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Licensed Unlicensed Requires Authentication Published by De Gruyter April 10, 2017

Time Dependence of Morphology and Mechanical Properties of Injection Molded Recycled PET

  • B. Molnár and F. Ronkay


During research, injection molded samples were prepared from recycled poly(ethylene-terephthalate) granulate, and their mechanical properties were investigated as a function of time. To understand the changes in mechanical properties, both morphology of injection molded samples and recycled granulates were investigated. A three-phase morphological model was applied for the evaluation of morphological properties while mechanical properties were determined by tensile and impact tests. Relationship was found between morphological and mechanical characteristics as a function of time elapsed since production. Crystalline ratio, tensile strength, and modulus of injection molded specimens increased while impact strength decreased in the four weeks after production.

*Correspondence address, Mail address: Ferenc Ronkay, Department of Polymer Engineering, Faculty of Mechanical Engineering, Budapest University of Technology and Economics, H-1111 Budapest, Műegyetem rkp. 3, Hungary, E-mail:


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Received: 2016-05-23
Accepted: 2016-09-08
Published Online: 2017-04-10
Published in Print: 2017-05-28

© 2017, Carl Hanser Verlag, Munich

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