Deformation of hydrogel during freezing

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Séguy, Lila, Huerre, Axel, Protière, Suzie
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866929533748248576
author Séguy, Lila
Huerre, Axel
Protière, Suzie
author_facet Séguy, Lila
Huerre, Axel
Protière, Suzie
contents We conducted experiments to directionally freeze agar hydrogel drops with different polymer concentrations, on a copper substrate maintained at low temperature. Unlike the water droplet studied in the literature, where the liquid part can reorganize during freezing, our droplets show a distinct deformation. This is due to the presence of the viscoelastic solid polymer matrix, which prevents deformation of the unfrozen part, leading mainly to elongation in the direction of the temperature gradient. We then derive a model describing this deformation. It assumes a flat freezing front, a change in volume at the front resulting from the Stefan condition, and a remaining volume to be frozen identical in shape to the initial one. The latter is in good agreement with experimental observations as long as water fluxes in the porous hydrogel remain negligible. It is also conclusive for different object shapes, as the hydrogel can be freely molded without a container.
format Preprint
id arxiv_https___arxiv_org_abs_2410_06766
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Deformation of hydrogel during freezing
Séguy, Lila
Huerre, Axel
Protière, Suzie
Soft Condensed Matter
Fluid Dynamics
We conducted experiments to directionally freeze agar hydrogel drops with different polymer concentrations, on a copper substrate maintained at low temperature. Unlike the water droplet studied in the literature, where the liquid part can reorganize during freezing, our droplets show a distinct deformation. This is due to the presence of the viscoelastic solid polymer matrix, which prevents deformation of the unfrozen part, leading mainly to elongation in the direction of the temperature gradient. We then derive a model describing this deformation. It assumes a flat freezing front, a change in volume at the front resulting from the Stefan condition, and a remaining volume to be frozen identical in shape to the initial one. The latter is in good agreement with experimental observations as long as water fluxes in the porous hydrogel remain negligible. It is also conclusive for different object shapes, as the hydrogel can be freely molded without a container.
title Deformation of hydrogel during freezing
topic Soft Condensed Matter
Fluid Dynamics
url https://arxiv.org/abs/2410.06766