A strategy for enhancement of mechanical and electrical properties of polycarbonate/multi-walled carbon nanotube composites

Two poly(3-hexylthiophene)-g-polycaprolactones (P3HT-g-PCLs) with different degrees of polymerization (DP) of P3HT backbone were synthesized and used as a compatibilizer for bisphenol A polycarbonate (PC)/multi-walled carbon nanotube (MWCNT) composites. Both field emission-scanning electron microscopy and melt-state rheology show that MWCNTs are homogeneously dispersed in PC matrix when P3HT-g-PCL is added to PC/MWCNT composites. As a consequence, the mechanical and electrical properties of PC/MWCNT composites are dramatically improved when a small amount of P3HT-g-PCL is added to PC/MWCNT composites. It is also found that P3HT-g-PCL with lower DP of P3HT backbone is more effective to homogeneously disperse MWCNTs in PC matrix than that with higher DP of P3HT. This is because the π–π interaction between MWCNTs and P3HT-g-PCL with lower DP of P3HT is stronger than the case of P3HT with higher DP of P3HT, as evidenced by fluorescence emission spectra.