Abstract

The global environmental issues caused by plastic incineration are continuously increasing, along with the demand for polyethylene terephthalate (PET)—27 million metric tons of PET was demanded in 2020. Therefore, PET recycling has emerged as the core of the global circular economy. In particular, PET recycling methods are categorized into two pathways: mechanical and chemical recycling, wherein mechanical recycling is more efficient than chemical recycling. However, PET undergoes heat-induced degradations during mechanical recycling such as reduction in molecular weight (MW) and viscosity. Therefore, feasible methods are required to overcome such challenges. This article details the mechanical recycling process of PET using a chain-extending extrusion method. Accordingly, various chain extenders (CEs) were reviewed to identify their effects on recycled PET (rPET) properties and reactive extrusion processes. Moreover, we detailed the recent progress in the reactive extrusion method used for PET recycling based on the effects of various CEs on rPET properties.

摘要

塑料焚烧引发的全球环境问题不断增加，同时对聚对苯二甲酸乙二醇酯 (PET) 的需求也在不断增加——2020 年需要 2700 万吨 PET。 因此，PET回收已成为全球循环经济的核心。具体而言，PET回收方法分为机械回收和化学回收两种途径，其中机械回收比化学回收更有效。然而，PET 在机械回收过程中会发生热降解，例如分子量 (MW) 和粘度降低。因此，需要可行的方法来克服这些挑战。本文详细介绍了使用扩链挤出法对 PET 进行机械回收的过程。因此，审查了各种扩链剂 (CE) 以确定它们对回收 PET (rPET) 性能和反应挤出工艺的影响。而且，