Predicting Catastrophic Failure of Semi-Crystalline Polymer Products

Catastrophic failure of polymers after prolonged exposure to load (for instance supporting structures, high-pressure pipes), limits their ultimate useful lifetime. Hence, understanding of that process, and, ideally, being able to accurately predict when and under which circumstances this phenomenon occurs is of critical importance, not only for the selection of the materials employed in such objects, but also for their optimal design for safe use. This issue is especially complex in the case of semi-crystalline polymers, which are heterogeneous systems comprised of an amorphous matrix with highly anisotropic crystallites of a size and orientation that are extremely dependent on the molecular weight distribution of the polymer and the conditions under which the material is processed. As a consequence, these structural features, and the associated mechanical properties, generally exhibit strong variations throughout even a single processed object. In the proposed research, we aim to develop a predictive, quantitative methodology that will enable not only evaluation of this process-induced structure development, but also provide direct assessment of its influence on the resulting short and long-term mechanical performance of the final product.