Surface Modification Of PBO Fiber Via Low-temperature Plasma

Poly (p-phenylene-2 ,6-benzobisoxazole), referred to PBO, PBO fiber is a liquid crystal polymer technology system in the spinning of high-performance fiber. In strength, the modulus, heat resistance and flame-retardant properties of the special, it is widely used. But with its smooth surface, surface activity was very low and the chemical inertia, and resin-based interface bonding of the poor, it severely restricted the high-performance composite materials in the application.So the PBO fiber was under surface modification, increasing fiber surface polarity, the key technology breakthroughs will enable the PBO fiber reinforced composite materials development is of great significance, and for the aerospace, aviation and defense fields, such as high-tech composite materials Upgrading of a catalytic role. With the traditional chemical and physical modification methods, compared to at normal temperature and pressure plasma processing method because of the fiber surface reaction easy to control, the smaller body injury, the extreme inertia of the surface of the polymer significantly modified effect, but also suitable for Continuous production, with online matching.This paper studies on a regular PBO fiber RF atmospheric temperature plasma surface treatment after the interface with epoxy glue and shear strength of the changes, research shows that:(1) low-temperature plasma surface treatment PBO fibers on the surface the introduction of the polar groups, the surface elements have greatly improved, the plasma etching the surface fibers, epoxy resin and bonding, the mechanical lock. Interfacial shear strength increased 50-80 percent; loss of a small fiber strength.(2) PBO fiber by the low-temperature plasma treatment, the increasing influence of the interface shear, ILSS increase; (3) after SEM observation, low-temperature plasma surface treatment PBO fiber damage occurred in the first fiber surface, a shear failure;(4) processing time not too long, or too long on easy for the fiber of over-etching;(5) may be appropriate to add surface coupling, the response to further control and improve results;(6) the plasma after the invasion of fiber be greatly improved, invasion angle decreases. Unprocessed fiber contact angle greater than 100 degrees, argon and argon gas mixture of oxygen after the fiber into contact angle of 86 and 67.3. Note RF plasma at normal temperature and pressure of PBO fiber surface to increase the role of the fiber surface roughness, the contact angle decreases.(7) from infrared analysis showed that: the fiber surface plasma treatment because of the final remnants of the role of free radicals, and in the air after contact with the surface of materials hydrophilic group, hydroxyl content improved greatly improve the wetting, when its And composite resin, the interface bonding of the two has improved, single-fiber pull out the strength to raise.