V. Arabli, A. Aghili
Shiraz Branch, Islamic Azad University,
Iran, Islamic Republic of
Keywords: graphene oxide, vinyl ester resin, mechanical properties, thermal stability, cure kinetics
Summary:
Abstract Graphene oxide (GO) was synthesized and nanocomposite was achieved using different contents of the GO and Vinyl Ester Resin (VE). The suspension was sonicated in order to prevent the agglomeration. Non-isothermal differential scanning calorimetry (DSC) technique was used to study the cure kinetics of neat VE and 0.3 wt% GO/VE nanocomposite. Kissinger and Ozawa equations were used to determine the activation energy (Ea). The Ea values of the cured GO/VE nanocomposite showed a decrease with respect to the neat VE. It is concluded that GO has a catalytic effect in the cure reaction. The glass transition temperature (Tg) was obtained from the maximum peak temperature of the loss factor curve. The Tg was increased by nearly 10 °C by the addition of 0.4 wt% GO to VE. Tensile mechanical tests were studied and the nanocomposite of 0.3 wt% GO/VE showed higher elongation and tensile strength. This percent (0.3wt% GO/VE) selected for non-isothermal differential scanning calorimetry to study the cure kinetics. Scanning electron microscopy (SEM) was studied to discern the surface features and dispersion of GO. The thermal stability of the cured VE and its nanocomposite was investigated with Thermogravimetric analysis (TGA). The char yields increased with the addition of 0.3, 1.5, and 3 wt% of GO to the Vinyl ester resin. The addition of GO improved the polymer flame retardancy and thermal resistance.