The name is absent

■1.8

Figure 5.10: Excess surface free energy of the copolymer as a function of the effective
film thickness, for symmetric phases. For the diblock copolymer, N = 8 and e∕kT = 0.289.
For surfaces, e_w∕kT = 0.3.

and f_w can tell us if the anti-symmetric phases will be stable or not. This is useful
to calculate the minimum affinity (e_w) of the surface towards the A block over which
only the symmetric phases are stable.

5.4 Conclusions

Modified iSAFT has been applied to study the lamellar microstructures of the
symmetric diblock copolymers, in the strong segregation limit. For bulk copolymer
melts, the equilibrium lamellar period, D;, increases with the increase in the incom-
patibility of the two blocks of the copolymer. The increase in the number of segments
of the diblock copolymer also increases D⅛, which follows a power law dependence on

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