The name is absent

(^a)
1

0.1

0.01

βfσ³∕A

0.001

0.0001

W⁵

0        0.2       0.4       0.6       0.8        1

q

Figure 6.8: (a) Interaction force between the two grafted monolayers in the absence of
free polymer as a function of the compression ratio (q = H∕2Hq) for p_gσ² = 0.01 (■), p_gσ²
= 0.03 (A) and p_gσ² — 0.1 (▼), at fixed N_s = 101. (b) Interaction force between the two
grafted monolayers in the absence of free polymer as a function of the compression ratio for
N_g = 51 (■), N_g = 101 (a) and N_g = 151 (▼), at fixed p_gσ² = 0.1.

(b)
1

0.1

0.01

βfσ³∕A

0.001

0.0001

10⁵

О 0.2      0.4      0.6      0.8       1

q

6.3.4 Interaction between two grafted monolayers in the pres-

ence of free polymer

The presence of free polymer around the grafted monolayers significantly affect
their structure and the interactions between them. For large separations between
them, they do not interact and behave as two independent monolayers immersed in
the free polymer solution. These monolayers and the free polymer interpenetrate each
other and the monolayers are compressed. The degree of interpenetration depends
upon the chain lengths of the grafted (N_g) and free (Nf) polymers, grafting density
(p_g) and the bulk free polymer density (pf) for σ_g = σf(= σ), where σ_g and σf are the
segments sizes of the grafted and free polymer chains, respectively. As all the polymer

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