Skip to main content
SpringerLink
Log in

Electrical and infrared dielectrical properties of silica aerogels and of silica-aerogel-based composites

  • Solids And Materials
  • Published:
Applied Physics A Aims and scope Submit manuscript

Abstract

In this contribution we have studied the key electrical parameters of silica aerogels and of silica-aerogel-based composites, namely the dielectric constants ɛ, the dielectric losses tan δ (at 1 kHz), and the breakdown fields E b (at 50 Hz). For low-density bulk silica aerogels we find ɛ=1.25 and tan δ=0.0005. E b is about 500 kV/cm in quasi-homogeneous fields, and of the order of MV/cm in strongly inhomogeneous fields. The dielectric constants of partially densified aerogels increase linearly with density; their dielectric losses are relatively large and their breakdown fields are comparativiely low. The same results are found for aerogels in the form of settled materials, i.e. aerogel granules and powders in air. Acrylate-based aerogel composites with volume fractions larger than 70% have low dielectric constants but their losses are at least 10 times higher than those of low-density aerogels. These materials sustain high local fields in the MV/cm region, while in quasihomogeneous fields, breakdown occurs at about 100 kV/cm. Based on the present results and the interplay with other physical properties (low mechanical resistance, low thermal conductivity, adsorption of water, etc.), silica aerogels and silica aerogel-acrylate-based composites are predicted to have a low potential for electrical insulation.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. J. Fricke, A. Emmerling: Aerogels-Preparation, Properties, Applications, In Structure and Bonding 77 (Springer, Berlin, Heidelberg 1992) pp. 37–87

    Google Scholar 

  2. Proc. Third Int'l Symp. on Aerogels, Würzburg, Germany (1991), ed. by J. Fricke in J. Non-Crystalline Solids 145(1–3) (North-Holland, Amsterdam 1992)

  3. J. Fricke (ed.): Aerogels, Proc. First Int'l Symp. on Aerogels, Würzburg, Germany (1985), Springer Proc. Phys., Vol. 6 (Springer, Berlin, Heidelberg 1986)

    Google Scholar 

  4. J. Fricke: Aerogels. Sci. Am. 5, 68 (1988)

    Google Scholar 

  5. R. Vacher, E. Courtens, J. Pelouse: La Structure Fractale des aérogels. La Recherche, No. 220, 21, 426 (1990)

    Google Scholar 

  6. L.W. Hrubesh: In: Chemistry and Industry. Aerogels: The World's Lightest Solids. No. 24, pp. 824–827 (1990)

  7. B.M. Smirnov: Aerogels. Sov. Phys. Usp. 30(5) (1987)

  8. S.J. Teichner, G.A. Nicolaon, M.A. Viarini, G.E.E. Gardes: Inorganic Oxide Aerogels. Ad. Colloid Interface Sci. 5, 245 (1976)

    Google Scholar 

  9. V. Wittwer: J. Non-Crystall. Solids 145, 233 (1992)

    Google Scholar 

  10. J. Fricke: In Aerogels, Proc. 1st Int'l Symp. on Aerogels, ed. by J. Fricke, Springer Proc. Phys., Vol. 6 (Springer, Berlin, Heidelberg 1986) pp. 94–103

    Google Scholar 

  11. K.I. Jensen: J. Non-Crystall. Solids 145, 237 (1992)

    Google Scholar 

  12. S. Svendsen: J. Non-Crystall. Solids 145, 240 (1992)

    Google Scholar 

  13. G. Poelz: In: Aerogels, Proc. 1st Int'l Symp. on Aerogels, ed. by J. Fricke, Springer Proc. Phys., Vol. 6 (Springer, Berlin, Heidelberg 1986) pp. 176–187

    Google Scholar 

  14. W. Schwarz, V. Ebert, H. Geerds, K. Jungmann, S. Kirches, S. Koppe, F. Maas, H.J. Mundinger, G. zu Putlitz, J. Rosenkranz, W. Schäfer, G. Schiff, Z. Zhang, M.G. Boshier, V.W. Hughes: J. Non-Crystall. Solids 145, 224 (1992)

    Google Scholar 

  15. C. Hoang-Van, B. Pommier, R. Harivololona, P. Pichat: J. Non-Crystall. Solids 145, 250 (1992)

    Google Scholar 

  16. R. Gerlach, O. Kraus, J. Fricke, P.Ch. Eccardt, N. Kroemer, V. Magori: J. Non-Crystall. Solids 145, 227 (1992)

    Google Scholar 

  17. D.I. Santos, E.C. Ziemath, A.A. Silva, H.C. Basso, M.A. Aegerter: Cryst. Latt. Def. Amorph. Mat. 15, 381 (1987)

    Google Scholar 

  18. G.C. Crichton, P.W. Karlsson, A. Pedersen: IEEE Trans. EI-24, 335 (1989)

    Google Scholar 

  19. P. Pröckl: W.L. Gore & Associates GmbH, Pleinfeld, Germany (private communication)

  20. C.S. Walker: Capacitance, Inductance and Crosstalk Analysis (Artech House, London 1990)

    Google Scholar 

  21. The Feynmann Lectures on Physics: Vol. 2 (Addison-Wesley, Reading, MA 1967) pp. 6–12

  22. E. Kuffel, W.S. Zaengel: High-Voltage Engineering, Fundamentals (Pergamon, Oxford 1984) pp. 210–213

    Google Scholar 

  23. M. Kahle: Elektrische Isoliertechnik (Springer, Berlin, Heidelberg 1989) p. 7. Here, the function f(d/r) is actually given for a sphere of radius r separated by a distance d from the plane counter-electrode. For this configuration, the maximum field E b, max present at the center of the surface of the half-sphere facing the counter-electrode is very nearly the same as E b, max for the hemispherically shaped rod-configuration

  24. J.H. Mason: Proc. Inst. Electr. Eng. C 102, 254 (1955)

    Google Scholar 

  25. J. Fricke, J. Gross: Private communication (1992)

  26. H.R. Zeller, W.R. Schneider: J. Appl. Phys. 56, 455 (1984), and [10] therein

    Google Scholar 

  27. T. Woignier, J. Phalippou, M. Prassas: J. Mater. Sci. 25, 3118 (1990)

    Google Scholar 

  28. E.D. Palk (ed.): Handbook of Optical Constants of Solids (Academic, New York 1985), pp. 749–763; value of ɛ obtained from extrapolation of refractive index n in the far-infrared between \(\tilde v = 20{\text{ cm}}^{ - 1} \) and 100 cm−1 towards \(\tilde v = 0\)

    Google Scholar 

  29. H. Scholze: Glas (Natur, Struktur und Eigenschaften) (Springer, Berlin, Heidelberg 1977) p. 256

    Google Scholar 

  30. The absorption coefficient has been obtained from an oscillator fit to the observed transmission of a thermal oxide film with a thickness of 5100 Å on silicon substrate

  31. E. Kuffel, W.S. Zaengel: High-Voltage Engineering, Fundamentals (Pergamon, Oxford 1984) p. 219

    Google Scholar 

  32. Our Secondary Electron Microscopy (SEM) studies of aerogel granules with diameters ranging between 2 mm and 6 mm in Epoxy have shown that the granules are composed of a shell which consists of porous silicon dioxide impregnated with Epoxy, while the core consists of aerogel which might be partially densified. From density measurements it is also concluded that the aerogel particles embedded in Epoxy as well as in low-density polyethylene are densified and possibly impregnated with the matrix material

  33. W.R. Tinga, W.A.G. Voss, D.F. Blossey: J. Appl. Phys. 44, 3897 (1973)

    Google Scholar 

  34. R. Bartnikas (ed.): Engeneering Dielectrics, Vol. IIA, Electrical Properties of Solid Insulating Materials: Molecular Structure and Electrical Behaviour. ASTM Special Technical Publ. 783 (American Society for Testing and Materials, Philadelphia 1983) p. 61

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. ABB Management Ltd., Corporate Research Center Baden (CHCRC), CH-5405, Baden-Dättwil, Switzerland

    P. Brüesch, F. Stucki, Th. Baumann, P. Kluge-Weiss, B. Brühl, L. Niemeyer & R. Strümpler

  2. BASF Aktiengesellschaft, Farbenlaboratorium, Carl-Bosch-Strasse, D-67063, Ludwigshafen, Germany

    B. Ziegler & M. Mielke

Authors
  1. P. Brüesch
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. F. Stucki
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Th. Baumann
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. P. Kluge-Weiss
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. B. Brühl
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. L. Niemeyer
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. R. Strümpler
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. B. Ziegler
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. M. Mielke
    View author publications

    You can also search for this author in PubMed Google Scholar

Rights and permissions

Reprints and permissions

About this article

Cite this article

Brüesch, P., Stucki, F., Baumann, T. et al. Electrical and infrared dielectrical properties of silica aerogels and of silica-aerogel-based composites. Appl. Phys. A 57, 329–337 (1993). https://doi.org/10.1007/BF00332286

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF00332286

PACS

Search

Navigation