Non-affine mechanics of entangled networks inspired by intermediate filaments

TL;DR

This paper investigates the mechanics of entangled filament networks inspired by intermediate filaments, revealing how they respond non-affinely to stretch and self-organize into optimal configurations, with implications for soft material design.

Contribution

It introduces an entanglement metric and a model linking cellular geometry to filament mechanics, advancing understanding of non-affine responses in filament networks.

Findings

Networks respond non-affinely beyond a threshold entanglement

Self-organization into star-shaped configurations under stretch

Framework for harnessing entanglement in soft materials

Abstract

Inspired by massive intermediate filament (IF) reorganization in superstretched epithelia, we examine computationally the principles controlling the mechanics of a set of entangled filaments whose ends slide on the cell boundary. We identify an entanglement metric and threshold beyond which random loose networks respond non-affinely and nonlinearly to stretch by self-organizing into structurally optimal star-shaped configurations. A simple model connecting cellular and filament strains links emergent mechanics to cell geometry, network topology, and filament mechanics. We identify a safety net mechanism in IF networks and provide a framework to harness entanglement in soft fibrous materials.