▎ 摘　　要

Graphene oxide nanoribbons (GONRs), as a new member of carbon family, attracted extensive attention in industry and science field. It has considered to be as a promising nanomaterial for applications in the field of materials science, energy storage and optics science due to its extraordinary mechanical, electrical and thermal properties. Hence, in this study, we carried out a facile and efficient strategy for preparing poly (phenylene benzobisoxazole) (PBO)/GONRs(PGR) composite fibers via one-pot in situ polycondensation method for enhancement in mechanical and thermal properties. The GONRs sheets in this work were obtained by unwrapping multi-walled carbon nanotubes (MWCNTs) side walls, and then directly reacted with PBO monomer 4,6-diaminoresorcinol(DAR) and covalently grafted on PBO molecular chains. The structure and morphology of GONRs and modified GONRs were well demonstrated by the FT-IR, XPS and TEM analysis for confirming the formation of chemical bond between GONRs and PBO molecular chains. The mechanical and thermal properties of PGR composite fibers were also investigated. It was found that the performance of composite fibers about 32.1% improvement in tensile modulus, 24.2% in tensile strength and 10.5% thermal stability, respectively.