The name is absent

putational domain size was 40σ. Reflective boundary conditions were used on either
sides of the domain, with the center of the bilayer at one of the reflecting boundaries.
The initial guess for the calculation was step-like density profiles for all three types
of segments. Figure 4.5 shows the theory predictions for bilayer formation at a state
point, bulk segment density: p⅛σ³ = 0.68 and number fraction of solvent segments:
x_s = 0.442. The head groups have two peaks forming the ends of the bilayer while
the tail groups orient themselves between the head groups. The solvent molecules are
present on the outer sides.

4.3.3 Block Copolymers

Block copolymers are polymer chains comprised of two or more chemically distinct
polymer chains covalently bonded together. Since the covalent bond prevents the
macroscopic separation of the chemically distinct blocks, these copolymers undergo
microphase separations leading to heterogeneities in composition at the molecular
level. Thin films of block copolymers near preferential surfaces exhibit a wide variety
of microscopic structures which are exploited in a number of technological applications
like stabilization of nanoparticle dispersions [122, 123], copolymer-based lithography
and photonic materials [124].

Modified iSAFT can be applied to study the molecular structure of these het-
eronuclear chains. The block copolymers studied for this work are modeled as freely
jointed chains of tangent spheres, with different blocks having different types of seg-

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