LFT recyclate

Combination of LFT with post-consumer and post-industrial recyclates

For long-fibre-reinforced thermoplastics (LFT), established recycling routes that preserve fibre length are not yet available. The IKV project “LFT Recycling” addresses the question of how large-volume LFT components can be recycled at the material level and how high-quality recyclates can be reused. To investigate the material recyclability of long-fibre-reinforced thermoplastics (LFT), a pilot-scale processing chain was implemented, comprising plastification, compression moulding, component production, mechanical shredding, and reprocessing. Substantial fibre damage and shortening already occur during both shredding and plastification. Screw speed proved to be a key parameter. Furthermore, it can be inferred that during shredding, suitable classification enables removal of fine, heavily damaged fractions from the cycle to enhance material quality.

© IKV

Alongside material properties, a life cycle assessment (LCA) evaluated the environmental impacts of different processing routes. For the scenarios studied with 25% recycled content, the comparison with conventional processing routes indicates potential reductions in the environmental impacts covered by the LCA (Fig. 1). A key factor in these results is the assumed material recycling at end of life instead of energy recovery. The project thus shows under which of the conditions investigated LFT recyclate could partially replace virgin material. Challenges remain in maintaining consistent material quality, ensuring process stability at high recycled contents and processing contaminated post-consumer material streams. The findings provide a basis for investigating these questions systematically in future projects, including fibre-length-preserving processing methods and the combination of recyclates with recycled unidirectional tapes.

Project data and funding

We would like to thank the BMWE for funding the IGF project (funding code 22995 N) and the project partners for their cooperation.

Project duration: 01.11.2023 – 31.10.2025