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Mechanical Properties of Colloidal Gels

Published online by Cambridge University Press:  21 February 2011

W.-H. Shih
Affiliation:
Department of Materials Science and Engineering, and Advanced Materials Technology Program, Washington Technology Center University of Washington, Seattle, WA 98195
J. Liu
Affiliation:
Department of Materials Science and Engineering, and Advanced Materials Technology Program, Washington Technology Center University of Washington, Seattle, WA 98195
W. Y. Shih
Affiliation:
Department of Materials Science and Engineering, and Advanced Materials Technology Program, Washington Technology Center University of Washington, Seattle, WA 98195
S. I. Kim
Affiliation:
Department of Materials Science and Engineering, and Advanced Materials Technology Program, Washington Technology Center University of Washington, Seattle, WA 98195
M. Sarikaya
Affiliation:
Department of Materials Science and Engineering, and Advanced Materials Technology Program, Washington Technology Center University of Washington, Seattle, WA 98195
I. A. Aksay
Affiliation:
Department of Materials Science and Engineering, and Advanced Materials Technology Program, Washington Technology Center University of Washington, Seattle, WA 98195
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A colloidal suspension can be either dispersed or flocculated depending on the interaction between the colloidal particles. If the interaction is repulsive, particles can relax to the minimum of the potential due to their neighboring particles, and the system can reach an equilibrium dispersed state. In the case of attractive interaction, particles form aggregates that settle to the bottom of the container. As the concentration of particles is increased, the overcrowding of the aggregates produces a continuous network throughout the suspension before they settle and a colloidal gel is formed. A major difference between a colloidal gel and a colloidal suspension is that the gel can sustain finite stress and is therefore viscoelastic. Previously we studied the storage modulus and the yield strain of boehmite gels and found that they are related to the particle concentration in a power-law fashion [1]. Similar scaling behavior of the shear modulus was found for other colloidal particulate networks by Buscall et al. [2]. We developed a scaling theory [1] which successfully explains the experimental results on boehmite gels. The theory further predicts that there can be two types of power-law behavior depending on the relative elastic strength of the clusters to that of the links between clusters within the gel network. Furthermore, there can be a crossover from one type of behavior to the other as the particle concentration is varied.

Type
Research Article
Copyright
Copyright © Materials Research Society 1989

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References

REFERENCES

1. Shih, W.-H., Shih, W. Y., Kim, S. I., and Aksay, I. A., preprint.Google Scholar
2. Buscall, R., Mills, P. D. A., Goodwin, J. W., and Lawson, D. W., J. Chem. Soc. Faraday Trans. I., 84, 4249 (1988).Google Scholar
3. Dietler, G., Aubert, C., Cannel, D. S., and Wiltzius, P., Phys. Rev. Lett., 57, 3117 (1986).Google Scholar
4. Kantor, Y. and Webman, I., Phys. Rev. Lett., 52, 1891 (1984).Google Scholar
5. Shih, W. Y., Aksay, I. A., and Kikuchi, R., Phys. Rev. A, 36, 5015 (1987).Google Scholar