Comparative study of carbon-based nanofillers for improving the properties of HDPE for potential applications in food tray packaging

High-density polyethylene (HDPE)/carbon filler composites for potential applications in food tray packaging were prepared by melt compounding HDPE with one-dimensional (1D)-multiwalled carbon nanotubes (MWCNT), two-dimensional (2D)-graphene oxide (GO) and three-dimensional (3D)-carbon black (CB) on a twin-screw extruder. The morphology of fillers inside the HDPE matrix was characterized and correlated to the mechanical, thermal and barrier properties of the nanocomposites. The results showed the distinct effect of CB on the mechanical, thermal and barrier properties of HDPE from MWCNT and GO. The morphological analysis revealed uniform dispersion for all the fillers, but the agglomerate formation was a lot more evident in MWCNT-based nanocomposites. Ball milling solved the large agglomerate formation for MWCNT and produced nanocomposites with improved mechanical properties. In comparison to 1D and 2D nanofillers, the 3D-CB filler showed remarkable contribution to tensile toughness but caused a reduction in barrier properties of HDPE, the increase in tensile toughness was attributed to uniform dispersion of the filler, enhanced mechanical interlocking between filler and polymer, appearance of high degree of crazing on tested samples and increase in nanocomposite internal temperature during tensile testing.