Effect of compatibilization on electromagnetic interference shielding performance of carbon nanotube based blend nanocomposites

The blend nanocomposites of multiwalled carbon nanotube (MWCNT) with polycarbonate/ polypropylene (PC/PP) blends have been made by melt mixing technique. The effect of polypropylene-grafted maleic anhydride (PP-g-MA) as a compatibilizer has played a pivotal role in reducing the interfacial tension and thereby enhancing the attenuation performance of blends. High resolution transmission electron microscope (HRTEM) was used to study the filler dispersion and network connections of its microstructure. PP-g-MA reduces the interfacial tension between the blend components thus stabilizing the dispersion against coalescence. Electrical percolation was shown at 1wt.% CNT content for Blend/PP-g-MA/MWCNT nanocomposites. All nanocomposites exhibited an increase in the permittivity with the increase in MWCNT loading which could be attributed to the interfacial polarization effects. There was also a remarkable 2.5 fold increase in total shielding effectiveness (54.78dB) of compatibilized blends when compared to uncompatibilized (22 dB). (author)