Synthesis and characterization of epoxy resin modified with nano-SiO2 and γ-glycidoxypropyltrimethoxy silane

Epoxy resin has been modified with nano-SiO2, standard SiO2 particles with diameter 30–40 nm and 3 μm, respectively, and γ-glycidoxypropyltrimethoxy silane. IR spectra indicated bonded stationary phase was formed with γ-glycidoxypropyltrimethoxy silane between nano-SiO2 and epoxy resin. Thermogravimetric analysis, impact strength and bulk resistivity tests showed that initial decomposition temperature Td, impact strength and bulk resistivity of epoxy resin-based composite increased and then decreased after nano-SiO2 content reached 4 wt.%, optimal values were 323 °C, 89.2 kJ m− 2 and 3.56 × 1014 Ω cm, respectively. Similar behavior had been also observed on standard SiO2/epoxy resin-based composites, optimal values were 308 °C, 17.13 kJ m− 2 and 2.80 × 1014 Ω cm, respectively. SEM analysis showed that toughness of nano-SiO2/epoxy resin-based composite and standard SiO2/epoxy resin-based composite also increased and then decreased after nano-SiO2 and standard SiO2 content reached 4 wt.%.