The tensile and thermal properties of modified CNT-reinforced basalt/epoxy composites

In this study, the effect of carbon nanotube (CNT) modification on the tensile and thermal properties of CNT/basalt/epoxy composites was investigated. CNT/basalt/epoxy composites were fabricated by impregnating woven basalt fibers into epoxy resin mixed with CNTs. Three groups of composites were fabricated, consisting of unmodified, acid-modified (oxidized), and silane-modified (silanized) CNTs, each at 1wt.%. Tensile tests and dynamic mechanical analysis (DMA) were performed on each group of composites to determine the mechanical and thermal properties of the CNT/basalt/epoxy composites, depending on the surface modification of CNTs. The tensile strength and Young's modulus of silanized CNT/basalt/epoxy composites were 34 and 60% greater, respectively, than that of unmodified CNT/basalt/epoxy composites. Also the silanized composites had a higher storage modulus and T_g than unmodified and oxidized composites. The enhancement of the mechanical and thermal properties of silanized CNT/basalt/epoxy composites is attributed to improved dispersibility and strong interfacial interaction between the silane functionalized CNTs and the epoxy in the basalt fabric/epoxy composites.