The practice of adding micron sized inorganic filler particles to reinforce polymeric materials can be traced back to the early years of the composite industry. With synthetic methods that can produce nanometer sized fillers, resulting in an enormous increase of surface area, polymers reinforced with nanoscale particles should show vastly improved properties. Yet, experimental evidence suggests that a simple extrapolation of the design paradigms of conventional composites cannot be used to predict the be-havior of nanocomposites. The origin of these differences between conventional and nanocomposites is still unknown. This, unfortunately, precludes yet any rational design.Though some property improvements have been achieved in nanocomposites, nanoparticle dispersion is difficult to control, with both thermodynamic and kinetic processes playing significant roles. It has been demonstrated that dispersed spherical nanoparticles can yield a range of multi-functional behavior, including a viscosity decrease, reduction of thermal deg-radation, increased mechanical damping, enriched electrical and/or magnetic performance and control of thermomechanical properties. Especially the decrease in viscosity is advantageous for injection-molding op-erations. Facile tuning of nanocomposite Tg could thus allow us to control the usable temperature range of these materials. Again, the physics under-pinning this behavior remains unresolved, primarily due to the poor understanding of the effects that particle/matrix interactions have on the composite behavior. This project aims at overcoming these deficiencies by a twofold strategy. This project will bring together a critical mass of scientists, from atomistic to finite-element modeling. The goal is to develop, implement and validate multi-scale methods to compute the mechanical, thermochemical and flow behav-iour of nano-filled polymeric materials – based on the chemistry of selected model systems.