The name is absent

for hard chains developed by Hu et. al. [150] and the ideal free energy is based on
molecular density, as derived by Woodward. The use of molecular density introduces
an apparent complexity, as it is a 3N-dimension function and thus the numerical effort
to solve the resulting equations will scale exponentially with N.

On the contrary, modified iSAFT is more rigorous segment-based DFT as demon-
strated in previous chapter. Modified iSAFT was applied to study the microstructure
of block copolymers near selective (planar) surfaces. The density profiles obtained
were in excellent agreement with the simulation results. In this work, modified iSAFT
is applied to study the effect of confinement on the lamellar morphologies of symmet-
ric diblock copolymers.

The outline of this chapter is as follows. In section 2, the copolymer model system
and theoretical formulations is described. The lamellar morphologies of the symmetric
diblock copolymer thin films depend upon the lamellar period of these copolymers in
their bulk ordered melts (in the absence of the confining surfaces). Hence, modified
iSAFT is first applied to calculate the lamellar periods of the bulk copolymer melts
(in SSL). Next, these copolymer melts are confined between two parallel flat surfaces,
to form ultra-thin films. Both the surfaces preferentially attract one block and repel
the other block of the copolymer. The lamellar morphologies are investigated by
calculating the density profiles of the two blocks and the free energy of the copolymer.
The results and their discussions are presented in section 3. Section 4 summarizes
the conclusions from the current work.

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