Separation Efficiency of Two SEC Packings: Comparison of Chromatographic, Thermodynamic, and Fractal Parameters

Abstract

The size-exclusion chromatographic (SEC), thermodynamic, and fractal behavior of two organic packings, named TSK-Gel H HR and TSK-Gel H XL , has been compared in order to assess their separation efficiency. The different experimental elution trends of five solvent/polymer systems have been evidenced through the universal calibration curves, and the existence of secondary mechanisms (such as adsorption) has been quantified by the chromatographic partition coefficient K p . From a 573 ORDER REPRINTS thermodynamic point of view, the swelling and crosslinking degrees have been evaluated and compared in the two gels assayed. Moreover, the values of some fractal parameters (fractal dimension of the surface and available pore size) provide support for the chromatographic and thermodynamic results. The comparison of all findings reveals that, in general, more solute -gel adsorption effects (higher K p values) occurs in the TSK-Gel H XL packing due to its higher crosslinking degree, lower swelling degree, and lower fractal dimension of the surface than in TSKGel H HR . In consequence, the latter packing offers a better potential resolution for polymer characterization by SEC.