Analysis of mechanical and thermal properties of epoxy multiwalled carbon nanocomposites

Abstract

The main objective of this study was to investigate the efficiency of the sonication process and of multi-walled carbon nanotubes (MWCNTs) content on the mechanical and thermal properties of an epoxy matrix. Three different sonication powers (25, 50 and 75 W) were used to disperse the MWCNTs (0.2%, 0.4% and 0.6% wt.) in the epoxy matrix. Tensile tests were performed to determine the mechanical properties of the nanocomposites, while the thermal properties were determined by the thermogravimetric analysis (TGA) and the Differential Exploratory Calorimetry (DSC). Finally, a SEM analysis was used to investigate the morphology of the tensile fractured surface and the dispersion of the nanotubes in the polymeric matrix, since the quality of dispersion influences the mechanical and thermal properties of nanocomposites. It was found that the addition of carbon nanotubes to the epoxy matrix and the parameters of the sonication process affect the mechanical and thermal properties of nanocomposites. An increase of approx. 14% in tensile strength and 15% of Young’s modulus, when compared to the pure epoxy matrix was found for 75 W sonication power output and 0.6% MWCNTs weight percentage. The thermal analysis indicated that the presence of MWCNTs increased the Tonset of the nanocomposites when compared to pure epoxy resin. Finally, increasing the sonication power output leads to higher Tg of the nanocomposites studied here.