A facile method to prepare multifunctional PBO fibers: Simultaneously enhanced interfacial properties and UV resistance

A new method combining surface coating with chemical grafting to prepare poly(p-phenylene benzobisoxazole) fiber-silica-graphene oxide (PBO-SiO ₂-GO) hybrid fiber was proposed. The chemical composition, surface morphology, surface roughness (R_a), surface energy, interfacial shear strength (IFSS), single filament tensile strength (TS) and ultraviolet (UV) resistance of PBO fibers before and after modification were investigated. Experimental results revealed that the PBO fiber surface was covered by a silica coating, onto which GO was successfully grafted through chemical bonds. The R_a and surface energy of PBO-SiO₂-GO were obviously increased in comparison with that of an untreated one. The IFSS of its composites was greatly improved due to the excellent wettability and mechanical interlocking of GO. Meanwhile, TS had no obvious decrease after the surface coating and grafting process. Moreover, the introduction of silica coating on the fiber surface led to a better UV resistance than that of an untreated one. We believe this effective method may provide a novel surface modification strategy for developing multifunctional fibers.