“…It was observed that higher density HGMs remained intact in the PPMA matrix and increasing HGM density resulted in a reduction in mechanical properties. SFC as a form of polymeric composite materials (PCMs) typically possess numerous properties, such as low density, good thermal insulation, low coefficient of thermal expansion, high strength-to-weight ratio, good acoustic properties, low moisture absorption and good resistance to hydrostatic pressure [ 12 , 13 , 14 , 15 , 16 ]. Most of these special properties are caused by various factors, such as filler sizes, type of binder used, volume fraction considered, void fraction, filler/matrix interface and condition of manufacturing, which yields unique applications [ 8 ].…”