Preparation of highly active aramid fiber and effect on the interface property of aramid/epoxy composites

Abstract The smooth surface and the lack of active groups make para-aramid fiber reinforced composites have poor interfacial adhesion property, which limits their applications in various fields. In this study, aramid fiber was coated with nano-coating solution and functional groups such as epoxy and amino groups were introduced to the surface of aramid fiber to enhance the surface activity of the fiber, thereby improving the adhesion between fiber and resin. The surface composition and roughness of the modified fibers were characterized by Fouier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM), respectively. The effect of functional groups on the interfacial adhesion properties of aramid/epoxy composites was studied by the interfacial shear strength (IFSS) and the flexural strength. aramid fiberter modification, the roughness and the polarity of the fiber were considerably improved. The IFSS reached 45.9 MPa with a significant enhancement by 27.5%; while the flexural strength increased from 240.7 MPa to 302.2 MPa, with a reinforcement of 25.6%, indicating that the study provides an effective method to achieve highiy active aramid fiber.