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BY 4.0 license Open Access Published by De Gruyter August 1, 2019

The Influence of Mechanical Recycling on Properties in Injection Molding of Fiber-Reinforced Polypropylene

  • T. Evens , G.-J. Bex , M. Yigit , J. De Keyzer , F. Desplentere and A. Van Bael

Abstract

Due to higher mechanical demands on technical parts, the application of short fiber reinforced thermoplastics for injection molding is strongly increasing. Therefore, more attention needs to be paid to the optimization of their recycling processes. Mechanical shredding of thermoplastics into granules is a common recycling method within polymer industries. The breaking of polymer chains and reinforcing fibers during this process may affect the material properties. This study presents the effect of ten recycling sequences on four different materials: polypropylene, glass fiber filled polypropylene, carbon fiber filled polypropylene and flax fiber filled polypropylene. Tests indicate that recycling has a negative influence on most of the mechanical properties. Polypropylene without fibers forms an exception as it does not exhibit any significant change in material properties. Glass fiber and carbon fiber reinforced polypropylene show a decrease in stiffness and tensile strength during the recycling steps. The impact strength of carbon and flax fiber reinforced polypropylene increases whereas that of glass fiber reinforced polypropylene decreases.


*Correspondence address, Mail address: Tim Evens, KU Leuven, Diepenbeek Campus, Materials Technology TC, Wetenschapspark 27, 3590 Diepenbeek, Belgium, E-mail:

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Received: 2018-10-04
Accepted: 2019-02-15
Published Online: 2019-08-01
Published in Print: 2019-08-13

© 2019, Carl Hanser Verlag, Munich

This work is licensed under the Creative Commons Attribution 4.0 International License.

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