Polydopamine-coupling of carbon nanotubes onto microscaled basalt fiber to enhancing mechanical, thermal and tribological properties of composite materials

Under mild and green conditions, carbon nanotubes (CNT) were grafted onto the surface of basalt fiber (BF) via polydopamine (PDA) as coupling agent in an attempt to improve mechanical, thermal and tribological properties of BF composites. It showed CNT were coated uniformly and formed a thick flocculent cladding layer on the surface of BF. With improved interfacial interaction supported by chemical coupling and mechanical meshing between BF and matrix, impact strength, flexural strength and flexural modulus of the CNT grafting BF (CNT-PDA-BF) composites increased by 28%, 23% and 24%, respectively. Besides, thermal conductivity of the CNT-PDA-BF composites increased by 24% and thermal stability also improved. Furthermore, cracks on the worn surface of CNT-PDABF composites almost disappeared, wear debris became smaller and roughness significantly decreased, thus wear resistance of the BF composites improved 36%. Therefore, it provided a novel and effective surface modification method for improving comprehensive performance of BF composites.