Valence can control the nonexponential viscoelastic relaxation of multivalent reversible gels

• DOI: 10.48550/arxiv.2112.07454
• Publication Date: 2021-01-01
• Authors: Hugo Le Roy; Jake Song; Gareth H. McKinley; Niels Holten‐Ande...; Martin Lenz
• Keywords: Stress relaxation

Gels made of telechelic polymers connected by reversible crosslinkers are a versatile design platform for biocompatible viscoelastic materials. Their linear response to step strain displays fast, near-exponential relaxation when using low valence crosslinkers, while larger supramolecular bring about much slower dynamics involving wide distribution time scales whose physical origin is still debated. Here, we propose model where the polymer gels in dilute regime originates from elementary events which bonds connecting two neighboring all disconnect. Larger allow greater average number them, but also generate more heterogeneity. We characterize resulting analytically, and accurately reproduce stress measurements on metal-coordinated hydrogels with variety crosslinker sizes including ions, metal-organic cages, nanoparticles. Our approach simple enough be extended any size could thus harnessed rational complex