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arXiv · 2606.07384

Hydrogel mechanics below swelling equilibrium

A. Chao Correas·Y. Feng·R. W. Style·D. S. Kammer
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Abstract

Hydrogels are versatile materials due to their softness and ability to undergo large changes in water content. Their mechanics, however, are complex, being a tight coupling between fluid flow and elastic deformations. We use experiments and theory to show that this coupling simplifies when hydrogels are not fully swollen. In this regime, polymer-water affinity controls local hydration, while the much weaker polymer network elasticity plays a secondary role, setting the resulting elastic shape. This observation enables a simplified model that accurately predicts stresses and deformations.

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A. Chao Correas, Y. Feng, R. W. Style, D. S. Kammer. 2026-06-05. Hydrogel mechanics below swelling equilibrium. https://arxiv.org/abs/2606.07384

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