The properties and applications of surfactants are determined by the balance between the lyophilic (‘‘solvent-loving’’  and lyophobic (‘‘solvent-hating’’) portions of the molecules. (There are also water-loving hydrophilic, water-hating hydrophobic, fat-loving lipophilic, and fat-hating lipophobic).

For that reason, such characteristics as solubility, surface tension reducing capability, critical micelle concentration (cmc), detergency power, wetting control, and foaming capacity may make a given surfactant perform well in some applications and less well in others. The ‘‘univer-
sal’’ surfactant that meets all the varied needs of surfactant applications has yet to emerge from the industrial or academic laboratory.