Reinforcement role of carbon nanotubes, Part I: High‐performance epoxy resin

The reinforcement role of single-walled carbon nanotubes (SWCNT) in a high-performance epoxy resin is studied in this article, with the emphasis on the deformation and load transfer mechanism. Tensile tests show that introducing carbon nanotubes (CNTs) into the epoxy resin changes the tensile strength of the material, and that the increase of Young's modulus is in good agreement with the increasing of glass transition temperature (Tg) measured by differential scanning calorimetry (DSC). Residual strains in CNTs induced during curing process have been investigated both experimentally and theoretically. Raman spectroscopy study shows that load transfers more efficiently in tension than in compression. The Raman shifts of deformed CNTs under repeated loading indirectly reveals that the load can be further transferred via friction after debonding fully occurs. Thin epoxy layers were observed on the pull out ends of CNTs, which implies the existence of the immobilized epoxy layer between CNTs and bulk epoxy. POLYM. COMPOS., 2014. © 2014 Society of Plastics Engineers