Effect of mandrel rotation speed on morphology and mechanical properties of polypropylene pipes produced by rotational shear

• Published in: Journal of polymer research Vol. 28; no. 2
• Main Authors: Wu, Junjun, Xie, Zexiang, Yang, Hao, Yang, Minghao, Shen, Kaizhi, Fu, Qiang, Gao, Xueqin
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 2021; Springer Nature B.V
• Subjects: Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Elongation; Hoops; Industrial Chemistry/Chemical Engineering; Mechanical properties; Morphology; Original Paper; Pipes; Polymer Sciences; Polypropylene; Rotation; Shear; Tensile strength; PP pipes; Tensile strength; Rotational Shear; Elongation at break
• ISSN: 1022-9760; 1572-8935
• DOI: 10.1007/s10965-020-02366-0

To research the role of mandrel rotation speed on the morphology and mechanical properties of polypropylene (PP) pipes, a self-made rotational shear system (RSS) was applied in this study to manufacture plastic pipes with improved hoop tensile strength through applying hoop shear on the pipes using a rotational mandrel. Morphology study results indicated that different morphologies of the PP pipes were produced when the mandrel rotated at 0 rpm, 2 rpm, 4 rpm, 6 rpm, 8 rpm and 10 rpm. The tensile strength and elongation at break of the pipes were found to increase rapidly with the rotation speed and the properties peaked at 6 rpm. At this speed, the tensile strength and elongation at break increased by 4.1% and 727%, respectively. The high mechanical and thermal performance of the pipe produced at 6 rpm was attributed to the grains begin to refine and the thickness of amorphous region increases throughout the pipe wall.