Mechanically robust, corrosion and impact resistance polyimide nanofiber/epoxy composite by mechanochemical fabrication

This study aimed to explore the application of a mechanochemical method for effectively integrating polyimide nanofibers, which are widely recognized for their outstanding thermal and mechanical properties, into an epoxy resin matrix. The researchers observed an 87.5% reduction in the diameter of polyimide nanofibers after mechanical treatment. The dispersion, compatibility, and interface between the nanofibers and epoxy matrix were analyzed using molecular dynamics simulations and scanning electron microscopy. The addition of polyimide nanofibers significantly increased the binding energy of the composite, resulting in a 52.8% improvement. Moreover, compared to pure epoxy resin, the inclusion of modified polyimide nanofibers led to a 21.9% increase in tensile strength and an 18.8% increase in impact strength. The PI/epoxy composite also exhibited a 15.6% increase in tensile strength and a 16.4% increase in impact strength. Additionally, electrochemical corrosion analysis showed that the PI/epoxy composite had excellent corrosion resistance. In conclusion, due to the exceptional mechanical properties and strong interfacial adhesion of polyimide nanofibers, the PI/epoxy resin composite demonstrated significant overall performance improvement compared to pure epoxy resin.