ABSTRACT A blend of high‐density polyethylene (HDPE) and linear low‐density polyethylene (LLDPE) was incorporated with different content of graphene nanoplatelets (GNP) and aluminum hydroxide (ATH) together reinforced with montmorillonite (MMT) and prepared through melt compounding. The influence of the GNP loading (2, 3, 4 phr) and ATH (10, 15, 20 wt%) filler content on the mechanical, thermal, flame retardancy, morphological, and rheological properties were studied and reported. For mechanical properties, a slight decrease in tensile strength was observed for all HDPE/LLDPE nanocomposite samples compared to the neat HDPE/LLDPE blend. However, a drastic drop in elongation at break was found for all HDPE/LLDPE nanocomposites compared to the neat HDPE/LLDPE blend sample; while the Young's modulus of those samples with higher GNP and ATH filler content was increased considerably compared to the neat HDPE/LLDPE sample. The thermogravimetric analysis (TGA) results have shown that the initial decomposition onset temperature was decreased for HDPE/LLDPE nanocomposite samples containing GNP and ATH compared to the neat HDPE/LLDPE sample. However, the maximum decomposition temperature increase was observed for all HDPE/LLDPE nanocomposite samples containing higher GNP and ATH filler loading together with MMT nanoclay. Furthermore, the differential scanning calorimetry (DSC) results have shown no significant changes in melting and crystallization temperatures for HDPE/LLDPE nanocomposite samples containing ATH and GNP compared to the neat HDPE/LLDPE blend. However, a decrease in percent crystallinity was observed for HDPE/LLDPE nanocomposite samples compared to the neat blend. Both the flammability test, UL‐94, and scanning electron microscope (SEM) results have revealed that the flame retardancy properties of neat HDPE/LLDPE blend have enhanced considerably due to the higher GNP and ATH filler content loading together with MMT nanoclay into the neat blend matrix. All rheological properties have shown a similar pattern of increase, at the lower frequency region, with increasing GNP and ATH filler loading content. X‐ray diffraction (XRD) results have shown the decreased 2‐theta and increased interlayer d spacing slightly for samples containing GNP and ATH fillers, which could be due to intercalated polymer nanocomposite.
Yussuf et al. (Sun,) studied this question.