Nonaffine motion and network reorganization in entangled polymer networks.

Abstract

This paper presents a computational model designed to capture the mechanical behavior of entangled polymer networks, described by dynamic and slideable cross-linking junctions. The model adopts a network-level approach, where the polymer chains between junctions are represented by segments exhibiting entropic elasticity, and the sliding of chains through entanglements is governed by a frictional law. Additionally, the model incorporates stochastic processes for the creation and depletion of entanglement junctions, dynamically coupled with sliding mechanics. This framework enables the exploration of the time-dependent mechanical response of entangled polymers with and without covalent cross-links. We apply this model to study the nonlinear rheology of such networks, linking macroscopic stress-strain behavior to the underlying microscopic events within the network. The approach is computationally efficient, making it a useful tool for understanding how network design influences polymer performance in elasticity, rheology, and general mechanical features. This work provides valuable insights into the relationship between molecular-level interactions and the macroscopic properties of entangled polymer systems, with potential applications in the design and optimization of advanced polymer materials.