Pickering emulsifier

Wolters, D., Meyer-Zaika, W., Bandermann, F., Suspension of polymerization of styrene with pickering emulsifiers, Macromol. Mater. Eng. 286 (2001) 94. 

Nanoparticles in the GML/tetradecane/water system could also be formed in the presence of clay particles. The authors assumed a Pickering emulsion-like stabilization by the clay particles which are of disk-like shape with about Inm thickness and 30 nm diameter. Detailed information about the stabilization mechanism within these systems remains, however, still to be obtained. The use of clay particles as stabilizers holds some promise with regard to the preparation of "emulsifier-free" systems which are very interesting for pharmaceutical purposes. Hydrolysis of the monoglyceride was, however, pronounced in these dispersions due to the comparatively high pH introduced by the clay particle suspension. 

Emulsified droplets and micelles/vesicles formed by surfactant and amphiphilic block copolymers are often used as soft templates (Figure 11.1a). An inorganic shell can be formed on these templates if certain attractive interactions exist between the inorganic species and template surfeces. Pickering emulsions -emulsions stabilized by inorganic nanoparticles instead of amphiphilic molecules -can be converted to hollow particles by connecting the nanoparticles to each other. The templates are finally removed by solvent extraction, calcination, or simple... 

For many years it was known that emulsions can be stabilized by solid fat particles that adsorb onto the water/oil interface. Such stabilization was called Pickering or mechanical stabilization. Recently, we reported that emulsifiers can help modify the fat particles and crystallize them (prior to forming the emulsion) into the a or P form. The modified particles will better wet the interface and will be better oriented to the interface and thus wiU better stabilize the emulsions. It was found that the best emulsion stability could be achieved if the fat particles that adsorb onto the oil droplets are crystallized by quench cooling so that the most hydrophilic a-form triglyceride particles will be obtained. These particles added to the W/O interface will stabilize the emulsion against coalescence. Garti and... 

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