Temperature-sensitive aqueous surfactant two-phase system formation in cationic-anionic surfactant systems.
Temperature-induced aqueous surfactant two-phase system (T-ASTP), which was found to be of generic importance, was investigated in a series of conventional mixed cationic-anionic surfactant systems. On the basis of the investigations of turbidity, dynamic light scattering, transmission electron microscopy, and fluorescence resonance energy transfer, the formation of T-ASTP can be attributed to temperature-induced vesicle aggregation. Aggregated vesicles existed in the upper part, while the separated vesicles existed in the lower part. The phase separation temperature can be regulated by varying the surfactant composition or adding additives, such as d-sorbitol, urea, or NaBr. The hydrophobic interaction and cooperative effect between cationic and anionic surfactants played a significant role in the formation of T-ASTP.
Wang
Ke
K
Beijing National Laboratory for Molecular Sciences (BNLMS), State Key Laboratory for Structural Chemistry of Unstable and Stable Species, College of Chemistry and Molecular Engineering, Beijing, P. R. China.
Yin
Haiqing
H
Sha
Wei
W
Huang
Jianbin
J
Fu
Honglan
H