Properties of recycled polymer mixtures obtained in the screw-disc extrusion process
Polimery 2011, No 2, 135
Quantitative and qualitative mixtures of recycled polymers (PE-LD, PE-HD, PP, PS) have been prepared using a home-made screw-disc extruder and their properties studied (Table 1, Fig. 2). The extrudates obtained at clearance between the screw face and cylinder head ranging from 0.3—3.0 mm were evaluated on the basis of the degree of homogeneity in the cross-sectional and longitudinal areas (Figs. 3—6). The influence of the dimension of the clearance between two conical discs, a movable end face of a screw and a stationary cylinder head, on mechanical properties such as the unit elongation and stress of the obtained extrudates was also determined (Figs. 7 and 8). The results confirm, that in the case of elastic materials obtained by using a large content of polyethylene, the most adequate dimension of the clearance die in the applied screw-disc extrusion process is 1 mm.