Covalent treatment of carbon fibre with functionalized MoS2 nanosheets using thiol-ene click chemistry: The improvement of interface in multiscale epoxy composites

Abstract

The multiscaling method is contemplated as an effective approach for improving the interfacial adhesion in carbon fibre composites. Nonetheless, the lack of interactions between the nanomaterials and the other constitutes including fibre and matrix resulted in the deterioration of mechanical performance in composites. Herein, the combination of a scalable synthesis method based on ball milling and thiol-ene click chemistry has been utilized to graft the functionalized MoS 2 nanosheets with large lateral dimensions (∼537 nm) on the carbon fibres surface for the first time. The proposed method did not significantly affect the mechanical properties of the carbon fibre, leading to augmentation in the performance of composites by the virtue of higher surface energy and roughness of the fibre surface. In other words, the obtained results have demonstrated that the presence of activated MoS 2 nanosheets on the carbon fibre surface possesses the ability to promote interfacial adhesion and interlaminar shear strength by 74% and 36% respectively, compared to the pristine unsized carbon fibre. Additionally, the effectiveness and the efficacy of MoS 2 -CF reinforcements can be delineated by the enhancements of flexural strength and modulus of multiscale composites by 49.5% and 33.6%, respectively. The morphology of both fibres and fractured surfaces of composites indicated that the random distribution of nanosheets on the fibre surface facilitates the energy dissipation via breakage, pullout, and bridging mechanisms which subsequently improved the overall performance of the developed composites.