Percolation of high-density polymer regions in nanocomposites: the underlying property for mechanical reinforcement

Polymer nanocomposites have shown to exhibit improved mechanical properties compared to their pure host polymers. These property changes have been primarily attributed to the nature of polymer/nanoparticle interactions. Molecular dynamics simulations of model polymer nanocomposites have provided new insights into the molecular origin of property-changes in these nanocomposites. It was observed that addition of nanoparticles, induced adsorption of monomer segments onto the surface of nanoparticles creating high-density regions of polymer segments in the interfacial zones. A closer look into the morphology of these regions surrounding the nanoparticles revealed that mechanical reinforcement and changes in flow properties may be attributed to the formation of a percolated network of these high-density regions.