Improved aqueous dispersion of silicon nitride with aminosilanes

Journal Article · Fri Nov 01 04:00:00 EST 1996 · Journal of the American Ceramic Society

DOI:https://doi.org/10.1111/j.1151-2916.1996.tb08729.x· OSTI ID:417780

Buchta, M A; Shih, W H ^[1]

---

1. 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, Journal Name: Journal of the American Ceramic Society Journal Issue: 11 Vol. 79; ISSN 0002-7820; ISSN JACTAW
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AQUEOUS SOLUTIONS
BULK DENSITY
CENTRIFUGATION
COLLOIDS
EXPERIMENTAL DATA
OPTICAL MICROSCOPY
PH VALUE
POWDER METALLURGY
SILICON NITRIDES
SLURRIES
SURFACTANTS
VISCOSITY