Reinforcing effect of surface‐modified multiwalled carbon nanotubes on flexural response of E‐glass/epoxy isogrid‐stiffened composite panels

The lack of scientific information about the utilization of nanoparticles on grid-stiffened composite (GSC) fabrication was the driving force for the selection of this study. In the present work, GSC panels reinforced with various amounts of surface modified multi-walled carbon nanotubes (MWCNTs) (0–0.5 wt% at a step of 0.1 wt%) have been investigated in terms of their capability to improve the mechanical properties under three-point flexural condition. Out of these specimens, the maximum value of improvement in the flexural stiffness, load bearing capacity, and specific energy absorption was related to the specimen with 0.4 wt% MWCNTs. It would be worth mentioning that in these structures, a considerable energy absorption was observed after the primary failure related to the load peak. The field-emission scanning electron microscopy observations of the fracture surfaces of the nanocomposites clearly indicated that the enhancement in the flexural properties was due to the improvement in the interfacial adhesion between the E-glass fibers and MWCNTs-enhanced epoxy matrix.