Properties of poly(p‐phenylene benzobisoxazole) fiber, and advances in its surface modification to enhance fiber–matrix adhesion: A review

Abstract

High‐performance polymer fibers, commonly used as reinforced fibers, have garnered significant attention across various scientific and industrial domains due to their extremely high tensile strength and excellent toughness. Notably, poly(p‐phenylene‐2,6‐benzobisoxazole) (PBO) fibers are hailed as the most advanced high‐performance fibers of the twenty‐first century, known for their exceptional mechanical properties, outstanding thermal stability, excellent flame retardancy, and chemical resistance, attracting considerable attention and favor from researchers. This review provides a comprehensive overview of the structure of PBO fibers and two synthesis methods of PBO polymers, detailing the properties of PBO fibers to offer valuable references for researchers in this area. This review highlights various techniques for modifying PBO fibers. Conventional methods can easily damage the structure of PBO fibers, resulting in difficulties in achieving the ideal mechanical properties of the corresponding composites. Surface coating modification can improve the surface roughness and reactivity of PBO fibers without compromising their structure. Additionally, the enhancement of interfacial compatibility for PBO fiber‐reinforced composites via introducing interfacial compatibilizers is analyzed in detail. Finally, the challenges and future prospects of PBO fibers are also discussed. This paper aims to provide theoretical guidance for fabricating PBO fibers and enhancing the interfacial bonding strength with resin matrices, thereby increasing their potential in advanced applications.Highlights Structures and properties of PBO fibers are presented. Recent advances for the surface modification of PBO fibers are reviewed. Scientific problems for improving interfacial bonding are proposed. Limitations, challenges, and development trends of PBO fibers are prospected.