Influence of SiO₂@PANI Core/Shell Particles on Mechanical Properties, Electrical Properties, and Thermal Aging of Epoxy Resin

The pristine epoxy resin exhibited its low fracture toughness and low thermal stability. The using of functionalized liquid rubber led to an improvement of fracture toughness along with a reduction of thermal stability of epoxy resin. So to simultaneously improve both the fracture toughness and the thermal stability of epoxy resin the silica/PANI core-shell particles have been used as an additive. The core/shell particles were prepared by decorating the surface of silica with polyaniline via a chemical oxidation reaction. The silica was extracted from rice husk via some simple steps. The high-speed mechanical stirring was utilized to enhance the uniform dispersion of core/shell particles in epoxy resin. The composite was formed at room temperature using DETA as a curing agent. The mechanical characteristics and thermal stability of composite were examined including tensile strength, flexural strength, fracture toughness, and TGA. The tensile strength was improved by 16,16% from 40,9 MPa to 47,51 MPa by adding core/shell particles to epoxy resin. The thermal stability of epoxy resin was also improved with presence of core/shell particles. In particular, the fracture toughness was improved by 52,8% from 1,12 MPa.m(-1/2) to 1,87 MPa.m(-1/2). The electrical conductivity of epoxy resin with SiO2@PANI Core/Shell increased by 178 times when compared with pristine epoxy. The SEM image was also used to provide the evidence for the improvement in fracture toughness, and mechanism.