| Abstract: | A method of developing an electrical conductivity in polypropylene (PP) with a very low loading of multiwalled carbon nanotube (MWCNT) by melt‐mixing method was described. PP/high‐density polyethylene (HDPE; 70/30, w/w) was melt blended simultaneously in the presence of MWCNT using two sequential heating protocol (MWCNT was first interacted with HDPE chain at 140°C followed by melt blending of PP at 200°C). Very interestingly, a cocontinuous morphology in the blend was found even for very high asymmetric composition. This has been explained in terms of barrier effect of the MWCNT dispersed selectively in the HDPE phase that restricts the phase inversion into the matrix droplet morphology. A simple method was used for proper dispersion, distribution, and formation of effective conducting network path carbon nanotube (CNT)–CNT contact] of MWCNT through cocontinuous HDPE phase (minor phase) into PP matrix of the blend which in turn enhanced the electrical conductivity of the nanocomposite with minimum percolation threshold. The percolation threshold of PP/HDPE/MWCNT nanocomposite found at 0.352 wt% loading of MWCNT, which is significantly lower than those reported for developing electrical conductivity in PP/MWCNT nanocomposite. Phase morphology, extent of dispersion and location of the MWCNT in the blend has been investigated with a scanning and transmission electron microscopy. Thermal and mechanical properties of PP/HDPE/MWCNT nanocomposite with variation of MWCNT loading have also been studied. POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers |
