ON THE PHYSICS REQUIRED FOR PREDICTION OF LONG-TERM PERFORMANCE OF POLYMERS AND THEIR COMPOSITES

The long term performance of polymers and their composites is an impor tant aspect of their increasing use in engineering applications. Tempo ral, thermal, and mechanical stresses can all contribute to the deteri oration of performance. Here we examine the concepts of the physics of glassy polymers and how they are important in developing constitutive equations that describe their volume/temperature/stress time response . The understanding of such response forms the basis of the prediction of long term performance.