Oleophilic group

Molecular interaction between oleophilic groups and oil molecules... 

It is expected that the hydrophilic groups would make the compound less oleophilic, and thus decrease the octanol-water partition coefficient, or log P, which is also demonstrated in figure 6.4. When multiple functional groups are added, there are often interactions among them, so that the results are not simply additive. Figure 6.5 shows that each addition of chlorine to benzene from one to three would depress the water solubility of these benzene derivatives by a factor of six to eight, but the totally chlorinated hexachlorobenzene has a water solubility that is six orders of magnitude smaller than benzene. The partition coefficients show a very consistent pattern in parallel with... 

A qualitative term referring to the water-avoiding nature of a species (atom, molecule, droplet, particle). For emulsions hydrophobic usually means that a species exhibits an affinity for the oil phase over the aqueous phase. In this example, hydrophobic has the same meaning as oleophilic, but such is not always the case. A functional group of a molecule that is not very water-soluble is referred to as a hydrophobe . 

The surface activity of a smfactant is determined first hy the relationship between its hydrophihc and hydrophobic parts, or the hydrophi-lic-oleophihc balance. In the coiu e of interaction of a surfactant with an ohgomer, the surfactant s hydrophihcity and hydrophobicity, its structure and hydrophilic-oleophilic balance will change depending on its polarity and where in the surfactant molecule the active groups are located. But independently of this, such an interaction always results in increase of the surfactant solubUity in the oligomer and in decrease of its surface activity. 

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