The name is absent

these chains can either stretch away from the surface or collapse onto it. In fact,
the structure of these grafted polymer chains is responsible for the novel behav-
ior in their applications. Hence, a number of theoretical and experimental works
have focussed only on the structure of these grafted monolayers. The theoretical
works include the scaling theories developed by Alexander [51] and de Gennes [52],
SCFTs [180, 199, 227] and computer simulations using both molecular dynamics
(MD) [228, 229, 230, 231] and Monte Carlo (MC) [232, 233, 234, 235]. Experimen-
tally, the surface forces apparatus [236, 237], small-angle neutron scattering [238]
and neutron reflectivity [239, 240, 241] have been very important in determining the
structure of the polymer brushes. These approaches have been discussed in several
reviews in the literature. [242, 243, 244, 245]. Hence, determining the structure of
grafted monolayers in the absence/presence of the free polymer solvent using modified
iSAFT, is the first part of this work.

The outline of this chapter is as follows. The extension of modified iSAFT to
grafted polymer chains is presented in section 2. Section 3 presents the results and
discussions. As mentioned, first, the structure of the tethered monolayers in the
absence∕presence of an explicit free polymer solvent is investigated. The results are
compared with the MD simulation results from Grest and Murat [230, 231]. The
theory shows excellent agreement with these simulation results. Second, the force
of interaction when two of these monolayers are brought close to each other in the
presence of free polymer, is calculated. The effective interaction between the grafted

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