3D printing of ABS Nanocomposites. Comparison of processing and effects of multi-wall and single-wall carbon nanotubes on thermal, mechanical and electrical properties

The following paper reports on a comparative study of the effects of two types of carbon nanotubes, namely multiwall (MWCNT) and single-wall (SWCNT) carbon nanotube, on the properties of 3D-printed parts produced with acrylonitrile-butadiene-styrene (ABS) nanocomposites with various CNT loadings of 5-10 wt.%. Quasi-static tensile properties and Vicat softening temperature of 3D-printed parts were enhanced with the increasing CNT content. The highest enhancement in tensile properties was observed for the ABS/CNT nanocomposites at 10 wt.% filler loading. 3D-printed ABS/SWCNT composites showed higher tensile modulus, better creep stability and higher Vicat temperature. However, the strength of ABS/SWCNT 3D samples is relatively lower than that of ABS/MWCNT. In addition, 3D-printed parts exhibited anisotropic electrical conductive behaviour, which has a conductivity of through-layer of about 2-3 orders of magnitude higher than cross-layer. The highest conductivity of 3D-printed samples reached 25.2 S/m, and 9.3 S/m for ABS/MWCNT and ABS/SWCNT composites at 10 wt.%, respectively. The results obtained, i.e. the successful fuse filament fabrication and the consequent electromechanical properties, confirm that these 3D printable nanocomposite could be properly utilized for the production, and application up to about 90°C, of thermoelectric devices and/or resistors for flexible circuits