The name is absent

0   12   3   4

Figure 5.12: Excess surface free energy of the copolymer as a function of the effective
film thickness. For the diblock copolymer, N = 8 and e∕kT — 0.289. For surfaces, e_w∕kT
= 0.3.

faces strongly prefer one of the blocks. A method has been suggested to find out if
the anti-symmetric phases are stable or not only by calculating the free energy and
segment density profiles of the symmetric phases.

The detailed segment density profiles of both the phases are qualitatively simi-
lar to the profiles obtained by MC simulations and support the discrepancies with
the previous SCF theories. The packing structure is observed near the surfaces, as
reported in these simulations. The fluctuations in the total segment density of the di-
block at the interfaces of the two blocks are also observed. These packing effects and
fluctuations can affect the relative stabilities of the symmetric and anti-symmetric
lamellar phases.

Recently, there have been a number of studies on the block copolymer in the

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