Plastics have fundamentally improved modern living, yet their short life cycle and the sheer volume of resulting waste have triggered a global environmental crisis. Polyethylene terephthalate (PET) is the most widely used plastic for beverage packaging. While clear PET bottles are successfully mechanically recycled back into new bottles, the same cannot be said for mixed-color, or opaque PET streams. Because these colored plastics have high compositional variation and lower aesthetic appeal, they suffer from low industrial demand. Consequently, this "orphan" waste stream is frequently downcycled into fibers, sent to landfills, or incinerated, breaking the loop of the circular economy.
The R-PETFOAM project was born to solve this exact problem. The overall objective was to upcycle these undervalued, mixed-color PET waste streams into high-performance, high-value structural foams. Polymeric foams are lightweight, rigid materials filled with tiny gas bubbles, widely used as the structural core in wind turbine blades, aerospace components, as well as construction and automotive panels. Because foams are inherently opaque, the variable color of the plastic waste become completely irrelevant.
The project's pathway to impact relies on replacing toxic, highly polluting, or expensive virgin core materials (like PVC or virgin PET foams) with a 100% recycled alternative, processed using an eco-friendly blowing agent: supercritical carbon dioxide (scCO2). By demonstrating that mixed-color waste can be transformed into a premium engineering material, R-PETFOAM aims to create a lucrative market pull. Valorizing just a fraction of Europe’s undervalued colored PET waste could generate millions in revenue while drastically reducing the carbon footprint of both the waste management and composite manufacturing sectors.
