Post-Consumer Resin - Understanding the quality-performance linkage for packaging

家庭和个人护理产品通常装在高密度聚乙烯（HDPE）制成的瓶子中，每年生产约15万吨这种包装。然后收集、分类和机械回收所产生的消费后塑料。这种机械回收过程包括研磨，洗涤，然后挤出，得到称为消费后树脂（PCR）的颗粒。每年生产的HDPE PCR不到69，000吨，这意味着超过一半的塑料包装将被填埋而不是回收。PCR可用于HDPE包装，以取代原始塑料，从而节省浪费，并且在碳排放方面也更有效。然而，在包装中使用PCR的主要问题之一是它是一种可变材料。它可能含有不同等级的塑料，可能被其他材料污染，回收过程本身可能导致塑料降解。这意味着将PCR掺入瓶中往往会导致包装性能降低。PCR的可变性使得公司更难在包装中使用PCR，它增加了使用PCR的成本，并最终对PCR的增加使用产生经济惩罚。目前对HDPE在回收过程中发生的变化缺乏充分的科学认识，这意味着解决PCR不一致的问题具有挑战性。这意味着迫切需要了解包装中PCR的质量-性能联系。这个雄心勃勃的项目汇集了来自利物浦大学和曼彻斯特大学的跨学科团队，以改善HDPE的机械回收。我们将通过利用现有的塑料和基础设施，在2025年前实现塑料公约关于这一重要废物流的目标，减少塑料废物并增加回收利用。我们将详细了解PCR的化学和性质关系。这一新知识将使生产的PCR在包装方面具有更好的性能，并防止在回收过程中降解。同时，我们将了解这种PCR供需中断将如何影响供应链。这一认识将有助于选择能够带来最大经济、社会和环境效益的干预措施。因此，这项研究将有助于提高包装中PCR的质量，增加PCR的价值，从而推动塑料回收的更多投资。

Home and personal care products are often contained in bottles made of high-density polyethylene (HDPE) and about 150,000 tonnes of this packaging are produced annually. The resulting post-consumer plastic is then collected, sorted and mechanically recycled. This mechanical recycling process involves grinding, washing and then extruding to give pellets known as post-consumer resin (PCR). Less than 69,000 tonnes of HDPE PCR are produced annually, which means that more than half of the plastic packaging is going to landfill rather than being recycled. PCR can be incorporated into HDPE packaging to replace virgin plastic which saves on waste and is also more efficient in terms of carbon emissions. However, one of the major issues with using PCR in packaging is that it is a variable material. It may contain different grades of plastic, it can be contaminated with other materials and the recycling process itself can lead to degradation of the plastic. This means that incorporation of PCR into bottles tends to result in reduction in performance of the packaging. The variability in PCR makes it harder for companies to use PCR in packaging, it increases the cost of using PCR and ultimately places an economic penalty on the increased use of PCR. There is currently insufficient scientific understanding of the changes that occur to HDPE during recycling which means that it is challenging to address issues with the inconsistency of PCR. This means there is an urgent need to understand the quality-performance linkage for PCR in packaging.This ambitious project brings together an interdisciplinary team from the University of Liverpool and University of Manchester to improve the mechanical recycling of HDPE. We will enable rapid delivery towards the goals of the Plastic Pact for this important waste stream, and reduce plastic waste and increase recycling by 2025, by making use of existing plastics and infrastructure. We will generate a detailed understanding of the chemistry and property relationship of PCR. This new knowledge will allow PCRs to be produced with improved performance in packaging and also to prevent degradation in recycling. Simultaneously, we will understand how this disruption within the supply and demand for PCR will impact supply chain. This understanding will allow interventions to be selected that deliver the greatest economic, social and environmental benefits. This research will therefore facilitate improving the quality of PCR in packaging, increasing the value of PCR which will then drive greater investment in plastics recycling.