The ultral fine alpha-alumina powder has been successfully synthesized via two-step hydrolysis of
aluminum isopropoxide. Glucose and polyvinyl pyrrolidone were used as surfactants during the
appropriate processing step. The alpha-alumina powder was used as seed particles. Several synthesis
parameters, such as the amount of seeds, surfactants, and calcination temperature, were studied by X-ray
diffraction (XRD), Fourier transform infrared spectra (FTIR), Thermogravimetry-differential scanning
calorimetry (TG-DSC), scanning electron microscopy (SEM) and transmission electron microscopy (TEM).
The experimental results showed that glucose greatly lower the phase transformation temperature of
alpha-alumina by impelling the gamma-alumina transformed to alpha-alumina directly, and the seed
could improve the phase transformation rate of alpha-alumina, the polyvinylpyrrolidone have an effect
on preventing excessive grain growth and agglomeration of alpha-alumina powder. Comparatively well
dispersed alpha-alumina powder with particle size less than 50 nm can be synthesized through this
method after calcinations at 1000 C for 2 h.
The ultral fine alpha-alumina powder has been successfully synthesized via two-step hydrolysis ofaluminum isopropoxide. Glucose and polyvinyl pyrrolidone were used as surfactants during theappropriate processing step. The alpha-alumina powder was used as seed particles. Several synthesisparameters, such as the amount of seeds, surfactants, and calcination temperature, were studied by X-raydiffraction (XRD), Fourier transform infrared spectra (FTIR), Thermogravimetry-differential scanningcalorimetry (TG-DSC), scanning electron microscopy (SEM) and transmission electron microscopy (TEM).The experimental results showed that glucose greatly lower the phase transformation temperature ofalpha-alumina by impelling the gamma-alumina transformed to alpha-alumina directly, and the seedcould improve the phase transformation rate of alpha-alumina, the polyvinylpyrrolidone have an effecton preventing excessive grain growth and agglomeration of alpha-alumina powder. Comparatively welldispersed alpha-alumina powder with particle size less than 50 nm can be synthesized through thismethod after calcinations at 1000 C for 2 h.
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