Successful proposals will contribute to the implementation of the EU Bioeconomy strategy, the Circular Economy Action Plan, the Sustainable Products Initiative (SPI), as well as the New European Bauhaus initiative and the EU Industrial Strategy.

Project results should contribute to the following expected outcomes:

• Availability of sustainable and circular bio-based composites meeting high technical performance requirements;
• Improved circularity and overall sustainability of downstream sectors taking into account both the production and use phase, as well as end of life considerations of composites;
• Significant improvement of environmental performance across the value chain against specified fossil and/or bio-based benchmarks;
• Improved circularity and resource efficiency via practical application of the circular (bio)economy concept;
• Facilitation of market uptake of scalable bio-based solutions.

Many sectors applying composites in their products have set a target of shifting from fossil-based towards bio-based and/or materials with a high recycled content. Current commercial bio-based polymers and natural fibre-based materials are however suited to respond only to a part of the projected increased demand. Limitations include not being fully compatible with current industrial processing, not being able to fully meet target application requirements, and/or their higher cost vs existing solutions.

Like conventional polymer matrices for composites, bio-based matrix materials can be divided into two different polymer groups of: i) thermoplastics and ii) thermosets. Thermoplastic polymers are characterised by reversible chemical bonds while thermosets have strong covalent bonds and crosslinking (aspects that may impact their recyclability). Regarding bio-based composites, demonstration activities have mainly focused on the integration of (natural or synthetic bio-based) fibres in fossil-based polymer matrices up to now, rather than fully bio-based composites (i.e. including both bio-based matrix and fibres).

Processability during manufacturing (including aspects of thermal stability), technical performance of the end product along its life cycle, and durability are some of the key challenges to address for bio-based composites. It is also important to address the end of life and circularity challenges of composites, including recycling, re-using or upcycling.

Proposals under this topic should:

• Demonstrate, at a relevant scale, the production of bio-based^[1] composite materials and products made from bio-based natural (e.g. plant) fibres and/or bio-based synthetic fibres (e.g. lignin carbon fibres), in bio-based thermoset and/or thermoplastic matrices. Proposals can address one or more classes of fibres and matrices depending on the application(s) and products in scope.
• In addition to the demonstration of the innovative composite end product, proposals may also include demonstration of the production of innovative fibres, matrix or both, as well as full formulation with relevant innovative bio-based additives where applicable.
• Meet end-product technical performance requirements dictated by the final application (e.g. mechanical and thermal stability properties, fire resistance, corrosion resistance, durability…).
• Design for sustainability and with a focus on enabling circularity to address major challenges of end of life in end use sectors. Circularity aspects can include also considerations in increasing the recyclable content, biodegradability and/or compostability (under specified conditions). The choice of the end of life option must be compatible with application and technical performance requirements. In case of recycling, the recycling routes for the composite materials in scope should be tested and a strategy should be proposed on the basis of existing practices and infrastructures.
• Address composites manufacturing issues, minimising CAPEX impacts, employing energy- and resource-efficient processes and minimising the amount of hazardous substances used in production.
• Include a task to integrate assessment based on the safe-and-sustainable-by-design (SSbD) framework, developed by the European Commission, for assessing the safety and sustainability of chemicals and materials^[2]. Under this context, projects are expected to contribute with and develop recommendations that can advance further the application of the SSbD framework^[3].

Proposals must implement the multi-actor approach and demonstrate the involvement of all concerned key actors in the bio-based systems, such as researchers and technology providers bio-based processing industries, end-users and consumers (in case of B2C^[4] value chains).

Proposals should also describe their contribution to the Specific CBE JU requirements, presented in section 2.2.3.1, and the Cross-cutting elements, highlighted in section 2.2.3.2 of the CBE JU Annual Work Programme 2023^[5].

Proposals should consider synergies with past and ongoing projects^[6].

[1] In the context of this topic, bio-based is considered as having at least 95% of organic carbon content from bio-based sources (measured using the C 14 method as defined in EN 16640:2017)

[2] See documents defining the framework and criteria on: https://ec.europa.eu/info/research-and-innovation/research-area/industrial-research-and-innovation/key-enabling-technologies/advanced-materials-and-chemicals_en.

[3] More specifically, provide thresholds that can support the criteria definition and improvements for the assessment SSbD methodologies, including any specificities related with bio-based surfactants. Recommendations should also include identification of data gaps, especially safety, environmental, but also socio-economic factors, as well as priorities for data collection.

[4] for a description of the term, see annex Glossary in the CBE JU Annual Work Programme 2023 (https://www.cbe.europa.eu/reference-documents)

[5] CBE JU Annual Work Programme 2023 (https://www.cbe.europa.eu/reference-documents)

[6] Proposals should consider ongoing and past projects, especially under BBI JU/CBE JU as well as H2020 but also HEU (Cluster 4 and 6). E.g. topic HORIZON-JU-CBE-2022-RIA-03 “Circular-by-design bio-based materials to improve the circularity of complex structures”, HORIZON-CL6-2023-CircBio-01-8: Eco-friendly consumer products – low-toxicity/zero pollution construction bio-based materials, BBI projects BIZENTE, VIBES, SSUCHY, ECOXY