Against the background of resource scarcity and the drive to increase raw material productivity, raw materials, manufacturing processes and the subsequent recycling of materials play an essential role. FRPs based on renewable raw materials are generally characterized by a lower CO2 footprint over the entire product life cycle compared to conventional, petroleum-based materials.
Based on benzoxazines, chemically, mechanically and thermally stable and even bio-based polymers are accessible. Phenolic components, amines and formaldehydes are required for benzoxazine synthesis, and these components can be obtained from conventional petroleum products, but also from renewable raw materials such as corncobs or sesame seeds. In the "GreenLight"-project, research will be conducted into sustainable benzoxazine-based composites in terms of sustainable chemistry. In this context, special attention will be paid to environmental and social factors in the selection of raw materials (origin, extraction, etc.) as part of a sustainability analysis.
In order to further reduce the CO2 footprint, there is also the task of achieving the longest possible life cycle or service life for these materials. To achieve this goal, the fiber-reinforced plastics are equipped with sensors that allow the condition of the materials to be monitored during operation. With this security, the design of the materials in production can be improved and the number of maintenance cycles as well as the maintenance effort can be reduced.
The sensors can be integrated by inserting film-based or printed sensors in the form of pastes. As part of the "GreenLight"-project, these approaches will be applied to bio-based polybenzoxazines with basalt fiber reinforcement. In addition, concepts will be developed by which data from the sensors can be used for structural health monitoring (SHM). These data also form the basis for a digital twin that maps the material over its entire life cycle (design, creation, operation and recycling) and can be used to evaluate long-term properties.
In particular, the high-performance plastics, such as the benzoxazine-based materials to be researched here, have a high value-added potential as a material upgrading can be reached when they are recycled in alternative applications. Recycling existing materials or even components reduces the use of raw materials. However, this presupposes that the components can be dismantled into materially pure components for further material use. Against this background, the topic of recycling-friendly design concepts for dismantling material composites at the end of life or for a necessary repair during the service life is of importance.