Thermodynamic study of polystyrene-n-alkane systems by inverse gas chromatography
| Autor: | Luisa Bonifaci, Gian Paolo Ravanetti |
|---|---|
| Rok vydání: | 1993 |
| Předmět: |
Alkane
chemistry.chemical_classification Activity coefficient Chromatography Organic Chemistry General Medicine Entropy of mixing Biochemistry Analytical Chemistry Homologous series chemistry.chemical_compound chemistry Volume (thermodynamics) Volume fraction Inverse gas chromatography Phase diagram |
| Zdroj: | Journal of Chromatography A. 641:301-307 |
| ISSN: | 0021-9673 |
| Popis: | Phase diagrams of systems containing high-carbon-number n -alkanes (up to n -pentatriacontane) and polystyrene were studied in the temperature range from 190 to 250°C. Experimental data obtained for low-carbon-number alkanes by inverse gas chromatography were extrapolated taking advantage of the linear relationships between ln V g 0 (specific retention volume at 0°C) and the inverse of the temperature and between ln V g 0 and the number of carbon atoms for homologous series. The resulting activity coefficients and interaction parameters were typical of systems with a poor compatibility. The Gibbs free energy of mixing (Δ G m ) for polystyrene-alkane systems was calculated, with the Flory-Huggins χ parameter assumed to be independent of the composition. The Δ G m vs . alkane volume fraction curves exhibited a shape corresponding to solution instability at low concentrations of both components. On this basis the phase diagram of the system polystyrene-alkanes was calculated. |
| Databáze: | OpenAIRE |
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