Preparation of polystyrene - multi walled carbon nanotube nanocomposite with improved mechanical properties using response surface methodology

In this research, with the aim of improving mechanical properties of polystyrene (PS), multi walled carbon nanotube (MWCNT) was selected as reinforcement agent. PS-MWCNT nanocomposite was prepared by mixing of MWCNT nanostructurs with a solution of PS. The effects of three factors containing MWCNT percentage, film drying temperature and stirring time were investigated in different levels by Box Behnken design of response surface methodology (RSM). According this method, 15 experiments were performed. The tensile strength values of nanocomposite films were used as response for data analyzing by variance analysis. The linearity of normal probability plot of the residuals established the correctness of the proposed model. The contour and surface plots of RSM were studied and the optimal conditions of nanocomposit preparation were determined. The results showed that increasing of MWCNT percentage and stirring time cause to increase of tensile strength, while the increasing of film drying temperature causes to decrease of tensile strength. Also, some physicochemical properties of the nanocomposite film were examined using FT-IR spectroscopy and TGA techniques.