Principles of structural-mechanical modeling of polymers and composites

A general approach to the description of the mechanical properties of materials whose deformation is accompanied by considerable structural rearrangements is developed. As in the case of classical simulation of the deformation behavior of viscoelastic and elastoplastic bodies, the concept of basic structural-mechanical element that reflects the properties of a fragment of a continuous medium is introduced. The simplest version of two alternative structural states is considered. Equations that define the kinetics of transition between these states and the mechanical properties of the base structural-mechanical element include expressions for elastic strain, plastic flow, and structure evolution. It is assumed that structural transitions and plastic flow are effected by the thermofluctuation mechanism. It is shown that the array of elements characterized by an appropriate set of parameters can describe the specific features of deformation behavior and structure evolution for a wide range of materials, in particular, polymers and composites, at their early deformation stages.