1. Description of the mechanical behavior of solid polymers

The microstructure of solid polymers is highly complex, which explains the complexity of their mechanical behavior (rheology). They are made up of macromolecules that interact via van der Waals forces. They can be totally amorphous or semi-crystalline. Their change-of-state temperatures, the glass transition temperature T _g for the amorphous phase, melting temperature T _F of the crystalline phase, may be below or above room temperature. These facts explain the complexity of their rheological characteristics. However, it is possible to propose a quantitative description