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Licensed Unlicensed Requires Authentication Published by De Gruyter November 7, 2013

Effect of the Mandrel Rotation Speed and Inner Wall Cooling Rate on the Performance and Structure of Polypropylene Block-Copolymer Pipe

  • R. Han , M. Nie , S.-B. Bai and Q. Wang


Polypropylene block-copolymer (PP-B) pipes were prepared using a self-designed rotational extrusion processing system. The experimental results showed that though the crystal morphology in the prepared PP-B pipes did not change compared to conventional extrusion, the molecular chains in amorphous region apparently deviated from the axial direction. As a result, in comparison with the conventional extrusion pipes, the mechanical properties in hoop direction and the resistance to crack growth of rotation extrusion PP-B pipes were greatly improved. Furthermore, both the two mechanical properties improved monotonously with increasing mandrel rotation speed and inner wall cooling rate.

Mail address: Qi Wang, State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University, Chengdu 610065, PRC, E-mail:


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Received: 2013-1-16
Accepted: 2013-8-17
Published Online: 2013-11-07
Published in Print: 2013-11-01

© 2013, Carl Hanser Verlag, Munich

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