SIMULATION OF THERMOMECHANICAL PROCESSES IN CRYSTALLIZING POLYMER

Constitutive equations are developed to describe the interrelation bet ween thermomechanical behavior and phase transitions in crystallizing polymers. A crystallizing polymer is considered as a two-component mix ture of amorphous and crystalline structures, the fraction of which is defined by the degree of crystallinity. Numerical realization is perf ormed using a variational method and a finite element procedure. The k ey feature of the calculation algorithm is reduction of a nonstationar y problem to a sequence of stationary problems on a nonuniform time me sh. The validity of the proposed mathematical model is supported by th e results of experiments performed to study the evolution of the stres s-strain state for a disk-shaped polyamide 6 plate on crystallization.