Enhanced Fracture Toughness and Mechanical Properties of Epoxy Resin with Rice Husk-based Nano-Silica

This paper reports a novel approach to toughen epoxy resin with nano-silica fabricated from rice husk using a thermal treatment method with a particle size distribution in range of 40-80 nm. The nano-silica content was in the range, 0.03-0.10 phr, with respect to epoxy. The mechanical test showed that with the addition of 0.07 phr of rice husk based nano-silica, the fracture toughness of the neat epoxy resin increased 16.3% from 0.61 to 0.71 MPa m(1/2). The dynamic mechanical analysis test results showed that the glass transition temperature (T-g) of a 0.07 phr nano-silica dispersion in epoxy resin shifted to a higher temperature from 140 to 147 degrees C compared to neat epoxy resin. SEM further showed that the nano-silica particles dispersed throughout the epoxy resin prevented and altered the path of crack growth along with a change in the fracture surface morphology of cured epoxy resin.