Role of viscoelasticity in predicting the shape memory effect of polymers

Torsional tests are used to study the shape memory property of an amorphous thermoset epoxy. The effect of the thermal history on the shape recovery is emphasized since most existing models are unable to reproduce the effect of the heating rate without using adjusted parameters. Here, the shape memory effect is modeled based only on the polymer viscoelasticity and its time-temperature superposition. The model parameters are solely determined from testing the material in dynamic mechanical analysis (DMA) and uniaxial tension at high temperatures. The parameters are easily introduced in a standard finite element code (ABAQUS) to accurately and precisely simulate and predict the shape memory behavior of the material submitted to various heating history. The simulation work highlights the crucial need for accurate temperature measurements in order to precisely predict the shape recovery of such a material.