Phase Behavior of Nonionic Surfactants

The most frequent emulsiflcation using phase inversion is known as the PIT (Phase Inversion Temperature) method [81-83] and occurs through a temperature quench. This method is based on the phase behavior of nonionic surfactants and the correlation existing between the so-called surfactant spontaneous curvature and the type of emulsion obtained. 

Bourrel M, Salager JL, Schechter RS, Wade WH (1980) A Correlation for Phase Behavior of Nonionic Surfactants. J Colloid Interface Sci 75 451-461... 

The preliminary results reported here indicate that the general changes induced in the PIT range may help to systematize the complex phase behavior of nonionic surfactants when they are combined with water and hydrocarbons. 

ZH2 Zhao, G. and Chen, S.B., Clouding and phase behavior of nonionic surfactants in hydrophobically modified hydroxyethyl cellulose solutions, Langmuir, 22, 9129, 2006. 

Section 3.3 Binary phase behavior of nonionic surfactants with RTILs... 

BINARY PHASE BEHAVIOR OF NONIONIC SURFACTANTS WITH RTILs... 

The binary phase behavior of nonionic surfactants in RTILs has been reviewed by Hao and Zemb [1], Greaves and Drummond [2], Inoue [3], and Dong and Hao [29]. The primary focus of these studies has been on the self-assembly of nonionic smfactants in protic RTILs such as ethylammonium nitrate (BAN) [30-33]. Araos and Warr [30] have studied the phase behavior of C EO in EAN and demonstrated that the overall phase behavior in EAN is very similar to that in water, although... 

PAN Pandif N.K. and Kanjia, J., Phase behavior of nonionic surfactant solutions in the presence of polyvinylpyrrohdone,/ t. J. Pharm., 141, 197, 1996. 

Key words Polyoxyethylene oleyl ether - liquid crystal - phase behavior of nonionic surfactant - small-angle X-ray scattering... 

Various kinds of self-organizing structures are formed in polyoxyethylene-type nonionic surfactant/water systems depending on temperature, surfactant concentration, surfactant structures, etc. [1,2], In previous studies on the basic phase behavior of nonionic surfactants, dodecyl chain surfactants have been mainly used. In longer chain nonionic surfactant systems, more phases appear and they are more important for practical applications, although the phase behavior have not been extensively studied. Polyoxyethylene oleyl ethers are biocompatible surfactants used for cosmetics, medicines, etc. The purity of commercially available oleic acid (cis-9-octadecenoic acid) is usually around 60% and the rest contains more than 50 kinds of other fatty acids [3]. Since conventional commercial polyoxyethylene oleyl ethers are synthesized from the low-purity oleic acid, it is difficult to figure out the basic phase behavior of the nonionic surfactants in water. 

Acknowledgement The author would like to express his sincere thanks to Prof. Gordon J. Tiddy of University of Salford for his helpful comments on the phase behaviors of nonionic surfactants. 

Figure 12.15 Phase behavior of nonionic surfactants and detergency three-phase temperatures versus n (right) and detergency (measured as reflectancy R) versus temperature (left)...

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