Self-assembly of Functionalized Nanoparticles in Ordered Phases of Block Copolymers

An emerging application of polymer nanocomposites is to generate self-assembly of nanoparticles leading to novel nanoscale materials with enhanced properties. As particle-based techniques, e.g. molecular simulation, are computationally intensive, we employ the self-consistent field theory (SCFT) combined with density functional theory (DFT) to examine the localization of nanoparticles in ordered domains of block copolymers. The nanoparticles are grafted with polymer chemically identical to either block of the copolymer. To ensure finite size of the particles and excluded volume interactions between species, the free energy is described using DFT. We study the localization of nanoparticles in lamellar and cylindrical morphologies. For lamellar phase, nanoparticles assemble either at the interface between two blocks or at the center of a block domain depending upon particle concentration and grafting density. In cylindrical phase, nanoparticles self-assemble at the center of the cylinders. The role of grafting density, particle size and composition on self-assembly behavior of particles in block copolymer is examined. The comprehensive understanding of factors affecting localization of nanoparticles enable us to control the particulate assembly for desirable material properties.