The name is absent

there can be an attraction between the monolayers bringing the monolayers close
together [191, 192, 193]. As the monolayers approach each other, they force out the
two homopolymers, which then macrophase separate.

As mentioned, in all these applications the effective force of interaction between
two grafted monolayers determines stabilization or non-stabilization. If the size of
the grafting surfaces is significantly larger than the height of the grafted monolayers,
they can be treated as planar. A number of theoretical models have been developed
to study the interaction between these flat grafted monolayers in the presence of free
polymer. It is well known that interaction is purely repulsive for smaller free polymer
chain lengths (relative to the grafted polymer). However, attraction can occur for
large free polymer chain lengths. These theoretical models explore the origin of
the attractive forces between the Sterically hindered (flat) grafted monolayers in a
solution of long polymer chains. Earlier models either ignored the penetration of the
free polymer in the monolayer [194] or assumed complete penetration [195]. Vincent
et. al. [182] accounted for the entropically constrained interpenetration of the free
polymer in the grafted monolayers. However, they do not take into account the
compression of two monolayers as they approach each other.

Using statistical mechanics, the Gaussian chain model [53] for long polymer chains
can be solved using the self-consistent field theory (SCFT) introduced by Edwards [54].
In this approach, the molecular interactions are treated by a mean field which has to
be evaluated numerically. However, for polymer brushes an analytical expression can

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