Abstract
This research investigates the influence of single and hybrid mineral nanofillers on the morphological, thermal, and electrical properties of epoxy-based glass fiber composites. Nanocomposites were fabricated using hand lay-up technique, incorporating nano-calcium carbonate (CaCO₃) and nano-talc with particle size of 50 to 100 nm into an epoxy matrix with 5-ply E-glass/S-glass fiber. The study evaluates composites with 2-8 wt% of nano-CaCO₃, and hybrid systems containing nano-CaCO₃ (2-8 wt%) and nano-talc (1-4 wt%). Morphological analysis via Scanning Electron Microscopy (SEM) assessed nanofiller dispersion, while thermal properties were analyzed using Differential Scanning Calorimetry (DSC) for glass transition temperature (Tg). Electrical performance was evaluated through dielectric breakdown voltage (ASTM D149) and surface resistivity (ASTM D257). SEM analysis showed filler dispersion depended on concentration, with optimal distribution at 4-6 wt% before significant agglomeration at higher concentrations. DSC results revealed increased Tg with nanofillers, peaking for the composite with 6 wt% CaCO₃ and 3 wt% talc, indicating enhanced thermal stability. The dielectric breakdown voltage peaked at 17.6 kV for 2 wt% CaCO₃ and 1 wt% talc composite, while surface resistivity was highest for 4 wt% CaCO₃ and 2 wt% talc (73.74×1012Ω). All formulations maintained UL 94 V-1 flammability rating. The study concludes that the synergistic interaction between nano-CaCO₃ and nano-talc enables significant tailoring of thermal and electrical properties for advanced applications.