title: Comparative studies on the micellization of sodium bis(4-phenylbutyl) sulfosuccinate and sodium bis(2-ethylhexyl) sulfosuccinate and their interaction with hydrophobically modified poly(acrylamide).
abstract: The micellization process of sodium bis(4-phenylbutyl) sulfosuccinate (SBPBS) has been studied compared to that of sodium bis(2-ethylhexyl) sulfosuccinate (AOT) by surface tension, steady-state fluorescence, microcalorimetry, dynamic light scattering (DLS), and transmission electron microscopy (TEM) measurements. Meanwhile, the interaction of these two surfactants with hydrophobically modified poly(acrylamide) (HMPAM) was investigated. The results show that the surface tension at the critical micelle concentration (cmc) of SBPBS and the micropolarity probed by pyrene in SBPBS aggregates are both larger than those of AOT. The enthalpy change of micellization (DeltaH(mic)) of AOT is endothermic, while it is exothermic for SBPBS. Strong pi-pi interaction among the adjacent phenyl groups of SBPBS molecules is likely the cause for the above properties of SBPBS. Moreover, vesicles are observed for AOT and SBPBS by DLS and TEM, especially for AOT, whose micelle-vesicle transition has been first confirmed by its calorimetric curve. In the surfactant-HMPAM systems, the critical aggregation concentration (cac), the saturation concentration of aggregation (C(2)), and the thermodynamic parameters of binding have also been determined. The conclusion may be drawn that the binding strength of SBPBS onto HMPAM is stronger than that of AOT.
authors.affiliation: Key Laboratory of Colloid and Interface Science, and Joint Laboratory of Polymer Science and Materials, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, People's Republic of China.
authors.forename: Yanru
authors.initials: Y
authors.lastname: Fan
authors.forename: Yajuan
authors.initials: Y
authors.lastname: Li
authors.forename: Guangcui
authors.initials: G
authors.lastname: Yuan
authors.forename: Yilin
authors.initials: Y
authors.lastname: Wang
authors.forename: Jinben
authors.initials: J
authors.lastname: Wang
authors.forename: Charles C
authors.initials: CC
authors.lastname: Han
authors.forename: Haike
authors.initials: H
authors.lastname: Yan
authors.forename: Zhixin
authors.initials: Z
authors.lastname: Li
authors.forename: Robert K
authors.initials: RK
authors.lastname: Thomas