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Интеллектуальная Система Тематического Исследования НАукометрических данных |
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It is well known that in addition to the thermal annealing of block copolymer films and enforced domain orientation by electric field, vapors of various solvents are used as efficient tool for improvement of nanodomain structure in the films. In this paper, we propose computer simulations of lamellae forming diblock copolymer films swollen in solvent vapors. It has been demonstrated that initial swelling of parallel (with respect to the substrate) lamellae is affine and later on the structure reveals undulations resulted in lamella breaking. The final structure exhibits higher number of lamellae, each of them is thinner than lamella in the dry state. The simulation results are quantitatively consistent with experimental data.Also we study dense planar brushes of diblock copolymers physically attached to the substrate by end-groups. We predict stability of spatially ordered perpendicularly oriented domains which are separated from the substrate and the free surface of the film by homogeneous layers of different type. Depending on composition of the copolymer, various structures including hexagonally ordered “golf holes”, parallel “gullies” and “ridges”, and “stalactites” ordered with the symmetry of square or hexagonal lattices can be stable, see Figure. We analyze regimes of good and poor solvents for both blocks (non-selective solvents). Physical reason for perpendicular domain orientation is discussed. In the case of low “grafting” density, our results coincide with those reported in the literature.