Tensile Properties of Epoxy Composite Reinforced With a Low Fraction of Nanosilica Fillers

Epoxy nanocomposite resins filled with spherical silica particles about 10-15 nm in diameter were investigated for their tensile properties as a function of silica content. Nanoparticles were dispersed with 0.5%, 1% and 3% ratio in weight respect to the nano matrix. The epoxy resin system is made of diglycidyl ether of bisphenol A (DGEBA), Epon 828, with jeffamine D400 as the curing agent. Ultrasonic and mixing in two stages with different speed were used to get a homogenous dispersion of silica fillers in epoxy resin. The nanocomposite shows increase in tensile strength with addition of silica content in comparison with neat epoxy. The obtained results show 15% increase in young modulus for resin filled with 1% nanosilica compared with neat epoxy. Moreover, in 1% silica content nanocomposite has brittle behavior with 21% decrease in fracture toughness compared with neat epoxy.