Part 1/3: TPE as Part of Polyolefin Recycling Streams

Regardless of their specific characterization as Styrene Block Copolymer Compounds (TPS), thermoplastic polyolefins (TPO), vulcanisates (TPV) or polyurethanes (TPU), thermoplastic elastomers (TPE) are not recycled in separate material streams. As ‘soft’ components in multi-material packaging products, their share is rather small compared to that of ‘hard’ plastics such as polypropylene or high-density polyethylene (HDPE).

In response to concerns regarding the co-recyclability of TPE together with PP or HDPE, KRAIBURG TPE started a project together with Institut cyclos-HTP to investigate the compatibility of selected TPS in polyolefin recycling streams and their potential impact in the process on the resulting post-consumer recycle (PCR).

The tests focused on classical TPS formulations with densities of <0.95 g/cm³ as used in typical multi-material packaging applications with PP and HDPE. The density limitation ensures that any components with higher densities would be removed from the main material stream and could not enter the next process step. In addition, the test program was engineered to extend to a wide range of further TPE, as required.

In view of concerns regarding the feasibility of TPE as part of circular polyolefin solutions, we started a project in 2020 to proof the compatibility of selected TPS materials with PP and HDPE recycling streams. Together with Institut cyclos-HTP as independent project partner, we worked to establish a solid scientific basis for evaluating and redefining the co-recyclability of TPE.

The result: Appropriate certificates of co-recyclability in PP and HDPE recycling streams are publicly accessible and can be downloaded for each compound in the database from our website.