Hostname: page-component-7479d7b7d-fwgfc Total loading time: 0 Render date: 2024-07-12T13:18:48.209Z Has data issue: false hasContentIssue false
  • English
  • Français

Preparation of Porous Oxide Beads Using Polymeric Beads to Control Bead Size and Shape

Published online by Cambridge University Press:  28 February 2011

Anne B. Hardy ,
Wendell E. Rhine  and
H. Kent Bowen
Anne B. Hardy
Affiliation:
Ceramics Processing Research Laboratory,Massachusetts Institute of Technology,Cambridge,MA 02139
Wendell E. Rhine
Affiliation:
Ceramics Processing Research Laboratory,Massachusetts Institute of Technology,Cambridge,MA 02139
H. Kent Bowen
Affiliation:
Ceramics Processing Research Laboratory,Massachusetts Institute of Technology,Cambridge,MA 02139
Get access

Abstract

A method was developed for preparing silica gels by silicon alkoxide hydrolysis using water-swellable polymers to control the shape. A variety of polymer beads with different water absorbencies and different bead sizes were used. Silica beads in a wide range of sizes were prepared from polymer beads. The final bead size was dependent on the size and water absorbency of the beads, on the extent of reaction, and on the final density. It was shown that porosity could be formed in two regions. The silica beads contained pores of 3–4 nm that were attributed to the intrinsic gel structure. In addition, when large amounts of polymer were removed, additional porosity on the scale of 20–50 nm was formed. It was also shown that surface areas varied dramatically with calcining. For beads containing only small pores, surface areas varied from 400 m2/g to less than 0.2 m2/g as the calcining temperature was increased from 600°C to 1000°C. Beads containing porosity formed by removal of the polymer remained porous even after calcining at 1000°C.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 180: Symposium A – Better Ceramics Through Chemistry IV , 1990 , 1009
Copyright
Copyright © Materials Research Society 1990

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Hardy, A.B., PhD Thesis, MIT, 1988.Google Scholar
2. Hamling, B.H., U.S. Patent No. 3,385,915 (1968).Google Scholar
3. Card, R.J., Adv. Cer. Mater. 3 (1), 29 (1986).Google Scholar
4. Card, R.J. and O'Toole, M.P., J. Am. Ceram. Soc. 73 (3), 665 (1990).Google Scholar
5. McQuillan, B.W. and Reynolds, G., in Ultrastructure Processing of Advanced Ceramics, edited by Mackenzie, J.D. and Ulrich, D.R. (J. Wiley and Sons, New York, 1988), pp. 739–745.Google Scholar
6. Pentinghaus, H., J. Non-Cryst. Sol. 63., 193 (1984).Google Scholar
7. Seidell, A., Solubility of Organic Compounds. Vol. 2, 3rd ed. (D. Van Nostrand Co. Inc., New York, 1941) p. 148.Google Scholar
8. Unger, K.K., Porous Silica. Its Properties and Use as Support in Column Liquid Chromatography (Elsevier Science Publishing Co. Inc., New York, 1979), p. 41.Google Scholar
9. Iler, R.K., The Chemistry of Silica. Solubility. Polymerization. Colloid and Surface Properties. and Biochemistry (J. Wiley and Sons, New York, 1979), pp. 578–599.Google Scholar
10. Mackenzie, J.D., in Ultrastructure Processing of Ceramics. Glasses. and Composites edited by Hench, L.L. and Ulrich, D.R. (J. Wiley and Sons, New York, 1984).Google Scholar