A lattice self-consistent field study of self-assembly of grafted ABA triblock copolymers in a selective solvent

The effects of chain-grafting density, chain composition, and interactions between different species on the self-assembled structures and chain conformations of planar grafted ABA triblock copolymers in a solvent selective for the middle B-block are investigated systematically using 3-dimensional lattice self-consistent field calculations. Structures with one A-rich layer (S1Aa and S1Ab) and with two A-rich layers (S2A) are predicted and the corresponding formation conditions are identified. It is the competition between the entropy and enthalpy that results in the formation of different structures. The copolymer chain composition affects the balance between entropy and enthalpy, and therefore has a significant influence on the resulting structure and chain conformations. In structures S1Aa and S1Ab, the free A-blocks fold into the B-rich domain and the grafted A-rich domain, respectively, whereas in structures S2A the free A-blocks do not fold. Our results are compared with available experimental and simulation results of related systems. (C) 2018 Elsevier Ltd. All rights reserved.