Pragmatic multiscale modelling of bone as a natural hybrid nanocomposite

A multiscale modelling strategy is proposed to predict the mechanical properties of polymer-inorganic hybrid nanocomposites. In particular, high volume fractions of oriented mineral plates in a ductile polymer matrix offer the potential of an attractive balance of stiffness and toughness. Bone is used here as a natural example of such a material, since it has a hierarchy of structures at all scales of dimension, and is an excellent subject for multiscale materials modelling. The key step in the model is to predict the individual properties of the component materials by a self-consistent mean-field method from their molecular structure. This allows the synergistic interaction of mineral and polymer at the large number of interfaces in a nanocomposite to be modelled as an energy sharing process, whose main effect is upon the polymer modulus. The interface-modified mechanical properties are then used in composite models at higher scales to predict the nonlinear stress–strain curve to failure as a function of the main variables of mineral volume fraction (MVF) and particle aspect ratio.