Preparation, mechanical properties and fracture of the optimal surface modified alumina silicate based ceramic particles reinforced polymer composites

Polyester resin was replete with a high percentage of surface-modified fly ash ceramic particles using a combination of sol-gel and hand lay-up techniques. The characterizations of the fly ash powder showed that the ceramic particles were the spherical solid type and composed of both the glass and crystal phases. The composites were subjected to the mechanical and Charpy impact tests as well as the fracture studies. Consequently, the hardness was found to increase linearly. The required results derived from both the mechanical and impact tests indicated that a positive correlation was obtained. The tensile strength of the higher percentage was lowered due to the existence of large size particles and the elongation at break was decreased due to the restriction of the polyester molecular chain flexibility. Finally, the fracture surfaces of the excellent compositions indicated that the particles had strongly bonded with the polyester matrix. This is mostly due to the existence of reasonable (-OH) groups on the particle surfaces.