=ηidεₛₚ^-φ is used first to determine Tₛₚ and found to provide reasonable representations of the experimental results. The relevance of this equation to some current theoretical predictions and the general validity are discussed. In addition, it is shown that the shear viscosity satisfies scaling law relations similar to those previously established for equilibrium properties.