The name is absent

merits. Although the segments of different types are of the same size (σ), they have
different long range attractions described by a square-well potential.

I ^aβ ɪf ɑ'_aβ ≤ Г ≤ q^z0"α∕3
<β{r) =

0 if r > yσ_crz3

where yσ_aρ is the width of the potential, which is fixed at 7 = 1.2. If e_aρ is positive,
segments a and в attract each other whereas if e_aβ is negative, they repel each other.
The surface is a flat wall and the surface-segment interaction is also given by the
square-well potential,

½_t(z) = <

0 otherwise

where z is the perpendicular distance from the surface. Again, if ε_α∏z is positive, the
surface attracts segment a whereas if ε_aw is negative, the surface repels segment a.

Figure 4.6a shows the density profiles of segments of type A and B of a symmetric
diblock copolymer “AAAABBBB” confined in a slit-like pore of width, H = 10σ. Like
segments, “A-A” and “B-B” attract each other with елл/кТ = l∙0 and евв/кТ = 0.5,
while “A-В” repel each other with елв/кТ = —0.5. The two surfaces preferentially
attract “A” with e_wA∣kT = 1.0 and repel “B” with e_wB∣kT — —1.0. The density
profiles obtained from the theory are compared with the simulation results from Cao
and Wu [112]. They are in good quantitative agreement. As expected, the density of

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