Enhancing the mechanical properties of basalt fiber/nylon 6 composites by surface roughening and hydrogen bonding interaction

Abstract Inspired by the strong adhesion of mussels, basalt fibers (BFs) were modified with polydopamine and then composited with nylon 6. The effect of polydopamine content on the interfacial interactions and mechanical properties of the composites was investigated. In addition, silica nanoparticles were grown on the surface of polydopamine‐modified BFs to investigate the synergistic effect. The study revealed that the mechanical properties of the composites based on polydopamine‐modified BF were gradually enhanced with the increase of the dopamine coverage concentration, and gradually decreased after reaching the peak. 0.5 g/L concentration of dopamine solution modified BFs showed the best enhancement effect on nylon 6, and its tensile strength could reach 133.1 MPa, which was 28.5% higher than that of the unmodified composites. The tensile strength of the composites modified with both dopamine and silica nanoparticles reached 157 MPa, which was 51.7% higher than that of the unmodified composites. In addition, scanning electron microscope images of fracture sections confirmed the strong interfacial interaction between BF and PA6. Highlights The surface roughness of BF was increased by nano‐SiO 2 . Hydrogen bonding was formed between PDA and PA6. Physical interlock was formed between nano‐SiO 2 and PA6. Tensile strength increased by 51.7% with both nano‐SiO 2 and PDA. Stronger interfacial interaction leads to higher thermal stability.