Influence of Melting Zone and Melt Homogeneity on Extrusion and Injection Molding Processes

Abstract

Abstract In this study, the melting behavior and melt homogeneity in a single screw extruder have been investigated to obtain better products in quality and higher productivity for extrusion and injection molding. For the analysis of the melting behavior, so-called “cooling experiments” were used. For the melt homogeneity evaluation, furthermore, molten polymer temperature fluctuations at the exit of a single extruder and injection molding machine were measured. As a result of these analyses, we have concluded that the melting process in extrusion and injection molding played an important role on improving product quality and its productivity. Based on experiments and analyses on the melting mechanism, we have developed a mixing and kneading screw configuration with a new melting process, in which the compulsory circulation flow in solid bed accelerates rapid melting of raw materials and melt homogeneity.