Dynamics of Chain Molecules in Dilute Solutions, with Special Reference to Non-Newtonian Viscosity

Abstract

SEVERAl aspects of the phenomena appearing when chain molecules in dilute solutions are subjected to a velocity field seem to be satisfactorily explained by the theory which I have recently proposed¹. In particular, the correct shape of the curve giving tan α (initial slope of extinction angle curve, as resulting from flow birefringence measurements) as a function of η₀ (viscosity of solvent) has been obtained; quantitative agreement has been observed between the calculated and the measured slope of the asymptote to the preceding curve, in the case of polystyrene; the correct dependence on molecular weight of the internal viscosity term B in tan α has been obtained (proportionality of B to the molecular weight, as established experimentally by Leray for polystyrene²); and finally it has become possible to understand some of the characteristics of non-Newtonian viscosity.