Examples of Multiple Emulsions Using Polymeric Surfactants

Examples of Multiple Emulsions Using Polymeric Surfactants 

Several examples of W/O emulsions and W/O/W multiple emulsions based on the block copolymer of PHS-PEO-PHS, have been produced. As an illustration, a typical formulation of W/O/W multiple emulsion is described below, using two different thickeners, namely Keltrol (xanthan gum from Kelco) and Carbopol 980 (a crosshnked polyacrylate gel produced by BF Goodrich). These thickeners were added to reduce creaming of the multiple emulsion. A two-step process was used in both cases. 

The primary W/O emulsion was emulsified in an aqueous solution containing the polymeric surfactant Pluronic PEF127. A sample of the polymeric surfactant (2g) was dissolved in 16.2 g water containing a preservative by stirring at 5°C. 

The above multiple emulsion was prepared under the same conditions except that Carbopol 980 was used as a thickener (gel). In this case, no MgS04 was added as the carbopol gel was affected by electrolytes. The aqueous PEF127 polymeric surfactant solution was prepared by dissolving 2g of the polymer in 23 g water  

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