Static and dynamic mechanical properties of vinylester resin matrix composites filled with fly ash

Vinylester resin matrix composites were prepared with a fly ash loading of 30, 40, 50 and 60 wt.-%. Flexural properties of the composites were investigated. It was found that the flexural strength was lowered in all the filled composites, but the flexural modulus showed a significant increase of 10, 57, 112% in case of 30, 40 and 50 wt.-% fly-ash-loaded composites respectively, compared to the neat resin. However, there was a decrease in the mechanical properties in case of 60 wt.-% fly-ash-filled composites. The dynamic mechanical analysis was carried out to obtain information about the matrix-filler interaction at the interface. The storage modulus value at room temperature was highest for the 50 wt.-% fly-ash-filled composites, corroborating with the observed flexural modulus value. The fractured surfaces were examined under SEM and were correlated with the mechanical properties. [GRAPHICS] Large voids evident in the 60 wt.-% fly-ash-filled composites.