Surfactants for producing low interfacial tensions: III. Di and tri n‐alkylbenzenesulfonates

The synthesis of several di and tri n‐alkylbenzene‐sulfonates is described. Low interfacial tensions can be obtained against alkanes by using these materials as surfactants. The low interfacial tension properties of these surfactants are shown to be profoundly influenced by the presence or absence of an alkyl group in the ortho position relative to the sulfonate group and also to depend on the length of this alkyl chain relative to other chains in the molecule. Surfactants where this chain is relatively long tend to give their lowest interfacial tensions against the lowest molecular weight alkanes and also to be effective at lower surfactant molecular weight.