Probing mechanical properties of graphene oxide/epoxy composites based on nano indentation technique

Abstract

The silanized graphene oxide (KH-GO) with different mass fractions was dispersed in epoxy resin by a solution blending method and resin transfer molding process. The nano indentation method was used to test the micromechanical properties of GO/epoxy composites with different mass fractions, and the effect of GO on the hardness of epoxy matrix composites was quantitatively determined, and the influence of adding KH-GO on the thermal mechanical and bending properties of epoxy resin was discussed by dynamic thermal mechanical and universal strength machine tests. The experimental results show that the thermal and mechanical properties of composites are improved with the increase of the amount of KH-GO. Especially, when the content of KH-GO was 0.3%, the bending strength (125.4 MPa), hardness (281.0 MPa), and glass transition temperature (99.6°C) of composites reached the highest. It was proved that the composites showed its excellent performance and the silane coupling agent was successfully grafted to the graphene oxide by covalent bond, which effectively improved the interface compatibility of the reinforcing body and the matrix and was related to good dispersibility in the epoxy resin. This method is simple and effective, providing a certain reference value for the enhancement of the mechanical properties of the next generation of nanocomposites.