Thermodynamic Investigation of the Micellization and the Adsorption of Short Perfluoroalkylated Diols via Fluorescence Spectroscopy and Tensiometry
| Autor: | Régine Naejus, Céline Frochot, Marie-Laure Viriot, Alain Brembilla, Robert Coudert, Christine Damas |
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| Rok vydání: | 2001 |
| Předmět: |
Aqueous solution
Fluorescence spectrometry Fluorescence spectroscopy Surfaces Coatings and Films Electronic Optical and Magnetic Materials Gibbs free energy Biomaterials Surface tension chemistry.chemical_compound symbols.namesake Colloid and Surface Chemistry Adsorption chemistry symbols Organic chemistry Pyrene Physical chemistry Methanol |
| Zdroj: | Journal of Colloid and Interface Science. 241:188-198 |
| ISSN: | 0021-9797 |
| Popis: | The micellization and adsorption of two short chain perfluorodiols 3,3,4,4,5,5,6,6,6-nonafluorohexane-1,2-diol (nFHD) and 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctane-1,2-diol (tFOD) are examined from a thermodynamic point of view as a function of temperature and methanol content. The microenvironment of the fluorinated aggregates is evaluated by the fluorescence probe method using pyrene and a molecular rotor 1,1-dicyano-4-p-dimethylaminophenyl)-1,3-butadiene (DMAPhC). The formation of micellar aggregates being evidenced, the results are discussed in terms of the polarity and of the cohesion behavior of the micellar aggregates by taking into account the methanol (MeOH) effect. The critical micellization concentrations thus determined are compared with those given by surface tension measurements. Micellar and adsorption thermodynamic parameters such as Gibbs free energies, enthalpies, and entropies are determined together with the surface areas. The results are compared with literature data and discussed. A model for describing the adsorption process of the fluorinated compounds upon the influence of methanol is finally proposed. Copyright 2001 Academic Press. |
| Databáze: | OpenAIRE |
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