Effect of modified MWNTs on electrical and thermal conductivity of epoxy-MWNTs nanocomposites

Application of polymeric materials in some applications is inhibited due to their low thermal conductivity. In this study epoxy nanocomposites of three differently modified carbon nanotubes were prepared and their thermal, electrical and mechanical properties were investigated. Multiwall carbon nanotubes due to their high thermal conductivity and low price are one of the best options to improve thermal properties of polymers and make highly conductive polymeric composites. Acidic oxidation, amine grafting and Fridel-Craft reaction were employed to prepare modified carbon nanotubes; then resulting nanotubes were sonicated with epoxy resin. During mixing process epoxy groups react with grafted functional groups (such as amine groups) and a good dispersion is obtained. It was found that nanocomposites obtained by Fridel-Craft acylaion reaction have superior thermal and electrical conductivity compared to those prepared with acid oxidation and also a rigid intermediate between nanotube and matrices cause to better conductivity. Therefore addition of a very low amount of benzene tri carboxylic acid (BTC) modified nanotubes can result in a considerable improvement in thermal and electrical conductivity of resulting composite.