An investigation of TiO2 Nanoparticles Effect on Morphology, Thermal, and Mechanical Properties of Epoxy/Silica Composites

The objective of this study was to investigate the influence of titanium oxide (TiO2) nanoparticles on properties of epoxy/silica flour systems. To this end, nanocomposites containing different amounts of TiO2 were prepared by a casting method. Thermal and mechanical properties of the nanocomposites were investigated using dynamic mechanical thermal analysis (DMTA), thermo-gravimetrical analysis (TGA) and flexural test. Morphology of the nanocomposites i.e., dispersion and distribution of nanoparticles within the matrix was studied by scanning electron microscopy (SEM) and energy dispersive X-ray (EDX). Based on EDX results, it was found that nanoparticles' dispersion was rather good once very low content (1 wt%) of nanoparticles was added to the system. Conversely, poor dispersion was attained in high loadings of TiO2 due to the agglomeration of nanoparticles. SEM micrographs confirmed a brittle mode of failure for the nanocomposites by incorporation of nano TiO2. The TGA results indicated that the thermal stability of epoxy/silica flour system in the temperature range of 300-600 degrees C was enhanced by addition of 1 wt% TiO2 nanoparticles while no significant improvement was observed upon further increment in the nanoparticle content. The DMTA results also exhibited that storage modulus was increased with increasing TiO2 content, and tan d peak shifted to higher temperatures upon addition of 5% nanoparticles. The highest flexural strength was achieved by incorporation of 5 wt% of TiO2; however, beyond this limit, no further enhancement was observed in mechanical properties of the system due to the poor dispersion of nano TiO2 within the epoxy matrix. J. VINYL ADDIT. TECHNOL., 23:E216-E221, 2017.