OBSERVATIONS ON DIELECTRIC ANISOTROPY OF SOLUTIONS OF FLEXIBLE POLYMERS IN FLOW

Measurements of the increase in the relative permittivity for solutions of polystyrenes, poly(p-ethoxystyrene), poly(methyl methacrylate), and poly(N-vinyl carbazole) when subjected to shear gradients are reported. The influences of such factors as shear rate, concentration, viscosity, solvent permittivity, polymer dipole moment, and polymer molecular weight on the phenomenon are described. An empirical correlation for the diverse data obtained with polystyrenes and poly(p-ethoxystyrene) has been established, but this relation does not entirely match the theoretically predicted effects. The various physical processes which may have an influence on the observed phenomenon are discussed.