The name is absent

Figure 6.5: (a) Segment density profiles of hard chains tethered to a hard wall for N_g = 100
and p_gσ² = 0.1 in the presence of implicit solvent (∙) and explicit solvent with Nf = 2 (à),
Nf = 5 (■) and Nf = 10 (▼). Symbols are the simulation results from Grest [231] and
curves are the predictions from modified iSAFT. (b) Segment density profiles of polymer
brushes (Ng = 100 and p_gσ² = 0.1) and the free polymer solvent (Nf = 10, pfσ³ = 0.682)
from modified iSAFT.

and the grafting density is fixed to p_gσ² = 0.1. The calculations are done for three
different cases, Nf = 2, 5 and 10. The density of free polymer for all the three cases
is pfσ³ = 0.682, based on the overall monomer density in the system. Figure 6.5a
compares the density profiles of the polymer brush for these three cases with that in
the presence of an implicit solvent (Nf = 0). As can be seen from the figure, the
presence of an explicit solvent (free polymer) significantly affects the structure of the
brush. Since the chains are purely repulsive, the origin of the effect is solely due
to the entropie interactions. Due to volume exclusion, the explicit solvent molecules
compress the brush causing it to partially collapse compared to the case of implicit
solvent. This compression increases with the increase in the number of segments in

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