Hydrodynamic and micellar properties of sodium alkyl benzene sulphonates

Abstract

This paper provides hydrodynamic data and micellar properties of some sodium alkyl benzene sulphonates. The free energy of micellisation. as deduced from experimental data, is compared with that calculated from the structural parameters and shows that these sulphonates form spherical and ellipsiodal micelles in aqueous medium.The ease of micellisation and micelle size increases as one goes from sodium decyl to sodium hexadecyl benzene sulphonates. The solubilisation data of n-octane and ethyl benzene in aqueous sodium alkyl benzene sulphonate solutions above the cmc indicates that aliphatic hydrocarbons when solubilised reside within the micellar core whereas aromatic hydrocarbons reside in the micellar core as well as in the annular space between hydrodynamic shear surface and surface of the micellar core,