Basalt fibers (BF) are often used as reinforcement of composite materials owing to their high strength, heat resistance, and corrosion resistance. The surface‐interface interaction between the fibers and the matrix material plays a key role in determining the mechanical properties of the composite. In this work, BF‐polycarbonate (PC) composites were prepared using melt blending and extrusion molding. BF was modified with 3‐aminopropyltriethoxysilane (KH550) to enhance surface roughness and improve interfacial bonding, resulting in modified fibers (KBF). The bending strength of KBF‐PC was increased 28.8% compared with unmodified BF‐PC. Further modification of BF using polyethylene glycol (PEG) and KH550 to obtain PKBF, resulting in a 42.26% increase in bending strength. To further enhance the mechanical properties of the composites, PKBF was modified with nano‐alumina, resulting in a 48.41% increase in bending strength. The relationship between fiber content and composite mechanical properties was studied using theoretical models such as Halpin‐Tsai, Kelly‐Tyson, and ROM. The mechanisms by which different modified fibers enhance the mechanical strength of composites were explored. The interfacial compatibility between the matrix material and BF would be significantly improved through surface modification, resulting in enhanced mechanical performance of the composite.Highlights
PEG‐KH550 treatment of basalt fibers to enhance interfacial adhesion.
Al2O3 modified basalt fibers to enhance the bending strength of the composite.
Treated fibers exhibit improved tensile and bending properties of composite.
The mathematical model shows the reliability of the experimental data.