Enhancing thermal conductivity and flame resistance of carbon fiber composites using CNT-infused multiphase graphene resins

Carbon fiber composites (CFC) are distinguished by their remarkable strength-to-weight ratio, rendering them exceptionally suitable for various applications. This study explores replacing the conventional polymer epoxy matrix in CFCs with macropore-infused graphene nanocomposite emulsion thermosets (MINETs) based on easily sourced materials. The explored MINETs are formed from epoxy resin, graphene particles, and different oils as working fluids. This approach allows CFCs to exhibit multifunctional properties, including enhanced thermal conductivity and flame resistance, making them ideal for fire-proof drone enclosures, electronic casings, and thermal-energy-storage equipment applications. The thermal conductivity was further increased by adding carbon nanotubes (CNT) to the MINET matrix. The rheological properties of MINET allowed for CNT loading concurrently alongside graphene, without preventing processing. Rheological evaluations and Vickers hardness assessments were conducted to optimize the maximum CNT loading for efficient molding and robust mechanical properties. Thermal conductivity analysis demonstrated that CNT-reinforced MINET composites have a higher thermal conductivity when compared to standard graphene-MINET formulations. Infrared thermal imaging confirmed that CFC MINET composites have better dynamic heat transfer properties than CFC epoxy samples. Flammability tests indicated an improved flame resistance, particularly for silicone oil CFC MINET CNT formulations. The results indicate that CNT-infused CFC MINET exhibits exceptional thermal management and enhanced fire resistance co-optimized with mechanical properties, thus rendering it ideal for high heat dissipation, thermal stability, and flame retardancy.