The name is absent

confinement, hence the figure only shows the profiles near one of the confining surfaces.
As for linear polymer chains, the star polymer chains also do not prefer to be near the
surface since they lose their configurational entropy. Hence, the chains are depleted
near the surface at lower packing fraction, η_avg = 0.1. After the depletion layer,
the segment density profile becomes flat and reaches its bulk value (‰⅛) in the
confinement. In the figure, the segment densities are normalized by their bulk values.
When the number of chains in the confinement increases, for example at η_aυg = 0.3 in
the figure, the chains push each other and pack against the surface. This packing effect
leads to enhancement of the polymer chains near the surface. The overall segment
density profile is oscillatory in the vicinity of the surface, with ^lσ^, being the period
of the oscillations. These oscillations die around z = 3 σ and the profile becomes flat
at its bulk value. The segment density profile at the intermediate packing fraction of
0.2 clearly shows the competition between the packing and configurational entropie
effects. The figure also compares the results obtained from modified iSAFT with the
simulation results of Yethiraj and Hall [264] and the results from the DFT approach
followed by Malijevsky et. al. [268]. The results from modified iSAFT are in excellent
agreement with the simulation results. At higher packing fractions of 0.2 and 0.3, the
contact densities predicted from modified iSAFT are in better agreement with the
simulation data than the DFT approach by Malijevsky et. al.

Even for the athermal linear polymer fluids, the segment density profiles are gov-
erned by the competition between the packing and configurational entropie effects.

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