High performance linear low density polyethylene nanocomposites reinforced by two-dimensional layered nanomaterials

Two-dimensional (2D) layered nanomaterials, including pristine α-zirconium phosphates (ZrP), amine-intercalated organophilic α-zirconium phosphates (OZrP) and organophilic montmorillonite (OMMT), are directly incorporated into linear low density polyethylene (LLDPE) by injection molding. ZrP and OZrP achieve good dispersion in the LLDPE matrices while OMMT forms agglomerations as observed by scanning electron microscope (SEM). The differential scanning calorimetry (DSC) analysis reveals that well-dispersed ZrP and OZrP could act as a nucleating agent to increase crystallinity of LLDPE while the agglomerated OMMT decreases the crystallinity of the polymer matrix. Tensile tests show that the strength and ductility of the LLDPE/ZrP nanocomposites can be enhanced simultaneously, due to the high modulus and parallel alignment along the injection direction for ZrP in matrix. The heat resistance of LLDPE, can also be enhanced by the addition of 2D nanoplatelets, among which ZrP perform the best, showing an increase of ∼16 °C in heat distortion temperature.