Characterization of carbon nanotube- and organoclay-filled polypropylene/poly(butylene succinate) blend-based nanocomposites with enhanced rigidity and electrical conductivity

Abstract

In this study, immiscible polypropylene/poly(butylene succinate) (PP/PBS) blend-based nanocomposites were successfully prepared using an internal mixer. Carbon nanotube (CNT)/organo-montmorillonite (15A) and maleated PP (PPgMA) served as the reinforcing nanofillers and compatibilizer, respectively. Scanning electron microscopy results showed that PPgMA played an efficient role as compatibilizer for reducing the dispersed domain size of PBS in the blend. The added CNT was randomly distributed within the PP and PBS phases, whereas 15A was selectively located in the PBS domain. Differential scanning calorimetry results confirmed the nucleation effect of CNT on the PP/PBS crystallization, but 15A addition only facilitated the PBS crystallization. Thermogravimetric analysis revealed that CNT and 15A both enhanced the thermal stability of the blend under air environment. The rheological property measurements confirmed the significant change in microstructure of composites through developing the pseudo-network structure with CNT and/or 15A additions. The Young’s modulus (YM) of PP/PBS blend increased evidently with the inclusion of CNT. The incorporation of 2.5 phr CNT evidently increased the YM by approximately 243% compared with that of neat PBS. The electrical resistivity of the samples drastically reduced with the addition of CNT up to 10 orders of drop at a 3-phr CNT loading. The electrical percolation was constructed at a CNT content of 0.5 phr.