Vol. 55 No. sp. is. 1 (2023): Vol. 55, special issue 1, 2023: In memoriam to the late Prof. Dr. Yusuf YAĞCI (1952-2023)
ITU ARI-A Natural Sciences

Mechanical Recycling of PET– Current Situation and Perspectives

Yonca Alkan Goksu
Istanbul Technical University

Published 04/01/2024


  • PET recycling,,
  • mechanical recycling,
  • chain extenders,
  • PET

How to Cite

Alkan Goksu, Yonca. 2024. “Mechanical Recycling of PET– Current Situation and Perspectives”. ITU ARI Bulletin of Istanbul Technical University 55 (sp. is. 1):45-52. https://ari.itu.edu.tr/index.php/ituari/article/view/77.


The exponential rise in global petroleum-based polymer production and consumption presents a significant environmental challenge, with projections indicating an alarming growth in annual plastic waste to 460 million tons by 2030. Despite the widespread use of poly(ethylene terephthalate) (PET) for its economic appeal and versatility, the accumulation of PET waste calls for urgent and effective recycling strategies. The critical importance of PET recycling to reduce environmental impact is emphasized by current worldwide efforts, such as restrictive laws imposed by the EU and the specific material limits implemented in countries like South Korea and Japan. While several mechanisms are employed for PET recycling, mechanical recycling emerges as a standout approach due to its industry applicability. However, challenges arise from PET degradation during reprocessing, necessitating innovative solutions. In this context, diverse chain extenders, including oxazolines, isocyanates, anhydrides, epoxides, and the promising Meldrum's acid derivatives, have been explored. These agents exhibit significant potential in improving the characteristics of PET throughout the recycling process, providing an avenue to reduce the environmental impact of plastic waste. This comprehensive perspective explores the current status and future potential of PET recycling. The combination of global initiatives, mechanical recycling innovations, and advanced chain extender strategies pave the way for a more sustainable and environmentally conscious future in polymer recycling.


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