Modeling of the mechanical loading effects on the effective diffusive behavior of polymer matrix composites

In this study, the effect of a mechanical loading on the diffusion process in a polymer matrix composite is discussed. The application of an external loading is expected to modify the microstructure of the material and cause change in effective diffusive behavior as the diffusion in the polymer matrix is dependent on the free volume. On the basis of the free volume theory, the mechanical problem imposed on the representative volume element (RVE) is solved and then the volume fraction of free volume is determined. The effect of external mechanical loading on the moisture content and diffusion coefficient was first examined and finally the corresponding local stresses in the RVE are calculated.