Effects of silane-modified carbon nanotubes on flexural and fracture behaviors of carbon nanotube-modified epoxy/basalt composites

We investigated the effects of carbon nanotube (CNT) modification with silane on the flexural and fracture behaviors of modified carbon nanotube epoxy/basalt (CNT/epoxy/basalt) composites. Flexural and mode I fracture tests were performed using acid-treated and silane-treated CNT/epoxy/basalt composites, respectively. FT-IR analysis was conducted to determine the chemical change on the surface of basalt fiber due to the silane modification. After the fracture tests, the fracture surfaces of the CNT/epoxy/basalt composites were examined with scanning electron microscopy (SEM) to investigate the fracture mechanisms of the CNT/epoxy/basalt composites, depending on the CNT modification. The results show that the flexural modulus and strength of silane-treated CNT/epoxy/basalt composites are similar to 10% and similar to 14% greater, respectively, than those of acid-treated CNT/epoxy/basalt composites. The fracture toughness G(Ic) of silane-treated DU/epoxy/basalt composites was similar to 40% greater than that of acid-treated CNT/epoxy/basalt composites. SEM examination revealed that the improvement in the flexural and fracture properties of silane-treated CNT/epoxy/basalt composites occurred due to enhanced dispersion and interfacial interaction between the silane-modified CNTs and the epoxy. (C) 2012 Elsevier Ltd. All rights reserved.