Liquid chromatography at the critical adsorption point (LCCAP) of high molecular weight polystyrene: pushing back the limits of reduced sample recovery

Abstract

AbstractLow sample recovery may be one limiting parameter in Liquid Chromatography at the Critical Adsorption Point (LC-CAP) of high molecular weight polymers. We aimed at playing on different experimental parameters in LCCAP of high molecular weight polystyrenes (PS) in order to reach maximum sample recovery. The nature of adsorli and desorli, the temperature, the nature of the column surface and the pore size were studied as regard to their influence on sample recovery. Evaporative Light Scattering was used for detection. We demonstrated that almost all experimental parameters are correlated and that in any case, the lower the adsorli content, the better the sample recovery. Molecular weight limit for good sample recovery could be pushed from as low as 100 000 for the THF/cyclohexane mixture and silica columns to above 1 000 000 for the DCM/n-hexane mixture and amino-silica columns.