An overview of the challenges and trade-offs in closing the loop of post-consumer plastic waste (PCPW): Focus on recycling.

Recycling of post-consumer plastic waste (PCPW) is increasingly promoted as the means to achieving circular economy (CE). It converts plastic waste into a secondary material that can be fed back into the system, for use in the same or new components and products, with similar or lower functionality; hence "closing the loop". Up until today, research on examining the environmental impacts, economic implications and technicalities of plastic waste recycling deals with one particular aspect, or stage on the plastic value chain, lacking coherence and structure. To move this research forward, understanding the challenges and trade-offs in scaling up plastic waste recycling is necessary. Here, we bring together existing literature on the multi-faceted aspects of closing the plastic loop, critically debating on the multi-stakeholder endeavours of promoting circularity in the plastics value chain. We present an overview of how the design, production, collection and sorting of PCPW present challenges for plastic waste recycling, which in turn result to a number of trade-offs. We explain that the evaluation of the multi-dimensional implications of trade-offs arising from the PCPW recycling, is essential in measuring the long-term sustainability of resource recovery from waste systems. This work scrutinises the sustainability of closing the plastic waste loops and sets a future research agenda.