Comparison of homogenization of polymers during the extrusion in screw extruder or screw-disk extruder

The process of homogenization of low-density polyethylene/coloring marker system in either single-screw extruder or screw-disk extruder has been compared (Fig. 1 and 2). The effects of marker concentration (0.022-0.087 %)(Figs. 4, 5, 8) and tangential velocity (0.067-0.134 m/s) (Fig. 6) on the degree of the system homogenization both in the longitudinal section and cross-section (Fig. 9) were investigated. Homogenization degree (Fig. 7) was investigated organoleptically (visually). In single-screw extruder the marker is distributed in homogenization zone from the middle of extrudate to the exterior surface while in screw-disk extruder - in interdisk slit from exterior surface of an extrudate to its middle. It was found that in latter case the homogenization of the system was much better than in first one.