The name is absent

surfaces and becomes almost uniform except in the vicinity of the surfaces where the
chains are depleted.

Figure 6.6: Segment density profiles of the two grafted monolayers (N_s = 101, p_gσ² =
0.03) at separations, (a) H = 70 σ and (b) H = 50 σ.

Figure 6.7b shows the interaction force between the two monolayers (N_g = 101, p_gσ² —
0.03) as a function of the separation between them. At large separations, the indi-
vidual monolayers are unperturbed as they do not know about each other and the
interaction force is zero. The monolayers start interacting when the separation be-
tween them is about twice the brush height of the individual unperturbed monolayers.
We can denote the height of a single unperturbed monolayer as Hq and define a com-
pression ratio q as H∕2Hq. For chains in an implicit good solvent, Hq ~ N_gpⁱ_gⁱ.
As the monolayers approach each other, the interaction force is purely repulsive as
f > 0 for all q < 1. Figure 6.8 shows the interaction force between two monolay-

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