Revised state diagram of Laponite dispersions
| Autor: | Taco Nicolai, Jean François Tassin, Philippe Mongondry |
|---|---|
| Rok vydání: | 2005 |
| Předmět: |
chemistry.chemical_classification
Chemistry Aggregation rate Mineralogy Salt (chemistry) Light scattering Surfaces Coatings and Films Electronic Optical and Magnetic Materials Biomaterials Colloid Colloid and Surface Chemistry Chemical engineering Homogeneous State diagram Dispersion (chemistry) Structure factor |
| Zdroj: | Journal of Colloid and Interface Science. 283:397-405 |
| ISSN: | 0021-9797 |
| DOI: | 10.1016/j.jcis.2004.09.043 |
| Popis: | We propose a state diagram of charged disk-like mineral particle (Laponite) dispersions as a function of the Laponite concentration (C) and the concentration of added salt (C(s)), based on simple observation and light-scattering measurements. At low C or high C(s) the dispersions separate into two domains due to sedimentation of Laponite aggregates, while at high C and low C(s) they form homogeneous gels that do not flow upon tube reversal. The aggregation rate and the structure factor of the Laponite dispersions is determined with light scattering as a function of C and C(s). We discuss in detail the controversy on the origin of gelation of Laponite dispersions in the absence of added salt. We argue that aggregation rather than glass formation causes gelation. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect