The effect of interfacial properties of PBO fiber surface modified by oxygen plasma on quasi-static and dynamic mechanical properties of monofilament composites

PBO(p-phenylene benzobisoxazole) fibers have great application potentials in various engineering fields while the excessively smooth surface hinders their property to a large extent. In present work, the surface of PBO fiber was modified by oxygen plasma treatment with different power and time, and the epoxy resin composite before and after PBO fiber modification was prepared. The results show that the O/C ratio increases with the introduction of carboxyl group on the surface of PBO fiber. With the increase of plasma treatment power and time, the surface roughness of the fiber surface increases first and then decreases. When the treatment time of 5minutes under 150W, the IFSS increases from 21.01MPa to 56.60MPa, reaching the optimum property. After modification, the maximum strength of monofilament fiber decreases slightly under quasi-static and dynamic conditions. The results in present work can provide reference for the subsequent structural design of overall composite materials.