Effect of filler treatment on the mechanical properties of silica filled epoxy composites

In this research, filler treatment of silica was performed using (3-Aminopropyl)trimethoxysilane. Silica filled epoxy composites of 0, 2.5, 5, 7.5 and 10 vol.% were prepared. The mechanical properties of treated and untreated silica filled epoxy composites were characterized using tensile, flexural, hardness and impact testing methods. Filler treatment of silica increased the tensile, flexural and impact strength of the silica filled epoxy composites as well as their hardness. The effect of filler treatment on tensile and flexural strains could not be established due to insignificant testing data. The effect of filler treatment on the modulus of silica filled epoxy is negligible as the strength ofthe filler-matrix interphase has no significant effect on the modulus of the composites. From the DMA, fiiJer treatment showed to decrease the glass transition temperature. The estimated crosslink density of treated silica filled epoxy composites was lower than their untreated counterpart. From FTIR analysis, two new peaks emerged for the treated silica, signifying effective filler treatment.