Effect of the Core/Shell-Structured Meta-Aramid/Epoxy Nanofiber on the Mechanical and Thermal Properties in Epoxy Adhesive Composites by Electrospinning

Aramid fibers have been widely used in fiber-reinforced composites due to their low coefficient of the thermal expansion (CTE) and high fracture toughness. However, aramid composites have poor adhesion characteristics between the fibers and the resin because the aramid fibers are chemically inert and contain insufficient functional groups. In this work, a core/shell structure of meta-aramid/epoxy nanofibers with polymer blends was prepared using electrospinning to enhance the interface adhesion of the composites. The core/shell structure of the meta-aramid/epoxy nanofibers was characterized by field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR) were conducted on the nanofibers to study their chemical composition. The single-lap-joint test was performed to evaluate the adhesion strength of the metal-to-metal adhesive joint using the meta-aramid nanofiber-reinforced adhesive. An improvement in the adhesion strength of the reinforced epoxy adhesive used to generate meta-aramid/epoxy nanofibers was achieved through in-situ nanointerface core/shell structure formation by electrospinning.