Preparation of Silica Microcapsules by Sol-Gel Method in W/O Emulsion
Spherical silica microcapsules whose average diameter was 3.6 <I>μ</I>m were synthesized by the sol-gel method in W/O emulsions containing an anionic surfactant at a high water to surfactant molar ratio. Special agitational conditions are needed to prepare spherical silica microcapsules. The properties of the resulting silica microcapsules were determined by Fourier-transform infrared spectroscopy and scanning electron microscopy. As the spherical silica particles have a hollow core structure, hydrolysis and condensation of TEOS occur at the micellar periphery, and the diameter of the water droplets in the W/O emulsion at a high water to surfactant molar ratio (<I>Wo</I>) are micron sized.
- Journal of chemical engineering of Japan
Journal of chemical engineering of Japan 31(5), 808-812, 1998-10
The Society of Chemical Engineers, Japan