The name is absent

grafted monolayers, where the interactions can have an attractive minimum depending
upon the grafting density, relative chain lengths (α) and segment sizes (/3) of the free
and grafted polymers, and bulk free polymer density. First we considered cases where
the segment sizes of the free and grafted polymers are the same or β = 1. For a
given grafting and bulk free polymer density, the interaction force has an attractive
minimum if a is greater than a critical value. This critical value of a increases
with the increase in the bulk free polymer density at a given grafting density, and
decreases with the increase in the grafting density at fixed bulk free polymer density.
Furthermore, the locus of these critical values of a follows a scaling relation, p_gy∕N_g oc
a^-2, where the constant of proportionality is different at different bulk free polymer
densities.

In all these cases the segments of the grafted and free polymers are purely re-
pulsive and their sizes are the same, hence both of them are chemically identical.
The problem of repuslion∕attraction between the two grafted monolayers in the pres-
ence of chemically identical free polymer is theoretically and numerically equivalent
to the case of wetting∕dewetting of a free polymer on a chemically identical grafted
monolayer [207, 206, 208]. This equivalence breaks down when the free and grafted
polymers are not chemically identical. One such case have been considered, where
the segment sizes of the free and grafted polymers are not the same, or β ≠ 1. At
fixed grafting and bulk free polymer densities, increase in the (relative) segment size
of the grafted polymers increases the critical value of a. However, the locus of the

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