1984 Volume 41 Issue 7 Pages 413-420
Flow characteristics of a polymeric system filled with a large quantity of inorganic powdered materials were studied by means of a cone-plate rheometer and a capillary extrusion rheometer. The viscosity of the filled-dispersed polymer is governed by the volumetric loading of filler φ under Brinkman's equation in the range of lower γ. The ratio of entrance pressure loss to apparent shear stress (Pc/τw′), which signifies an elastic property, increases with increasing γ, whereas the φ dependence of calcium carbonate is oppisite to that of mica. The die swell also depends upon φ and τw′, while in the case of calcium carbonate the effect varies markedly with the size of the particles. The surface treatment of the filler affects the flow in a capillary, enlarging η as φ becomes larger.
