Transient instabilities in swelling dynamics

TL;DR

This paper presents a detailed computational study of swelling dynamics in hydrogel spheres, focusing on transient behaviors and surface instabilities during solvent absorption.

Contribution

It introduces an accurate computational model to analyze the onset of surface instabilities in swelling hydrogels, highlighting the role of material parameters.

Findings

Identification of transient instability onset during swelling

Correlation between material parameters and surface pattern formation

Quantitative measures of surface roughness during swelling

Abstract

We investigate the swelling dynamics driven by solvent absorption in a hydrogel sphere immersed in a solvent bath, through an accurate computational model and numerical study. We extensively describe the transient process from dry to wet and discuss the onset of surface instabilities through a measure of the lack of smoothness of the outer surface and a morphological pattern of that surface with respect to the two material parameters driving the swelling dynamics.