New materials from PET waste for technical applications
Plastic waste and improper handling of it lead to global environmental problems. Packaging plastics in particular are problematic if they are not returned to a further cycle of use. In the completed research project “UpcyclePET”, the Fraunhofer LBF together with Easicomp GmbH, an expert in long glass fibre reinforced thermoplastics, developed a new material based on used beverage bottles made of PET.
This new and sustainable material has mechanical properties similar to those of short glass fibre reinforced virgin plastics, such as short glass fibre reinforced polyesters or polyamides. The demonstrator component made from the new material is also characterised by low shrinkage and particularly high dimensional stability. In addition, the material has a significantly improved CO2 footprint, as determined by the project partner Öko-Institut in an orienting life cycle analysis. Equipped with these properties, the new materials have a high potential to be used especially for larger components in technical applications, such as in automobiles, in furniture or in the construction sector.
“The research project has shown where limits lie and where considerable potential still lies dormant,” explains Dr Tapio Harmia, Managing Director of Easicomp. “The special requirements of process chains with secondary raw materials, such as reliable and plannable availability in terms of quantity and quality, must be given special consideration,” adds Dr Volker Strubel, joint coordinator of the project. “Holistic solutions for high-quality recycling and upcycling are often sector- and application-specific. They therefore require that players along the value chain, for example processors, designers and users, be involved in developments at an early stage,” explains Dr Frank Schönberger, head of the “Polymer Synthesis” department at the Fraunhofer LBF.
In the follow-up project “UpcyclePETPlus”, the core partners with the waste disposal company Jakob Becker and the specialist for injection-moulded components, KS Innovation, will face two further central challenges in order to develop economically attractive and sustainable upcycling solutions.
On the one hand, secondary material flows are being addressed that entail significantly lower qualities and high quality fluctuations, such as PET-rich fractions from the dual system, which today essentially cannot be materially recycled. The project is therefore applying and further developing separation and purification processes to improve the quality of PET material streams.
On the other hand, the project partners have set themselves the goal of optimally designing the interface between material development and the manufacturing process of the component. Thus, LFT materials are being developed on selected PET material streams through customised blending and additives. Finally, the influence and interaction of fibre length, fibre and recyclate content as well as additives are specifically investigated with a view to the application-oriented properties of the manufactured component and the injection moulding process used for this is optimised.
The aim of “UpcyclePETPlus” is to make the components of PET packaging waste that have so far not been recyclable available for a high-quality technical application.
