Transient mechanics of slide-ring networks: A continuum model

Abstract Slide ring gels, developed from molecularly threaded polymer chains, have been getting increased attention for their unique modes of relaxation and toughness in the past ten years. While the methods of synthesis have become more sophisticated and efficient, theory has not kept up with experiments, and there exist many unexplained observations. In this paper, we develop a continuum-level model for slide ring gels based on thermodynamically consistent equations. We begin at the level of a single chain and perform statistical averaging to capture the unique molecular dynamics shown by polyrotaxane, the backbone chain of the network. We discover a unique dependence of relaxation on both level of strain and speed of deformation. We explain these properties quantitatively by assigning internal state variables that represent chain reptation and relative degree of chain-stretch and solve for their evolution during deformation.