Synthesis of inorganic gels in a lyotropic liquid crystal medium. I. Synthesis of silica gels in lamellar phases obtained from non-ionic surfactants
Dabadie, T. ; Ayral, A. ; Guizard, C. ; Cot, L. ; Lurin, C. ; Nie, W. ; Rioult, D.
Springer
Published 1995
Springer
Published 1995
| ISSN: |
1573-4846
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|---|---|
| Keywords: |
lyotropic liquid crystal ; silica gel ; rheology ; low angle X ray diffraction
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| Source: |
Springer Online Journal Archives 1860-2000
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| Topics: |
Chemistry and Pharmacology
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| Notes: |
Abstract Some lamellar phases made with aqueous lyotropic liquid crystals were used as templates for the gelation of a silica inorganic network from tetramethylorthosilicate (TMOS). The aim was to synthesize materials with an anisotropic texture. Lamellar phases were obtained by using non-ionic surfacants. At first, structural, textural and rheological properties of the lamellar phases were studied. Then, the evolution of the system after introduction of the alkoxide, i.e., during the sol-gel transition, was followed by low angle X ray diffraction and rheological measurements. Finally, a textural study of dried gels was carried out. The formation of gels with a lamellar structure was analysed by compressing the total phase diagram (quaternary system) to a ternary system. The hydrolysis and condensation reactions of the TMOS are strongly influenced by the presence of the structured lamellar phase. Gelation seems to happen around the liquid crystal microdomains. A schematic model of gelation is proposed based on experimental observations.
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| Type of Medium: |
Electronic Resource
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| URL: |