Gas Diffusion in Polymer-Grafted <u>Nanoparticle</u> Melts

Polymer-grafted nanoparticles (PGNPs) are interesting candidates for gas separation applications owing mainly to the heterogeneous dynamic environment they provide for different gas components. To engineer the selectivity of these materials, it is crucial to understand the distribution and dynamics of the permeating gases. To this end, we use coarse-grained molecular dynamics simulations, systematically varying the size of the gas particles as well as the grafting density and chain length of the PGNPs. We track the motion of the individual gas particles, finding spatially heterogeneous dynamics, associated with the strong coupling between gases and the grafted polymers. In addition, we discuss possible scenarios of optimizing selectivity by manipulating the heterogeneous transport environment upon the addition of homopolymers of different lengths.