ADSORPTION OF ALKYLXYLENESULFONATES ON ALUMINA - A FLUORESCENCE PROBESTUDY

Changes in the positions of the sulfonate and the methyl groups on the aromatic ring of alkylxylene-sulfonate were found to produce a marked effect on the micellization and adsorption at the solid/liquid interf ace of alkylxylenesulfonates. Fluorescence spectroscopy was used to pr obe the microstructure of the micelles and hemimicelles of the surfact ants. The studies showed the p-xylenesulfonate micelles to be less pol ar and the p-xylenesulfoante micelles and hemimicelles to have higher aggregation number than the m-xylenesulfonate micelles and hemimicelle s, respectively. Based on results obtained, steric constraint to the p acking of these molecules in the aggregates was determined to be the m ain reason for the differences in the micellization and hemimicellizat ion of the surfactants.