and segment sizes may be needed to provide the necessary flexibility in fine-tuning
the structure of the thin polymer films. Therefore the objective of the current work
is to develop a general model, which can simulate these complex heteronuclear chain
architectures. However, the approach is still limited to flexible chains architectures
with no loops or cycles.
In previous chapters, modified iSAFT was successfully applied to study the struc-
ture of confined heteronuclear polymers such as diblock copolymers. However, in
these previous works, the formulation is derived only for linear heteronuclear chains.
In this work, the theory is extended in general such that it is applicable to complex
branched heteronuclear chain architectures. The derivation is presented in section 2.
To test the theory, modified iSAFT is applied to confined star-like branched poly-
mers, since they are nice stepping-stone model objects for studying systems where the
topology∕architecture of the molecule plays an important role [262, 263]. The results
from modified iSAFT and comparisons with the simulation results of Yethiraj and
Hall [264, 265] are discussed in section 3. The final section summarizes the important
features of the theory and the systems studied, with few concluding remarks.
7.2 Model and theory
The branched polymer molecule is modeled as a flexible chain of tangentially
bonded spherical segments. Each of the segments of the chain can be different (to
account for the heterogeneity in the chain structure). For the sake of simplicity,
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