Improving the interfacial property of CF composites through constructing multiscale interfacial nanostructures

Abstract

The performance of resin-based composite materials is closely related to their interfacial properties. Due to the significant difference in properties between carbon fibers (CFs) and polymer matrices, the interfacial bonding is very poor, and enhancing interfacial performance becomes an important direction for the development of composite materials. In this paper, multiscale nanostructures were constructed on the carbon fiber surface using the mixtures of trifunctional polyetheramine modified graphene oxide (T403-GO) and epoxy (EP) to improve the interfacial performance of CF reinforced EP composites. Depending on the types of the epoxy sizing resins (TDE-85, E−51, and E−44) and the amount of T403-GO, carbon fibers with different surface morphologies and interfacial layers with different mechanical properties are obtained. Benefiting from the multiscale nanostructures, both the wettability between CF and the polymer matrix and the IFSS of the composites are improved. Meanwhile, the enhanced mechanisms of the interfacial properties are also revealed. For E−44 containing 0.15 wt% of T403-GO system, the IFSS was increased up 75.61 MPa, which was 1.47 times that of the original CF. It is evidenced that constructing multi-scale structures on the surface of CFs is an effective method to improve interfacial performance, and sizing resin plays a critical role in the interfacial structure and performance.