Abstract: The concentration distribution of polymer solution prior to gelling has been numerically studied with self-consistent field theory (SCFT). As a result, under specified conditions (system size, interactions between polymer segments, solvent and wall, solution concentration), the depletion/adsorption transition will take place. It was demonstrated that the depletion/adsorption transition depends on the difference of the interaction parameters between polymer segment and wall, and that of solvent and wall. The reciprocal of the polymer chain length was found to have a linear effect on the differences of the interaction parameters at the transition point. Furthermore, when the capillary’s diameter is not large enough, the linear fitting constants are related with the system dimension and the average volume fraction of the polymer solution. The polymer chains with smaller molecular weight approach closer to the wall when the polymer is polydisperse. Increasing the polymer concentration and chain length, choosing better solvents or reducing the systemdimension is beneficial to the solution uniformity.

Key words: Capillary, Self-consistent field theory, Polymer solution, Concentration distribution