Preparation of PPR/PS Blends by Multiflow Vibration Injection Molding: Influence of Shish–Kebab Structures and In Situ Fibers

Abstract

PPR resin has the advantages of good transparency, high impact strength, and low welding temperature and is widely used in pipelines, automobile parts, furniture, and packaging. However, a low tensile strength limits its application in other fields. In this work, PS is chosen to modify PPR, and multiple shear fields are exerted on the polymer melt during the packing stage. The results demonstrate that PS forms in situ fibers, and a large number of shish−kebab and hybrid shish−kebab structures can be detected. Compared with the conventional injection-molded sample, the crystallinity increases from 32.9 to 35.8% and the tensile strength increases from 18.37 to 47.22 MPa. Meanwhile, the impact strength remains as high as 28.04 kJ/m 2 . This work achieves excellent comprehensive mechanical properties of PPR, and it is of great theoretical and practical significance for its broad application.