Autor: |
Dashuang Fan, Zhiguo Hao, Peizhu Zheng, Jihua Zhao, Weiguo Shen |
Jazyk: |
angličtina |
Rok vydání: |
2020 |
Předmět: |
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Zdroj: |
Arabian Journal of Chemistry, Vol 13, Iss 1, Pp 2925-2933 (2020) |
Druh dokumentu: |
article |
ISSN: |
1878-5352 |
DOI: |
10.1016/j.arabjc.2018.08.002 |
Popis: |
The influence of water-soluble polyethylene glycols PEG200 on the properties of sodium bis(2-ethylhexyl)-sulfosuccinate (AOT) water-in-isooctane microemulsions has been investigated by conductivity measurement and isothermal titration microcalorimetry (ITC). The percolation temperatures (Tp), the thermodynamic properties of droplet aggregation and the interaction enthalpy (−ΔHφ) between droplets for AOT/water/PEG200/isooctane with different PEG concentrations and a fixed molar ratio of water to surfactant ω = 22.2 were determined. Based on a two-stage thermodynamic approach of the percolation, we obtained the fusion enthalpy (ΔHf0) of the close contact droplets by a combination of the droplet aggregation enthalpy (ΔHag0) and −ΔHφ. It was found that both (−ΔHφ) and (ΔHf0) varied with the concentration of PEG200 (cPEG) and had the extreme value at cPEG = 25 g L−1. This phenomenon was interpreted by the variation of interface rigidity due to the varied distributions of added PEG200 between the water pool and the surfactant interface. Keywords: Conductance percolation, Thermodynamic parameter, Interaction enthalpy, Fusion enthalpy, Isothermal titration microcalorimetry |
Databáze: |
Directory of Open Access Journals |
Externí odkaz: |
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