Research On The Preparation And The Properties Of Nanoparticle/Carbon Fiber-reinforced Polyimide Composites

Combination properties of carbon fiber-reinforced polymer composites arecomparable to metal alloy. Consequently, to be used in aerospace, it will not onlymeet the requirements of the high temperature and mechanical performance of thematerial, but also make the weight of spacecraft decrease. However, interfacestrength between carbon fiber and polymer affects the properties of composites. It isindicated that the mechanical properties of the composites can be improved byadding Nanoparticle into carbon fiber-reinforced polymer composites.Nanoparticle/carbon fiber (CF) reinforcement is fabricated by electophoreticdeposition (EPD), and its microstructure and morphology are characterized by SEM,FTIR, and XRD. It is proved that the no chemical bonds but physical bonds existbetween nanoparticles and CFs. Wettability and thermal performance of thecomposite reinforcement are investigated, and it is indicated that wettability ofnanoparticle/carbon fiber is better than CF, and the thermal performance is alsoprominent.The process of carbon fiber-reinforced polyimide composites (CFRP) fabrication,in which solvent immersion and thermo-compression molding are applied, is studied.We find that there are seldom pores in the composites fabricated with the secondcuring temperature system, after comparative study. The mechanical properties,fracture morphology, and TG curves are analyzed, and we find that overallperformance of the CFRP fabricated under the molding pressure of3MPa is theoptimal, when the curing temperature and time are both constant.Nanoparticle/carbon fiber/polyimide composites are fabricated based on thepreceding process, and the mechanical properties have been strengthened bynanoparticles as reinforcements. We also find that the thermostability of thecomposite gets better, by analyzing the TG curves.Thermo-oxidative aging test is taken to characterize thermo properties ofnanoparticle/CF/polyimide composites with the highest flexural strength. It is foundthat postcuring and polyimide oxidation occur during the process of thermaloxidation, which makes the flexural strength and shearing strength weaken afterstrengthening and have a better retention when the time of thermal oxidation passes1000hours. The TG rate of Nanoparticle/carbon fiber/polyimide composites arecalculated and compared with the TG rate of CFRP, and the lower TG rate provesthat the add of nanoparticles improves composite’s thermostability distinctly.