Crystallization, melting, and mechanical behavior of calcium carbonate‐based nanocomposites of crosslinked high density polyethylene

In this work, novel nanocomposites of silane crosslinked high density polyethylene (PEX) and nano‐sized calcium carbonate (NCC) were prepared using a lab‐scale corotating twin screw extruder. Thermal analysis, which was carried out through differential scanning calorimetry demonstrates reduction of crystallinity index and specific heat capacity of PEX by adding NCC content, while an ascending trend was observed for crystallization rate and no important change was found for growth dimension of the crystalline lamellaes. The results of mechanical analysis show enhancement of tensile modulus compared to neat PEX by adding 10 wt% of NCCs which is attributed to good matrix/filler adhesion. On the other hand, yield tensile strength showed inverse trend while elongation at break increased gradually by adding filler up to 5 wt% NCCs and then decreased at higher filler contents due to agglomeration of NCC particles. The Counto model was used to predict the tensile modulus of nanocomposites, successfully. POLYM. COMPOS., 38:E402–E411, 2017. © 2016 Society of Plastics Engineers