Predicting failure locations in model end-linked polymer networks

TL;DR

This study combines molecular dynamics simulations and network analysis to predict failure points in end-linked polymer networks, revealing key structural and topological factors influencing fracture locations.

Contribution

It introduces a novel approach integrating GEBC and strand orientation analysis to accurately predict failure sites in polymer networks.

Findings

Polymer strands with fewer defects are less likely to break.

Higher GEBC values correlate with increased failure risk.

Strands aligned with deformation are more prone to fracture.

Abstract

The fracture of end-linked polymer networks and gels has a significant impact on the performance of these versatile and widely used materials, and a molecular-level understanding of the fracture process is crucial for the design of new materials. Network analysis techniques, especially geodesic edge betweenness centrality (GEBC) have been proven effective in failure locations across various network materials. In this work, we employ a combination of coarse-grained molecular dynamics simulations and network analysis techniques to investigate the effectiveness of GEBC and polymer strand orientation in predicting failure locations in model end-linked polymer networks. We demonstrate that polymer strands with fewer topological defects in their local surroundings, higher GEBC values compared to the system average, and greater alignment to the deformation axis are more prone to breaking under the uniaxial tensile deformation. Our results can be used to further refine the description of the processes at play during the failure of polymer networks and provide valuable insights into the inverse design of network materials with desired fracture properties.