Abstract

Different preparation methods and formulations of epoxy nanocomposites have been examined. The effects of each parameter, such as different types of clay, different types of curing agent, and processing conditions (temperature, time, speed), on dispersion of the clay particles were evaluated using different means, such as field emission gun scanning electron microscopy (FEGSEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), and viscometer. Curing behavior was studied by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). Thermal properties of epoxy nanocomposites were evaluated by thermogravimetric analysis (TGA), limiting oxygen index (LOI). Dynamic mechanical properties were studied by dynamic mechanical analysis (DMA). Tensile, flexural, compression, impact, surface hardness and fracture toughness were also examined. A new method to disperse organoclay into epoxy without using solvent, and using high speed mixing (TS), is proposed. The results obtained from this study provide a good understanding of the relationship between the formulation, processing conditions and performance. Significant improvement in stiffness and storage modulus was observed in nanocomposites formulated with better dispersion using TS. However, the extent of the improvement of the nanocomposites' performance depends on the type of the clay and the curing agent. In addition, the processing conditions have great effects on the final properties of epoxy nanocomposites.