Nonyl-phenyl-poly- surfactants

The above emulsion system is fairly simple, since it is likely that the nonyl phenyl and propylene oxide chain is on the oil side of the interface, whereas the poly(ethylene oxide) chain is on the aqueous side of the interface. The hydrodynamic thickness of the surfactants, given above, is much smaller than the droplet radius and hence these sterically stabilized emulsions may approximate hard-sphere dispersions very closely (with an effective radius = R + 8 ). This can be tested by fitting the data to the hard-sphere model suggested by Dougherty and Krieger (40,41). 

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