Periodic Reporting for period 2 - REPurpose (Recyclable Elastomeric Plastics safely and sUstainably designed and produced via enzymatic Recycling of Post-cOnsumer waSte strEams)
Reporting period: 2024-03-01 to 2025-08-31
As such, REPurpose will deliver a platform of waste-based, recyclable polymers and products with adjustable functional properties for hard-to-recycle applications in the consumer goods, construction and automotive industry. The project adopts a cross-sectorial value chain approach, involving waste handlers, regulators, specialty material producers, technology developers, and end users. The project will compile best practices and contribute to SSBD criteria development as well as shaping policy recommendations.
In conclusion, the transformative potential of the REPurpose initiative presents an opportunity to address the escalating challenges posed by the increasing global consumption of materials, particularly in the field of plastics.
In parallel, several enzymes were characterised, selected, and produced at lab and pilot scale to depolymerise different types of pretreated plastic waste into similar building blocks, now used in recycling trials.
Further down the chain, a broad library of new REP polymers was developed using commercial and validated waste-based building blocks. These polymers were characterised for their functional properties, incorporating feedback from application developers and end users. Selected formulations were scaled up, and toxicity testing confirmed their safety for human health and the environment. Some REP polymers were compounded with natural fibres and processed using industrial techniques. Technical requirements were defined, and product design for targeted applications is ongoing.
Efforts focus on ensuring REP polymers and products are reusable, recyclable, and sortable from other plastics at end-of-life. A spectral detection method was validated for REP identification in industrial sorting, with successful sorting trials supporting practical recovery.
Key innovations were identified for business exploitation. Communication efforts included updated materials, a promotional campaign, editorial publications, and dissemination at numerous events, including collaborations with Sister and Cousin projects.
Life cycle, techno-economic, and social assessments are underway to evaluate sustainability, fully integrating the SSbD concept. An inventory of potentially toxic plastic additives was compiled, and compliance with existing regulations is ensured. A regulatory framework with policy recommendations, initial guidelines, and a technology trends report were developed. Industry input was collected via questionnaires, and work continues on a draft for a new recycling-related standard.
In parallel, enzymes for depolymerising pretreated plastic waste into similar building blocks were designed, selected, and produced at up to 150 L scale. Work is ongoing to upscale plastic depolymerisation processes.
Commercial analogues of waste-based monomers and one actual waste-based monomer have been polymerised into REP prototypes. By varying building block functionality, chain length, and polymerisation conditions, 26 REP prototypes with diverse architectures and functional properties were developed. One REP grade matched properties of Hytrel® (partly biobased); others showed more rigid yet processable profiles. Several have been selected for scale-up, with optimisation underway. Final validation using actual waste-based monomers will confirm the robustness of the REPurpose concept.
Technical requirements (durability, mechanical properties) have been defined for targeted applications (construction, automotive, consumer goods/sportswear). REP materials, both rigid and elastic, were tested in various processing techniques (sheets, injection moulding, 3D printing, foaming, extrusion). Initial product prototypes were made from commercial materials, with REP-based prototypes to follow. REP compounds with natural fibres have also been produced.
While REPurpose covers activities up to TRL 5, further development, demonstration, and market entry will require additional public or private funding.
Transversal activities include:
- Ensuring REACH/CLP compliance and proposing relevant framework conditions;
- Creating a public inventory of plastic additives for safe, biobased selection;
- Analysing spectral data to support REP identification during sorting;
- Conducting social, environmental, and economic assessments to guide development;
- Promoting Responsible Research and Innovation and Open Science within the consortium.