Fraunhofer Institute for Microstructure of Materials and Systems IMWSIn the “SkaNaPA” project, the Fraunhofer Institute for Microstructure of Materials and Systems IMWS in Halle (Saale) is collaborating with partners to develop natural fiber-reinforced biopolyamides for safety-critical automotive components. The goal is a lightweight, recyclable material made from renewable raw materials that replaces glass fibers and fossil-based plastics, complies with strict limits for odor and emissions, and can be processed economically on existing industrial equipment through to series production. The result is expected to be an injection-molding compound for applications in automotive interiors.
Glass-fiber-reinforced plastics are primarily used in automotive engineering where components must be significantly stiffer, stronger, and more temperature-stable than pure plastics, yet lighter than metal. Typical applications include structural parts behind visible trim (e.g., instrument panel supports), housings in the engine compartment, or seat components. Polyamide, which is produced from fossil raw materials, is frequently used as the plastic in these applications.
To better meet the requirements for climate protection and resource conservation, automotive suppliers aim to develop sustainable materials that are technically just as high-performance as established materials. This is where the “SkaNaPA” project comes in. The research team’s goal is a material that:
- consists of renewable raw materials,
- is mechanically stable enough for safety components,
- complies with the automotive industry’s strict limits for odor and emissions,
- and can be processed economically on standard industrial equipment.
The new material is to be tested in injection-molded components for automotive interiors, which will be manufactured using industrial injection molding at Fraunhofer IMWS and subsequently subjected to detailed performance testing. “We want to demonstrate how well sustainable materials can meet the automotive industry’s stringent requirements for safety, odor, and mass production,” says Dr.-Ing. Patrick Hirsch, group leader at Fraunhofer IMWS.
Instead of fossil-based raw materials, the project partners are relying on bio-based polyamides produced from renewable raw materials. Maximum sustainability is also being considered for the reinforcing fibers in the project, which runs through September 2027: Natural reinforcing fibers made from cellulose provide high stiffness and are significantly more climate-friendly to produce than glass fibers. The solutions are also intended to be scaled up from the laboratory level to industrial series production.
The research team places particular emphasis on systematically addressing odor and emissions as early as the development and processing stages. Measurement methods from the previous project – such as an emissions chamber directly attached to the extruder – are now being applied to larger-scale systems. This allows for early identification of which process settings will result in the lowest possible emissions of volatile organic compounds (VOCs) during subsequent use in the vehicle. Another key component is direct compounding injection molding (DCIM) technology. Here, the material is mixed in a single step and directly processed into a component. The lower thermal stress can reduce odor formation and preserve the material.
The Fraunhofer IMWS contributes its particular strengths in the scaling of plastics processes and industry-relevant testing:
- Operation of twin-screw extruders from the laboratory to industrial scale at the Fraunhofer Pilot Plant Center PAZ in Schkopau
- Transfer of laboratory results generated at the University of Kassel to extruders with significantly higher throughput (up to at least 100 kg/h) and later to industrial scale at the industrial partner Exipnos GmbH (Merseburg)
- Injection molding trials on large machines (up to 3200 t clamping force), including existing molds
- Mechanical testing of materials and components (strength, stiffness, impact resistance) as well as microstructural analysis.
“At Fraunhofer IMWS, we can test new materials under realistic industrial conditions – from formulation development to large-scale injection-molded components,” says Hirsch. “This allows us to bridge the gap between basic research and marketable solutions for the plastics and automotive industries.”
These capabilities and the close collaboration among project partners are essential because the combination of natural fibers and bio-polyamides is technically challenging. For instance, polyamides are processed at relatively high temperatures, while natural fibers are sensitive to heat. A narrow “processing window” must therefore be identified in which the fibers do not degrade, yet the material still flows well and retains its shape. During scale-up, process parameters such as temperature profiles, shear stress, and residence times in the extruder change – they influence both the mechanical properties as well as odor and emissions. Additionally, strict limits set by automotive manufacturers for volatile organic compounds (VOCs) and odor notes must be adhered to. These relationships are systematically investigated in the project to define robust processes and material formulations.
The results provide industry suppliers with specifications and validated process windows for natural-fiber-reinforced bio-polyamides used in vehicle interiors. The application partner Exipnos can bring new, sustainable compounds to market – initially for seat structures, and later for other interior components. With “SkaNaPA,” the Fraunhofer IMWS, together with its partners, is thus making a decisive contribution to ensuring that bio-based, natural fiber-reinforced plastics make the leap from the laboratory to automotive series production – thereby combining ecological and economic goals.
The research project is funded by the German Research Foundation (DFG) as a trilateral transfer project.
(March 16, 2026)