Séminaires

Jean-Luc Bouvard (CEMEF)
Thermomechanical characterization and modeling of polymers under large deformation

The specific microstructure of polymers gives rise to a broad spectrum of mechanical behaviors. To capture such intricate structure properties, a wide variety of mechanical testing needs to be performed under a large range of temperatures, strain rates, and stress states. In this presentation, we will introduce a material model developed for large deformation. This model was built on a multiscale modeling strategy. Molecular dynamics simulations were performed to study the deformation mechanisms of an amorphous polymer. The information obtained at the chain network level was then used to provide qualitative information for the development of a material model at the macroscopic scale. In the second part, a more recent thermomechanical model will be presented. The model is based on the hyperelastic model of Edwards Vilgis modified to account for the mobility of polymer chains such as the evolution of the microstructure associated with the disentanglement of polymer chains.