Abstract
In this work, transmission electron microscopy (TEM) and Raman spectroscopy were used to assess the dispersion quality of carbon nanotubes (CNTs) in an epoxy matrix. Its ultimate tensile strength (UTS), engineering strain, local strain, and the elastic tensile modulus were determined experimentally. The effect of CNT sonication time in an ethanol medium was also evaluated. A statistical analysis using the t-test approach was employed to clarify how the use of CNTs affects the mechanical properties of the matrix. An increase in the UTS by 10 and 7% was observed in the cases of 0.1 wt.% single-walled carbon nanotubes (SWCNTs) and multiwalled carbon nanotubes (MWCNTs), respectively, but the elastic modulus increased significantly when using MWCNTs. A TEM analysis indicated that the dispersion quality was proportional to the content of CNTs. It is concluded that a CNT-reinforced epoxy matrix is highly sensitive to the amount of CNTs, which can explain the conflicting properties reported for such matrices in the literature.