Agglomerative Suppression and Synergistic Reinforcement of Hybrid GO-hBN/Polymer Nanocomposites with High Filler Contents

Mimicking the structure of nacres with high filler contents and layered structures has been demonstrated to be a promising strategy to improve the mechanical properties of nanocomposites. However, in the fabrication of such nanocomposites, the incorporation of fillers at high contents often suffers from their agglomeration that remarkably limits their mechanical performances, which is difficult to avoid and evaluate. In this work, nanocomposites, mimicking the structure of nacres, have been prepared using high content graphene oxide (GO) and hexagonal boron nitride (hBN) hybrid fillers, where the incorporation of hBN suppresses the agglomeration of GO. This leads to superior mechanical properties of the hybrid nanocomposites than those reinforced with a single type of fillers, especially at high filler contents. Based on the three-phase rule of mixtures, a concept of ‘dispersion factor’ is proposed. A higher dispersion factor of GO is found in the hybrid nanocomposites than in the nanocomposites reinforced with just GO, demonstrating a higher level of GO dispersion and the suppression of GO agglomeration by adding hBN. Such a hybrid strategy in nanocomposites shows paramount values in the suppression of nanofiller agglomeration for preparing nanocomposites.