Durobast

The use of natural fibers holds great potential for the sustainable and resource-saving design of structural components. As regionally available raw materials, bast fibers such as hemp and flax fibers not only provide an energy-efficient alternative to conventional glass or carbon fibers, but also contribute to a reduced CO2 footprint through optimized transport routes. The production of fiber reinforced polymer composites (FPR) with bio-based polymers, e.g. polylactic acid (PLA), enables the future-oriented production of structural natural FPR components, which also takes recycling at the end of the product life cycle into account. The Durobast project covers the entire process chain, from the selection of suitable natural fibers to component production by manufacturers. A particular focus is on fiber pre-treatment by cavity polymerization, which is intended to reduce moisture absorption. The Leibniz-Institut für Verbundwerkstoffe investigates the manufacturing of natural fiber reinforced organo sheets and the processing of these flat semi-finished products into final part geometries through thermoforming. It is of paramount importance in these processes to minimize the thermal influence on the fibers. Draping behavior is investigated in a shear frame test setup. A finite element model is created based on the results of these tests to determine the process design and to allow part manufacturing at minimal temperatures, while simultaneously minimizing stresses within the reinforcement textile to prevent draping defects of part distortion. The project Durobasts pursues a holistic approach to the manufacture natural fiber reinforced composites by combining pretreated natural fibers and bio-based polymers to enable future-oriented production.