The aim of the proposed experiment is to carry out a series of SANS measurements on chain-grafted silica nanoparticles prepared in our laboratory. In this experiment we plan to extract information on both the structure of the nanoparticles and of the grafted chains, through contrast variation measurements, in solution. Our aim is to extend these measurements, in future, to bulk systems. Generating model nanoparticles and investigating their structural behavior in solution, as proposed here, is a step towards an improved understanding of mechanical reinforcement. Ultimately this will enhance our ability to manipulate structures and control morphology to tailor properties.