The name is absent

Figure 6.14: (a) Locus of the critical value of a at which the interaction force between
the grafted monolayers becomes attractive for different relative segment sizes of the grafted
and free polymers: σ_g — σy(B), σ_g — l.lσ∕(∙), and σ_g = 1.2σj(⅛). The bulk free polymer
density, pf σ j = 0.6 and N_s = 101. σf = σ. (b) Scaling relation for the locus of the critical
value of a for different relative segment sizes of the grafted and free polymer: N_g = 101, σ_g =
σy(B); N_g = 101,σ_g = l.lσ∫(∙); N_g = 101,σ_s — 1.2σ∕(∆); and N_g = 151,σ_g = σ∕(⅜)∙
σf = σ. The bulk free polymer density, Pfσj = 0.6. σy = σ.

the critical value of a where the interaction force between the two monolayers turns
from purely repulsive to attractive follows the scaling relation, p_gy∕N_gβ³ oc a~².

6.4 Conclusions

Modified iSAFT density functional theory has been extended to study the struc-
ture of polymer brushes in the absence∕presence of free polymer solvent. In the
absence of the solvent or for ‘dry brush’, the structure is governed by the grafting
density and the segment-segment interactions of the polymer chain. The theory is in
good quantitative agreement with the MD simulation results in literature and follows

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