Interfacial effects of carbon nanotube-modified epoxy on PBO Fiber composites: Quasi-static and dynamic mechanical properties

PBO ( p -phenylene benzobisoxazole) fibers demonstrate considerable potential for application in various engineering fields. Nevertheless, their surface, which is excessively smooth, significantly impedes their properties. In this paper, PBO single-fiber reinforced composites were prepared by coating and modifying PBO fibers after oxygen plasma treatment using different concentrations of carbon nanotube-modified epoxy resin (EP/CNTs). The results show that the O/C ratio of the PBO fibers increases and structures such as epoxy/bisphenol are introduced after coating the surface of the PBO fibers with resin. The interfacial shear strength (IFSS) increases with the concentration of the coated EP/CNTs, up to 65.34 MPa. The dynamic mechanical properties of the PBO fibers increase after the coating modification treatments, and the highest tensile strength achieves 8.8 GPa at a strain rate of 1100 s −1 . This work provides a feasible and efficient strategy to modify the surface of PBO fibers, achieving a better combination between resin and component fibers.