Nanoparticles as Universal Adhesives

Nanoparticles are shown to be able to act as effective adhesives capable of binding two soft materials together. We performed coarse-grained molecular dynamics simulations to study contact mechanics of hard and soft nanoparticles at the interfaces between two elastic surfaces. Our simulations have shown that a nanoparticle at the interface between two elastic substrates could be in a bridging or Pickering state. The degree of penetration of a nanoparticle into a substrate is shown to be determined by nanoparticle size, strength of nanoparticle-substrate interactions and nanoparticle and substrate elastic properties. Using the Weighted Histogram Analysis Method, we calculated the potential of mean force for separation of two substrates which interface was reinforced by deformable nanoparticles. These simulations show that interface reinforcement is a function of nanoparticle size and elastic modulus. In particular we have shown that the softest nanoparticles are most effective in interface reinforcement demonstrating about eight times increase in the work of adhesion.