The research of the extrusion equipment design's influence on the quality of components’ mixing in the construction-polymeric composition

The paper presents the results of the research on developing a new design of the middle layer extruder's auger in the structure of the coextrusion equipment, in which the polymeric and construction waste's recycling goes on. An improvement of the extruder due to the new auger's design in the mixing section is the new engineering solution, presented here. The researches have shown that the quality of the coextrusion composition, obtained from the polymeric materials’ waste, depends on the design of the extrusion equipment as well as on the methods used for controlling this equipment. The extruder's design, in its turn, is determined by the geometrical characteristics of the employed augers and by the recycled material properties. It is found out that with the increase in the length of the mixing section LCM the value of the extruder's interturn space volume increases, depending on the mixing section's lengthVa(LCM); this results in the decrease in the heterogeneity coefficientKH. It is demonstrated that the design of the multisectional worm auger is applicable for processing compound compositions from the filled waste of products from polyethylene, polypropylene, and polyvinylchloride in the coextrusion equipment. The experiments with the designed multisectional auger showed a considerable increase in the quality of the extrudate from construction-polymeric composition due to the increase of the homogeneity of mixing components, being different in characteristics and rheology. It is ascertained that the chosen technological characteristics and the new middle layer extruder's design in the coextrusion equipment provide the formation of composite layers with the needed morphology and chemical composition as well as the necessary adhesion between the layers.