Atomistic Simulations of Drops and Nanoparticles Interacting with Surface Grafted Polymeric Layers

Surface-grafted polymer molecules have been extensively employed for surface modifications. Bottom-up surface processing with well-defined polymeric structures has become increasingly important in many current technologies. Polymer brushes, which are polymer molecules grafted to a substrate by its one end at close enough proximity (thereby ensuring that they stretch out like the "bristles" of a toothbrush), provide an exemplary system of materials capable of achieving such a goal. Here we use Molecular Dynamics (MD) simulations to study the interplay of interactions between nanoparticles, solvent drops and surface-grafted polymeric layers under various system conditions. Our study focused on different systems in order to understand the following phenomena: (1) the wetting dynamics of brush grafted surfaces and the viscoelastic nature of the associated brush conformational changes, (2) polymer-insoluble solvophilic NP assembly in brush grafted surfaces and the steric interactions driven establishment of direct contacts between a NP and a polymer layer (highly phobic to the NP), and (3) the filtration and valving properties of nanoconfined grafted polymer surfaces under interaction with drops of binary liquids.