Molecular dynamics simulation of electric-field-induced self-assembly of diblock copolymers.

The self-assembly of block copolymers under an external electric field was studied with a coarse-grained polarizable model that hybridizes the conventional polymeric coarse-grained model and Drude oscillator. The polarizability of the coarse-grained polymeric segment was reflected by the Drude oscillator. Applying this model, the alignment of the lamellar phase of the block copolymer melt under an external electric field was observed and the dynamic coupling information between chain polarization and interface orientation induced by the external electric field was obtained. It is demonstrated that the alignment of the lamellar structure along the electric field direction results from the polarizability difference of the polymer components. Finally, the transitions of phase structures of the block copolymer under an external electric field, from spherical phase to cylindrical phase, from gyroid structure to cylindrical phase, and from gyroid structure to lamellae phase were simulated. The specific evolution pathways were shown.