Improved aqueous dispersion of silicon nitride with aminosilanes
- Drexel Univ., Philadelphia, PA (United States). Dept. of Materials Engineering
The addition of a standard fiberglass surfactant, 3-aminopropyltriethoxysilane (APS), improves whisker and powder dispersion of silicon nitride aqueous suspensions. Aqueous suspensions of APS-coated silicon nitride have lower viscosities, increased consolidation, and higher dried green-body densities compared to uncoated silicon nitride in suspensions with pH values {le}8. The APS coating shifts the isoelectric point (IEP) of silicon nitride to a more basic value, dependent on the concentration of APS coating. Suspension pH measurements indicate that APS extracts one hydrogen ion for each APS molecule either chemisorbed on the particle surface or dissolved in the solution. Optical microscopy reveals that dilute suspensions coated with APS at pH 10 are qualitatively more dispersed than uncoated silicon nitride at pH 7. The results show increased dispersion of APS-coated silicon nitride in acidic environments, with a 12% increase in green density under identical wet-pressing conditions.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 417780
- Journal Information:
- Journal of the American Ceramic Society, Vol. 79, Issue 11; Other Information: PBD: Nov 1996
- Country of Publication:
- United States
- Language:
- English
Similar Records
Improved dispersion of silicon nitride whiskers
Development of short-range repulsive potentials in aqueous, silicon nitride slurries