Figure 5.1: (a) Segment density profiles for the A block (solid black curve), B block
(dashed black curve) and the total segment density of the copolymer (solid gray curve) for
L = 6σ. (b) Segment density profiles for the A block for L = Db = 10.2σ (solid black
curve) and L = 15σ (dashed black curve). For the diblock copolymer, N = 8 and f,∕kT =
0.289.
(b)
1
z∕σ
5.3.1 Bulk diblock copolymer melts
The calculation of the lamellar density profiles of the diblock copolymer melt is a
one dimensional (I-D) problem. Hence the modified iSAFT equations for the segment
density profiles are solved in I-D with periodic boundary conditions at the two ends
of the computational domain. For N = 8 and e∕kT = 0.289, the density profiles of
the two blocks are shown in figure 5.la. The width of the computational domain is
fixed to 6σ. The total segment density of the copolymer is also shown in the figure.
The density profile of the individual blocks is sinusoidal. The total segment density
is constant except at the interface of the two blocks. There is depletion in the total
124