Journal of Materials Science, Vol.31, No.18, 4779-4783, 1996
Silicone-Coated Alumina Powders by the Emulsion Technique
Alumina powders were prepared using an emulsion technique to chemically bond silanol-terminated poly dimethylsiloxane (PDMS or silicone) to the surface of alumina powders. Stable aqueous emulsions of silicone were prepared using Tween-80 surfactant. Transmission optical microscopy was used to measure the oil-droplet and coated-particle sizes. Fourier transform-infrared spectroscopy was used to quantify bonding between the silicone and the Al2O3. Coated powders were dry-pressed, and PDMS was compared to paraffin for dry-pressing behaviour and green strength. Densification studies were made on powders. X-ray diffraction and scanning electron microscopy were used to characterize the sintered ceramic.