Ordering Nanoparticles with Polymer Brushes
arXiv:1711.06198 · doi:10.1063/1.5006048
Abstract
Ordering nanoparticles into a desired super-structure is often crucial for their technological applications. We use molecular dynamics simulations to study the assembly of nanoparticles in a polymer brush randomly grafted to a planar surface as the solvent evaporates. Initially, the nanoparticles are dispersed in a solvent that wets the polymer brush. After the solvent evaporates, the nanoparticles are either inside the brush or adsorbed at the surface of the brush, depending on the strength of the nanoparticle-polymer interaction. For strong nanoparticle-polymer interactions, a 2-dimensional ordered array is only formed when the brush density is finely tuned to accommodate a single layer of nanoparticles. When the brush density is higher or lower than this optimal value, the distribution of nanoparticles shows large fluctuations in space and the packing order diminishes. For weak nanoparticle-polymer interactions, the nanoparticles order into a hexagonal array on top of the polymer brush as long as the grafting density is high enough to yield a dense brush. An interesting healing effect is observed for a low-grafting-density polymer brush that can become more uniform in the presence of weakly adsorbed nanoparticles.
9 pages, 6 figures
References in corpus (7)
- Interaction potentials for soft and hard ellipsoids
- Dispersing Nanoparticles in a Polymer Film via Solvent Evaporation
- Morphology Selection of Nanoparticle Dispersions by Polymer Media
- Evaporation of Lennard-Jones Fluids
- Structure and Diffusion of Nanoparticle Monolayers Floating at Liquid/Vapor Interfaces: A Molecular Dynamics Study
- Interaction of charged patchy protein models with like-charged polyelectrolyte brushes
- Nanoparticle ordering in sandwiched polymer brushes