Investigation of the Effects of Multi-Wall and Single-Wall Carbon Nanotubes Concentration on the Properties of ABS Nanocomposites

The effects of two types of carbon nanotubes, namely multiwall (MWCNT) and single-wall (SWCNT) carbon nanotube, on the thermal and mechanical properties of acrylonitrile-butadiene-styrene (ABS) nanocomposites, have been investigated. ABS filled-CNT nanocomposites with various filler loadings of 5-10 wt% were properly produced by a solvent-free process in blend compounding at 190 degrees C. Compression moulded plates and extruded filaments were obtained at 190 degrees C and 230 degrees C, respectively. Melt flow index (MFI), shore hardness, Vicat temperature, differential scanning calorimeter (DSC) and thermogravimetric analysis (TGA) were performed to characterize and compared the different CNT nanocomposites. ABS/SWCNT composite filaments showed higher tensile properties (i.e., stiffness and strength), than ABS/MWCNT. The electrical resistivity of ABS/SWCNT and ABS/MWCNT filaments decreased to 0.19 omega.cm and 0.65 omega.cm for nanocomposites with 10 wt% of nanofillers; a power law was presented to describe the electrical resistivity of composites as a function of the CNTs content. A final comparative parameter regarding melt flow, stiffness and conductivity was also evaluated for understanding the combined effects of the nanofillers. SWCNT nanocomposites exhibited better overall cumulative results than MWCNT nanocomposites.