Phase Behavior and Micropolarity of Ammonium Carboxylate Perfluoropolyether Reverse Micelles in Supercritical Carbon Dioxide
Phase Behavior and Micropolarity of Ammonium Carboxylate Perfluoropolyether Reverse Micelles in Supercritical Carbon Dioxide
复制标题
超临界二氧化碳中羧酸铵全氟聚醚反胶束的相行为和微极性
DOI：
10.1021/je900024f
复制
发表时间：
2009-04
影响因子：
--
通讯作者：
Ren, Qilong
中科院分区：
文献类型：
--
作者：
Su, Baogen;Yang, Yiwen;Xing, Huabin;Chen, Wei;Ren, Qilong
The phase behavior of the ammonium carboxylate perfluoropolyether (PFPE-NH4) + water + SCCO2 system was determined at temperatures of (308.15 to 328.15) K. The effects of water content and temperature on the polarity of the microenvironment in PFPE-NH4 reverse micelles in SCCO2 were investigated by UV−vis spectroscopy of a solvatochromic probe, methyl orange. The λmax of methyl orange in reverse micelles in supercritical CO2 was found to be between (408.2 and 430.7) nm under experimental conditions which indicated the micropolarity in reverse micelles was between cyclohexane and water. The micropolarity increased with the increase of water content after excess water appeared and increased with a decrease in temperature. This could be explained by more water dispersing into the surfactant aggregates with the increase of water content and the decrease of temperature.
