| Full text | |
| Author(s): |
Total Authors: 4
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| Affiliation: | [1] Univ Sao Paulo, Fac Anim Sci & Food Engn, Dept Food Engn, Pirassununga, SP - Brazil
[2] PSL Res Univ, ESPCI Paris, Lab Phys Therm, 10 Rue Vauquelin, F-75231 Paris 5 - France
[3] Univ Parsis Diderot Paris 7, Lab Matiere & Syst Complexes, UMR 7057, Case Courrier 7056, F-75205 Paris 13 - France
Total Affiliations: 3
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| Document type: | Journal article |
| Source: | COLLOID AND INTERFACE SCIENCE COMMUNICATIONS; v. 23, p. 1-5, MAR 2018. |
| Web of Science Citations: | 2 |
| Abstract | |
This paper investigates water sorption and dehydration of model synthetic clay (Laponite) and highlights the large differences with natural Na-smectite clays. Measurements were done by combining for the first time thermogravimetric analysis and X-ray diffraction methods on Laponite powders stored in atmospheres with controlled relative humidity. Laponite exhibits a very good reproducibility of the sorption diagram and appears as the most hygroscopic among Na-smectites. The interlayer distance increases from 11 to 20 angstrom when the ratio r = n(H2O)/n(Na) increases from 2 to 22, in agreement with recent numerical simulations. The desorption process, in this range of r, in isothermal conditions follows a first order kinetics with two regimes around r{*} = 7 which is close to the coordination number of Na+ ions in concentrated NaCl solution. Activation energies and frequency factors are derived for the two regimes of desorption and discussed in relation with stability of the cationic complex. (AU) | |
| FAPESP's process: | 12/24047-3 - Physical properties of films based in biopolymers reinforced with laponite |
| Grantee: | Germán Ayala Valencia |
| Support Opportunities: | Scholarships in Brazil - Doctorate |
| FAPESP's process: | 13/07914-8 - FoRC - Food Research Center |
| Grantee: | Bernadette Dora Gombossy de Melo Franco |
| Support Opportunities: | Research Grants - Research, Innovation and Dissemination Centers - RIDC |