Effect of compounding sequence on localization of carbon nanotubes and electrical properties of ternary nanocomposites

Multiwalled carbon nanotubes (MWNTs) were incorporated into polyamide 12 (PA12) and PA12/polyethylene-octene elastomer grafted with maleic anhydride (POE-g-MA) components by melt compounding. The addition of MWNTs improves electrical, dynamic mechanical and thermal properties of PA12. In the presence of 20 wt.% POE-g-MA, PA12/POE-g-MA/MWNT ternary nanocomposites exhibit substantially improved electrical conductivities as compared to PA12/MWNT binary nanocomposites with the same loading of MWNTs. The electrical conductivity shows 5–6 orders of magnitude increase in the percolation threshold region due to the volume exclusion effect of POE-g-MA. Variation of the compo unding sequence of the three components results in large difference in electrical conductivity of the ternary nanocomposites at the low loading of 2 wt.% MWNTs, while the difference becomes slight at high MWNT loading of 4 wt.%.