Effects of MWCNT and nickel-coated carbon fiber on the electrical and morphological properties of polypropylene and polyamide 6 blends

In this study, the effects of hybrid fillers such as multi-walled carbon nanotube (MWCNT) and nickelcoated carbon fiber (NCCF) on the electrical conductivity of polypropylene (PP) and polyamide 6 (PA6) blends were investigated. Polypropylene- g -maleic anhydride (PP- g -MAH) was used as a compatibilizer of the PP/PA6 blends. From the results of the transmission electron micrographs of the PP/PA6 (70/30)/MWCNT composites, the MWCNT preferred to locate more in the PA6 phase than in the PP phase. This was possibly due to the lower interfacial tension of the PA6/MWCNT composite compared to that of the PP/MWCNT composite. For the PP/PA6 (70/30)/NCCF/MWCNT (3 phr) hybrid filler composites, values of the electrical conductivities were increased with the increase of the NCCF content. The increase in electrical conductivity was possibly due to the increased electrical pathway with the addition of NCCF content. From the results of the electrical conductivity and morphology of the PP/PA6/NCCF/MWCNT composites, it is suggested that selective localization of the MWCNT in the PA6 phase affected the increased electrical conductivity of the PP/PA6/NCCF/MWCNT composites. The hybrid fillers NCCF and MWCNT could produce a synergistic effect on the electrical conductivity, and the electromagnetic interference shielding efficiency (EMI SE) of the PP/PA6 (70/30)/NCCF/MWCNT composites.