Enhancing Mechanical and Thermal Properties of Nanocomposites Using Novel Silica/Mg(OH)₂ Green Composite Nanoparticles

This study aimed to assess the impact of different weight percentages (0.25%, 0.5%, and 0.75%) of novel green nanoparticles on the thermal and mechanical properties of polymer-based nanocomposites. These novel nanoparticles are composed of a silica core and an external component of Mg(OH)2. The external component was synthesized in three different green synthesis techniques, using lemon juice, to achieve different geometries, i.e. dot, beam, and flake. It should be noted that nanoparticle characteristics are verified using XRD and SEM analysis. According to the experiment, adding nanoparticles to the polymer led to significant improvements in its flexural strength (43%), flexural modulus (47%), and mode I fracture toughness (32%). Additionally, the thermal characteristics have demonstrated a notable enhancement in flammability properties. Based on the UL-94 test, nanocomposite specimens were classified as V-0 and V-1, whereas neat samples are NC. Also, incorporating nanoparticles into the polymer can increase LOI by up to 31.4%. The TGA test showed that adding flake composite nanoparticles retains 33% of the specimen mass, while only 2% of neat samples remain. In general, the green composite nanoparticles led to achieving the common properties of both nanomaterials. To clarify, the silica core improved mechanical properties, while an external Mg(OH)2 component enhanced the polymer’s thermal properties.