Time is length in self-similar logarithmic aging of physically cross-linked semiflexible polymer networks

Abstract

Physical aging in polymers is a fundamental yet poorly understood phenomenon, as diverse macromolecular systems exhibit remarkably similar slow dynamics. Through molecular dynamics simulations of physically crosslinked networks composed of semiflexible polymers, we identify a previously unexplored class of self-similar aging. The network undergoes ultra-slow coarsening characterized by a logarithmically growing mesh size, $L(t)\sim \ln t$, which governs the spatial organization, cohesive and bending energies, and the aging dynamics of the system. This single time-dependent length scale defines an internal clock, giving rise to spatio- temporal self-similarity of both structure and dynamics - offering a perspective on aging in soft and disordered materials.