Influence of polyvinylpyrrolidone on the interaction between water and methanol

The present work aims to determine the influence of a dissolved polymer, polyvinylpyrrolidone, on the interaction between water and methanol. First, the dynamic viscosities were measured for polymer solutions by a rotational concentric cylinder at 25 ºC and for the polymer concentration range from 0.1 to 0.6 g/dl. The results show a polynomial dependence of the viscosity on polymer concentration. On the hypothesis of a quasi-binary system, a pseudo Grumberg-Nissan constant, d'p, was introduced to quantify the interaction between unlike molecules in the presence of polymer. The interaction bet...