Phase diagram from SCFT for blends s1 (top), s2 (middle), and s3 (bottom) as described in Table I. Blue = cylinders, green = gyroid, red = lamellar, black = disordered.
Phase diagram at constant temperature (χN s 1 = 15). The solid black lines mark the phase boundaries obtained by Court and Hashimoto.13
Morphologies obtained χN = 35 for various blend compositions φ A and at various box lengths. For clarity, only the interfaces between block domains are shown.
Variation of free energies of the woodpile and cylinder phases with box size at blend composition φ A = 0.1833. The error bars give the standard deviation of the data.
Structure factor of each of the (a) gyroid for L box = 19.5, φ A = 0.2250, (b) cylinders for L box = 19, φ A = 0.2250, and (c) cocontinuous phase for L box = 25, φ A = 0.2267.
Order parameter Q as a function of box size for the gyroid, cylinders and cocontinuous morphologies for blend compositions 0.2250 ≤ φ A ≤ 0.2300; χN = 35.
Variation of free energy with box size for different morphologies for blend composition φ A = 0.230 and χN = 35: (a) from MC-EXE method and (b) from TI method (showing free-energy difference relative to the χN = 0 system).
Free energies of the gyroid and cocontinuous phases relative to that of the cylinder phase for various blends at (a) χN = 40, (b) χN = 35.
End-to-end distances for B block of asymmetric chains as.
Local density of the majority domain. Red portions indicate regions of the minority domain. Green (low density) pockets in the “bulk” of the blue domain evidence packing frustration. (a) Gyroid phase for L box = 19.5, φ A = 0.2250, (b) cocontinuous phase for Lbox = 25, φ A = 0.2267, and (c) cylinder phase for Lbox = 19, φ A = 0.2250.
Isosurfaces of A-block fraction = 0.5 for the gyroid phase with L box = 19.5, φ A = 0.2250: grey surface represents overall A-monomers in the blend, green mesh for symmetric chains, and red mesh for asymmetric chains. (a) Density calculated as the number of symmetric chain A beads over total number of beads. Points 1 and 2 show nodes that the symmetric chains occupy, 3 is a node which such chains do not occupy, and 4 refers to a tube of the that such chains occupy. (b) Density calculated as number of A beads of all chains over total number of beads.
Chain lengths used in the SCFT study. N is the “relative” degree of polymerization and f is the fraction of monomer A in each component.
Morphologies obtained using DPD by varying χN for blend compositions 0.2233 ≤ φ A ≤ 0.2300. “Def” refers to morphologies with defects, C = cylinders, G = gyroid, PL = perforated lamella, and Cocon. = concontinuous phase.
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