Structure reorganization in montmorillonite gels during drying
The structure evolution of montmorillonite gels, during drying by evaporation, has been studied by scanning electron microscopy (SEM) after hypercritical drying with liquid CO2. Fresh Fe3+1 electrolytes allow clay particles to aggregate to floes with a structure consistent with diffusion-limited aggregation. Compression under the capillary stresses, during evaporation, leads to gelation. During further drying by evaporation, the Fe bonding is strong and prevents the complete collapse of the gel into a parallel stacking of clay plates. On the contrary, such a collapse occurs more easily when fresh Fe electrolyte has not been added.
KeywordsPolymer Microscopy Electron Microscopy Clay Scanning Electron Microscopy
Unable to display preview. Download preview PDF.
- 1.J. Zou andA. C. Pierre,J. Mater. Sci. Lett. 11 (1992) 664.Google Scholar
- 2.T. A. Witten Jr. andP. Meakin,Phys. Rev. B 28 (1983) 5632.Google Scholar
- 3.H. Van Olphen andJ. J. Fripiat, “Data Handbook for Clay Minerals and other non-Metallic Minerals”, (Pergamon, Oxford, 1979).Google Scholar
- 4.A. S. Michaels andJ. C. Bolger,I. & E. C. Fundamentals 1 (1962) 24.Google Scholar
- 5.J. Fricke,J. Non-Cryst. Solids 100 (1988) 169.Google Scholar
- 6.J. Zou andA. C. Pierre,J. Can. Cer. Soc. 60 (1991) 51.Google Scholar
- 7.R. W. Ford,Drying, (MacLaren and Sons, London, 1964).Google Scholar
- 8.W. D. Kingery andJ. Francl,J. Am. Ceram. Soc. 37 (1954) 596.Google Scholar
- 9.I. L. Thomas andK. H. Maccorkle,J. Colloid Interface Sci. 36 (1971) 110.Google Scholar
- 10.A. C. Pierre, “Introduction aux procédés sol-gel”, Ch. 4 (Septima, Paris 1991).Google Scholar
- 11.P. J. Flory,J. Am. Chem. Soc. 63 (1941) 3083.Google Scholar
- 12.A. V. Blackmore,Aus. J. Soil. Res. 11 (1973) 75.Google Scholar