The morphology and properties of recycled plastics made from multi-layered packages and the consequences for the circular economy

Abstract

Multilayer packaging, comprising layers of different materials, offers various advantages for the storage of products but poses challenges concerning its recyclability. The layers provide specific functionalities (strength, barrier properties) but their combination results in incompatibilities and layer inseparability, limiting recyclability. Sustainable designs for multilayers hold great potential to meet the European Union's recycling targets, as they account for up to 20% of flexible films. However, this study demonstrates that the majority of investigated packaging structures does not comply with current guidelines for sustainable packaging design. Contamination by polymers, especially the combination of polyethylene terephthalate with polyolefins, leads to embrittlement of the recyclate, making reprocessing into products of similar economic value impossible. Holistic design choices and material selection based on legal guidelines, management of expectations and profit margins, and harmonization of processes and product appearances to bridge the gap between design for and from recycling of multilayer packaging are suggested.