Long-Chain Alkylsilane-Modified Porous Silica Beads as GPC Packings

Abstract

A series of silica gels having various molecular weight exclusion limits has been modified by reaction with octadecyltrichlorosilane. Toluene being used as moving phase and hydroxyl-end blocked polydimethylsiloxane as solute, the chromatographic process on these modified silica packings is mainly controlled by size exclusion; an additional absorptive retention can still be observed with the low molecular species. Thus, calibration in this case should be performed using standard samples of the specific polymer to be determined.