Poly(butylene succinate)/high density polyethylene blend-based nanocomposites with enhanced physical properties – Selectively localized carbon nanotube in pseudo-double percolated structure

Abstract

In this study, immiscible poly(butylene succinate)/high density polyethylene (PBS/HDPE) blend-based nanocomposites were successfully prepared through a melt mixing process. Carbon nanotube (CNT) and maleated HDPE (PEgMA) served as the reinforcing nanofiller and compatibilizer, respectively. Scanning electron microscopy images showed that PEgMA played an efficient compatibilizer role for reducing the dispersed domain size of HDPE in the PBS/HDPE blend. The added CNT was mainly selectively localized in the HDPE domains, leading to a pseudo-double percolated structure. Thermogravimetric analysis revealed that the presence of CNT evidently enhanced the thermal stability of HDPE phase in the composites. Differential scanning calorimetry results showed the nucleation effect of CNT on HDPE crystallization, whereas PEgMA accelerated the crystallization of PBS. The rigidity of neat PBS increased after blending with HDPE and then further increased after the formation of nanocomposites. The Young's modulus increased up to 50% compared with neat PBS in the 3 phr CNT-added composite. Measurement of the rheological properties confirmed the achievement of pseudo-network structure in the compatibilized blend and composites. The electrical resistivity of the blend drastically reduced, by up to 8 orders, when 3 phr CNT was added into the blend. The electrical percolation was constructed at a CNT loading of 0.6–1 phr.