Mechanical and viscoelastic properties of epoxy nanocomposites reinforced with carbon nanotubes, nanoclay, and binary nanoparticles

Mechanical and viscoelastic properties of polymer nanocomposites reinforced with carboxyl functionalized multiwalled carbon nanotubes (COOH-MWCNT), montmorillonite nanoclays (MMT), and MWCNT/MMT binary nanoparticle were investigated. In this study, 0.3wt% of COOH-MWCNT, 2wt% of MMT, and 0.1wt% COOH-MWCNT/2wt% MMT binary nanoparticles by weight of epoxy were incorporated to modify SC-15 epoxy resin system. Nanocomposites were subjected to flexural test, dynamic mechanical, and thermomechanical analyses. Morphological study was conducted with microscopy. Addition of each of the nanoparticles in epoxy showed significant improvement in the mechanical and viscoelastic properties compared to those of the control ones. However, best results were obtained by addition of 0.1% MWCNT/2% MMT binary nanoparticles in epoxy. Nanocomposites modified with binary nanoparticles exhibited about 20% increase in storage modulus as well as 25? increase in the glass transition temperature. Flexural modulus for binary nanoparticle modified composites depicted about 30% improvement compared to the control ones. Thus, improvement of mechanical and viscoelastic properties was achieved by incorporating binary nanoparticles to epoxy nanocomposites. The increase in properties was attributed to the synergistic effect of MWCNTs and nanoclay in chemically interacting with each other and epoxy resin as well as in arresting and delaying the crack growth, once initiated.