STUDYING PHYSICAL AND MECHANICAL PROPERTIES OF EPOXY/CNTS NANOCOMPOSITES

Abstract

Epoxy/cnts nanocomposites were prepared using pristine and functionalized multiwalled carbon nanotubes (p-MWCNTs and f-MWCNTs). The functionalization of MWCNTs was done by COOH groups and FT-IR analysis was performed to confirm successful attachment of COOH groups to MWCNTs. The different concentrations of Epoxy/CNTs nanocomposites were prepared by solution mixing and resin casting method. A comparison study was carried out between both types of nanocomposites to investigate the change in morphology, mechanical, thermal, thermo-mechanical and dielectric properties. Structure and morphology of the epoxy/cnts nanocomposites were studied using sem. SEM images revealed better dispersion of f-MWCNTs than p- MWCNTs into the epoxy matrix with nanofillers threshold concentration at 0.5%wt. ratio and at higher wt% the CNTs were agglomerated in the epoxy matrix. Good and uniform dispersion of nanofillers lead to polymer chain wrapping/adherence which in turn enhanced the tensile strength and modulus of epoxy/f-MWCNTs as compared to epoxy/p-MWCNTs. The mechanical properties were improved at the expense of strain at break and maximum increase in modulus was 21% and 64% whereas enhancement in tensile strength was 100% and 105% for epoxy/p-MWCNTs and epoxy/f-MWCNTs nanocomposites, respectively. The glass transition temperature (Tg) was measured by DMA and it was decreased by increasing the wt% of MWCNTs and the effect of decrease in Tg was higher in case of f-MWCNTs. The thermal stability was determined by TGA and it was also decreased by increasing the wt% of MWCNTs, the effect of decrease was higher in p-MWCNTs. Moreover, impedance analysis confirmed that dielectric properties and ac conductivity were improved by addition of MWCNTs into epoxy matrix.