Effect of tween-80 on the control of particle size and shrinkage properties of nanoscale α-alumina synthesized by sol-gel processing

The concept of tailored interfaces has been applied to the synthesis of nanoscale alpha-Al2O3. Tween-80 (poly-oxyethylene(20) sorbitan monooleate, T-80) was used as a surface modifier in the sol-gel process for this purpose. High-resolution transmission electron microscopy study of the powder obtained with T-80 confirmed the particle size of alpha-Al2O3 (similar to55 nm) and morphology (spherical). The exothermic peak temperature in the differential thermal analysis was shifted to a lower temperature (similar to917degreesC) when the powder was derived from a T-80 modifier content of 10 wt%. X-ray diffraction showed that the of-Al2O3 phase was the major phase that existed in modifier-derived powder that was sintered at 1000degreesC. The experiments, based on linear shrinkage, indicated that the powder with T-80 (10 wt%) could be densified at a low temperature.