The novel characteristics of high-density polyethylene (HDPE)/calcium carbonate (CaCO3)/maleic anhydride grafted lowdensity polyethylene (LDPE-g-MA) composites were examined in relation to the reaction temperature and the amount of LDPE-g-MA for melt mixing conditions. HDPE/CaCO3/LDPE-g-MA composites were prepared by melt mixing. The tensile strength of the composites decreased with increase in CaCO3, but thermogravimetric analysis (TGA) revealed that the composites had higher thermal stability than pure HDPE. Differential scanning calorimetry (DSC) analysis showed that the crystallinity (Xc) and crystallization entropy (ΔSc) of the composites decreased with increase in temperature and the amount of LDPE-g-MA. These results were consistent with the activation energy (Ea) derived from the Kissinger method. This study demonstrates that the composites were influenced by the temperature and the amount of LDPE-g-MA. In addition, a certain amount of CaCO3 is expected to act as a stable nucleating agent, which thus accelerates the crystallization rate.

Keywords: Hybrid composites, Polymer-matrix composites (PMCs), Thermomechanical properties