Nanofiber–sheathed structure for enhancing interfacial properties of basalt fiber-reinforced composites

Basalt fibers (BFs)-reinforced composites exhibit inadequate interfacial properties because of its chemically inert surface. In this paper, we applied the electrospinning method to prepare polyacrylonitrile (PAN) nanofiber-sheathed BFs (SBFs). The SBFs were further used to synthesize novel BFs-reinforced epoxy composites with enhanced interfacial properties. A fiber pull-out test was used to assess the interfacial shear strength (IFSS) of the composites. The results showed a 31.33% increase in the IFSS of the BFs composites after introducing the PAN nanofiber-sheathed structure at the optimal electrospinning parameters. The improvement originates mainly from the formation of a gradient interfacial layer between the BFs and the epoxy matrix. The gradient interfacial layer enables uniform stress transfer from epoxy to BFs and promotes interfacial adhesion. The method used in this work is suitable for a cost-efficient, continuous large-scale production using a straightforward preparation process.