Graphene oxide particles as an intrinsic oxygen source and template for improved carbon fibre production.

• Applicant: Dr. Christian Eberhard Halbig
• Subject Area: Synthesis and Properties of Functional Materials ; Solid State and Surface Chemistry, Material Synthesis ; Polymer Materials
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 558321509

Due to their high strength and chemical resistance, carbon fibres (C-fibres) are used in many areas of application where weight saving, emission reduction, durability or strength are important. The demand for these materials is constantly increasing, which makes research into CFRP an important field. C-fibers are mainly produced by wet spinning polymer solutions based on polyacrylonitrile (PAN) and subsequent thermal conversion (stabilization or oxidation in air at 200-300 °C and subsequent carbonization in the absence of oxygen at 900-1600 °C). However, this process is very energy-intensive, with stabilization accounting for around 56% of the costs of the entire thermal conversion. The aim of this project is to accelerate the stabilization process by introducing an intrinsic oxygen source into the raw PAN fiber and thus enable a more energy-efficient stabilization process. For this purpose, we primarily want to use various graphene oxide (GO) derivatives, as these can release reactive oxygen species (RSS) in the temperature range mentioned. From the data obtained, we want to derive the basic chemical-structural relationships, mechanistically investigate the reactions taking place between PAN and RSS and also find out how the template effect of in-situ formed graphene can help the thermally converted polymer to achieve higher strength. The following questions arise from the project approach: a. What is the best method to disperse GO particles homogeneously in a PAN-based polymer solution or PAN matrix? b. What must the GO be like in order to release RSS in the ideal temperature range for a successful conversion reaction? c. Can GO hybrid materials with other oxygen-rich additives improve the provision of RSS? d. Can in situ formed graphene further serve as a template for improved crystallization of the subsequent C-fiber? e. What effects do the modified processes have on the mechanical properties of C-fibers? The incorporation of GO into PAN-based structures prior to wet spinning of the actual fibers represents an under-researched approach in CF research. Furthermore, the approach of controlled in-situ generation of RSS for stabilizing raw fibers is unique. The research results are achieved using the latest physical and chemical characterization methods and should not only contribute to solving technical problems, but also to understanding the thermal conversion processes and enable a more environmentally friendly production of CF.

• DFG Programme: Research Grants