Evaporation- and surface-induced morphology of symmetric diblock copolymer thin films: a multibody dissipative particle dynamics study

Abstract

We apply the multibody dissipative particle dynamics method to exhibit evaporation- and surface-induced morphology of diblock copolymer thin films. We find that when the interactions between A components and B components of the diblock copolymer are symmetric, it is easy to obtain a lamellar morphology perpendicular to the surface. On the contrary, if the interactions between A-blocks and B-blocks are asymmetric, it is easy to obtain a lamellar morphology parallel to the surface. Spherical morphology and disorder morphology are formed when the solvent vapour and surface effect are considered. The order parameter and the film thickness are calculated during the phase-separation process for characterising the film properties. The attractive solvent vapour increases the film thickness and impacts the film morphology of the interface. The attractive surface decreases the film thickness and impacts the film morphology near the surface. Our results are partially helpful for the control of film morphology and film thickness in such kind of materials.