Generalizations on Surfactant Structure and Solubilizing Power

If one considers the relative solubilizing powers of the different types of surfactant with a given hydrophobic tail, it is usually found that they can be ordered as nonionics cationic anionic. The rationale for such a result is usually related to the supposed looser packing of the surfactant molecules in the micelles of the nonionic materials, making available more space for the incorporation of additive molecules without greatly disrupting the basic structure. 

The solubilizing power of amphoteric surfactants has not been as widely studied, or at least as widely reported, as that for the simpler ionic and nonionic materials. However, the available data indicate that they lie somewhere between the extremes in solubilizing capacity the exact results are probably more sensitive to the nature of the additive than those for the other classes of surfactants. 

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