Morphology-dependent performance of Mg3Al–CO3 layered double hydroxide as a nanofiller for polypropylene nanocomposites

Abstract

In this contribution, the morphology-dependent performance of Mg₃Al–CO₃ layered double hydroxide (LDH) as a nanofiller for polypropylene (PP) was evaluated for the first time. Three types of PP nanocomposites with 0-dimensional spherical, 2-dimensional plate-like, and 3-dimensional flower-like Mg₃Al–CO₃ LDHs as nanofillers were prepared using a solvent mixing method. The influence of morphology as well as the loading of LDHs on the thermal stability, flame retardancy, and rheological behaviors of the PP/LDH nanocomposites was then systematically investigated. The results showed that the thermal stability was significantly improved after incorporating LDH nanoparticles. For instance, the T_0.5 of the 13.0 wt% PP/plate-like LDH nanocomposite was increased by 61 °C compared to that of pure PP. The addition of Mg₃Al–CO₃ LDHs can enhance the flame retardant performance of PP as well, and the efficiency was dependent on both the morphology and loading of LDH. The influence on the storage modulus (G′) and loss modulus (G′′) of PP was observed to follow the order of spherical > plate-like > flower-like. This work demonstrated that more attention should be paid to the influence of LDH morphology for the future design of the polymer/LDH nanocomposites.