Study of Aggregate Density in Fumed Silica Suspensions

✍ Scribed by Thierry Aubry; Béatrice Largenton; Michel Moan

• Publisher: Elsevier Science
• Year: 1998
• Tongue: English
• Weight: 84 KB
• Volume: 202
• Category: Article
• ISSN: 0021-9797
• DOI: 10.1006/jcis.1998.5450

✦ Synopsis

ARTICLE NO. CS985450 NOTE Study of Aggregate Density in Fumed Silica Suspensions All samples studied in this work were prepared by dispersing silica particles in 1 M acetic acid, the pH being adjusted to 4 with addition of Viscometric and sedimentation experiments were performed on NaOH; the corresponding ionic strength of the medium has been shown to fumed silica suspensions at solid volume fractions f below 20%. be about 0.2 mol L 01 . At pH 4, Aerosil silica suspensions have been shown

The Newtonian viscosity and sediment volume of the suspensions to be stable (1, 2).

were studied as a function of f. All the experimental results are All samples were stirred for 2 days after preparation. Silica suspensions shown to be consistent with a dispersion microstructure, where prepared in these particular physico-chemical conditions are indeed one permanent low-density aggregates are the primary structural of the basic constituents of specific polymer -silica systems studied by units. Using a simple phenomenological model for both viscosity one of us ( 6) .

and sedimentation predictions, an average elementary permanent

The silica suspensions studied have a solid volume fraction ranging from aggregate is shown to have a solid volume fraction of about 20%. 0.2 to 20%.