COMPETITIVE INTERACTIONS OF PHENOL DERIVATIVES AND ALIPHATIC-ALCOHOLSFOR ALKENYL AND DIOL SILICA SURFACES

A thermodynamic equation is used to analyze the retention behavior of phenolic solutes at low modifier concentrations on alkenyl and diol ch emically modified silica packings. These materials were prepared by at taching alkenyl and diol ligands with four, six, eight and ten carbon atoms to the surface of LiChrosorb Si-60 silica. The thermodynamic ana lysis of the capacity ratios of various phenolic solutes measured at d ifferent concentrations of simple aliphatic alkohols (used as modifier s) in n-hexane have provided information about solute and solvent inte ractions with the alkenyl and diol modified silicas. This analysis sho ws that the solute-alcohol competitive interaction for the alkenyl bon ded phases changes significantly with chain length, whereas this effec t is not observed for the diol phases. Also, the influence of polarity and geometric structure of functional groups on solute retention have been examined.