Flow patterns in calcium carbonate and titanium dioxide filled polyethylene in the entrance region of a capillary die

Abstract Experiments to determine the influence of calcium carbonate and titanium dioxide on flow patterns in die entrance regions are reported. The addition of loadings of calcium carbonate and tatanium dioxide of 5 volume percent and more is found to suppress the development of vortices in low density polyethylene at the entrance of a 180° entrance angle die. Vortex suppression was found in more complex entrance regions as well. Similar behavior has been found for carbon black compounds.