Recycled Polypropylene for Food Contact: Technologies for Recycling, Modification, and Safety Evaluation

LIU Yiqi; LI Zekun; HU Changying

doi:10.19554/j.cnki.1001-3563.2025.19.010

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Packaging Engineering ›› 2025, Vol. 46 ›› Issue (19) : 82-92. DOI: 10.19554/j.cnki.1001-3563.2025.19.010

Advanced Materials

Recycled Polypropylene for Food Contact: Technologies for Recycling, Modification, and Safety Evaluation

LIU Yiqi¹, LI Zekun², HU Changying^1*

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Abstract

The work aims to review the recycling and modification technologies of recycled polypropylene (rPP), as well as its safety when it is used as food contact material, so as to provide reference for the application of rPP in food contact materials in China. The latest research on rPP recycling technologies, modification methods for rPP used as food contact materials, and their safety evaluation in China and abroad was summarized and analyzed. Physical recycling is an effective approach to mitigate the environmental impact of waste PP. However, rPP experiences performance degradation during the recycling process due to factors such as thermomechanical degradation, resulting in reduced molecular weight, decreased viscosity, and poorer mechanical properties. Significantly, the performance of rPP products can be substantially improved by incorporating processing aids, nanoparticles or glass fibers, polyolefin blends, and bio-based materials. These modifications also help reduce the migration of harmful substances, thereby enhancing the safety of rPP for food contact applications. Furthermore, chemical recycling and biological recycling hold significant development potential. With performance modification and optimized product formulations, rPP holds promise for further expanding its application in the field of food contact materials, which has increasingly stringent safety requirements.

Key words

recycled polypropylene / recycling technology / food packaging / safety

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LIU Yiqi, LI Zekun, HU Changying. Recycled Polypropylene for Food Contact: Technologies for Recycling, Modification, and Safety Evaluation[J]. Packaging Engineering. 2025, 46(19): 82-92 https://doi.org/10.19554/j.cnki.1001-3563.2025.19.010

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