RETENTION BEHAVIOR OF CARBOXYLIC ACIDS ON HIGHLY CROSS-LINKED POLY(STYRENE-DIVINYLBENZENE)-BASED AND SILICA-BASED CATION EXCHANGERS

摘要

A highly cross-linked porous poly(styrene-divinylbenzene) resin was reacted with sulfuric acid to give strong cation-exchange resins with capacities from 0.2 to 1.9 mequiv./g. The retention behavior of mono- and dicarboxylic acids on these resins was compared with results obtained from silica-based cation exchangers functionalized with alkylsulfonic acid or phenylsulfonic acid groups. The contribution of different retention mechanisms like ion exclusion, hydrophobic interaction and adsorption to the separation of the analytes on these chromatographic supports was discussed. Additionally the applicability of silica-based cation exchangers was tested in the field of silage analysis.