Mechanical Properties of Multiscale Graphene Oxide/Basalt Fiber/Epoxy Composites

Abstract

This work was carried out to study the effects of silane functionalization of graphene oxide (GO) nanoplatelets and their loadings on the mechanical properties of basalt fiber (BF)/epoxy composites. At first, the GO nanoplatelets were organically modified by grafting of N-(3-trimethoxysilylpropyl)ethylenediamine (3-TMSPED) compound. The Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX), and thermal gravimetric analysis (TGA) results demonstrated that silane compound can be covalently grafted to the surface of GO. The multiscale silanized graphene oxide (SGO)/BF/epoxy composites with various weight percentages of SGO in the matrix (0-0.5 wt.% in the step of 0.1) were fabricated. According to the experimental data, the 0.4 wt.% SGO-filled composite showed the maximum improvement by 18 %, 59 %, and 61 % in the tensile, flexural and compressive strengths of BF/epoxy composite, while the maximum improvement by 46 %, 54 %, and 66 % in the tensile, flexural and compressive moduli, respectively was observed for the 0.5 wt.% SGO-filled composite. Additionally, the SGO was more effective in mechanical property enhancement of fibrous composites in comparison with GO, due to its silane-functionalization. From the fracture surface examination of the specimens, it was found that the incorporation of GO or SGO improved the BF-epoxy interfacial bonding. A theoretical model based on Euler-Bernoulli beam-based method was utilized to predict the compressive properties of composites, which was in an excellent agreement with the experimental data.