6533b859fe1ef96bd12b7676

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A phenomenological theory of the Phase Distribution Chromatography (PDC)-separation effect is outlined and a theoretical equation for the measured PDC-calibration curves is given. Assuming a reversible-thermodynamical equilibrium in the polystyrene-PDC-column, only a relatively small part of the measured PDC-calibration curves could be explained: namely those running below their tangents. In order to explain the whole sigmoidal shape of the experimental curves, a theory of steady state in the system sol/gel was developed assuming deformation of the polymer coil near the gel front due to the stress related to the velocity gradient. The resulting dynamical flow-equilibrium differs highly from the reversible-thermodynamic one at suitable low column temperatures. It leads to two typical calibration regions explaining the resolution power of the PDC-column as a function of temperature. Analysis of the first one (reversible-thermodynamical) starts with a three-parameter partition function and leads to two contributions of the heat of transfer of a P-mer from the gel into the sol of the column. These results are compared with those of Schulz, von Gunner and Gerrens, and of Schulz and Horbach. In this way a physical interpretation of the three parameters in the partition coefficient of the P-mer in the system gel/sol of the PDC-column can be given.