Performance Of The Interfacial Propertites Of Carbon Nano-tube/pamam/carbon Fiber Composite

Polymer composite reinforced by carbon fiber(CF) has been extensively used in many fields such as aerospace industry, automotive industry, steamship industry,petroleum industry,chemical industry. HoweVer, the applications of carbon-fiber reinforced composites are limited because of the poor interfacial performence caused by carbon-fiber's small active specific surface area, low surface energy and lipophobic surface between matrix material and reinforcement. The exceptionally high specific stiffness and strength of carbon nanotubes (CNTs) and their fiber-like structure have stimulated extensive investigations on the mechanical properties of polymer composites reinforced with CNTs.In view of the interfacial performance improvement between carbon fiber and the resin system, carbon fiber is modified by poly (amido amine)——of a dendrimer and nanotubes, and we call the carbon fiber modified by poly (amido amine) and nanotubes carbon nanotube/PAMAM/carbon fiber reinforcement (of a novel reinforcement).we investigate the surface properties of the novel reinforcement and its composite interfacial properties. The matrix material under investigation is E-51. And the preparation of carbon nanotube/PAMAM/carbon fiber has three processes: carbon nanotube modification, carbon fiber modification and preparation of new reinforcement in turn. Finally, carbon nanotubes with acid treatment are grafted onto the surface of carbon fiber modified by PAMAM with amido bond (-NH-CO-), which can be proved by XPS and IR. Furthermore, the SEM and AFM images of CNTs/PAMAM/CF also prove that nanotubes are grafted to carbon fiber surface by different ways. The result of contact angle implies that, compare with the raw carbon fiber, the CNTs/PAMAM/CF surface energy increases by 28.4%, which shows that the latter interfacial shear strength(IFSS) value of composite is higher. In our work, critical fiber length method and microbonding method are used to calculate the interfacial shear strength of composite. The results of two methods are similar that the IFSS of composite reinforced by CNTs/CF MSR increases about 210%.