Nonylphenol diethylene glycol ether

The presence of liquid crystal structures at both the w-o and o-w interfaces in multiple emulsions has been investigated by Kavaliunas and Frank (31). Microscopic examination of w/o/w emulsions between crossed polarizers revealed the presence of liquid crystal phases at both inner (w-o) and outer (o-w) interfaces in a w/o/w system composed of water, p-xylene and nonylphenol diethylene glycol ether. Liquid crystalline phases were also detected in o/w/o emulsions at both interfaces. The presence of these liquid crystal structures was found to improve the stability of the emulsions markedly. Matsumoto (32, 33) have concluded that the oil layers in w/o/w systems are likely to be composed of or contain,at least in proximity to the aqueous phase,multilamellar layers of the lipophilic surfactant used in the formulation this is postulated in part to explain the rate of volume flux of water through the oily layer. 

Figure 2.14 Phase diagrams for the three-component systems at 20° C a, water/ nonylphenol nonaethylene glycol ether/p-xylene b, water/nonylphenol diethylene glycol ether/p-xylene. From Friberg and Mandell [30] with permission.

The abihty to capture direct images of double-emulsion globules enables verification of the actual existence of the complex, three-phase system. The importance of visualization of double emulsions is seen in the work of Matsumoto and coworkers (1976) and their early success in developing a technique for preparation of stable double-emulsion systems. Similarly Kavaliunas and Frank (1978) used photomicrography to detect the structure of emulsions prepared with a water, p-xylene, and nonylphenol diethylene glycol ether system. As a result the authors were able to determine conditions favorable for the preparation of multiple emulsions, as shown in Figure 3.1. With polarized microscopy, the authors detected diffuse birefringence in multiple emul-... 

Figure 3.1 Photomicrograph of ap-xylene, water, nonylphenol diethylene glycol ether w/o/w emulsion (450x). Reprinted from Kavaliunas and Frank (1978) with permission from Elsevier.

Diethylene Glycol Momoethyl Ether Ethoxylated Dodecanol Ethoxylated Lauryl Alcohol Ethoxylated Tetradecanol Ethoxylated Nonylphenol Ethoxylated Pentadecanol... 

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