Studies in Newtonian Flow. IV. Viscosity vs Molecular Weight in Liquids; Viscosity vs Concentration in Polymer Solutions

This is the final installment in the current series entitled ``Studies in Newtonian Flow.'' In this paper, the molecular weight—free-space function applicable to n-paraffins m=100 through m=240 at various temperatures is further generalized to apply to homologous series of all Newtonian liquids at constant temperature. The resulting molecular weight function thereby loses some fidelity, and the slopes and intercepts no longer have physical significance. The generalized logarithmic decrement equation nevertheless reproduces viscosity data over extended ranges of molecular weight (at constant temperature) far better than expressions previously proposed. The equation is extended to apply to mixtures of liquids and finally to polymer solutions.