Abstract

Hysteretic sorption and desorption of water is observed from 0 to 95% relative humidity and 298–333 K on a glassy polyurethane foam. It is postulated that sorption-induced swelling of the glassy polyurethane increases the concentration of accessible hydrogen-bonding adsorption sites for water. The accessibility of sites is kinetically controlled due to the restricted thermal motions of chains in the glassy polymer, causing a difference in accessible site concentrations during sorption and desorption. This discrepancy leads to hysteresis in the sorbed concentrations of water. A coupled chemo-mechanical model relating volumetric strain, adsorption site concentration, and sorbed water concentration is employed to describe water sorption hysteresis in the glassy polyurethane. This model not only describes the final mass uptake for each relative humidity step, but also captures the dynamics of water uptake, which exhibit diffusion and relaxation rate-controlled regimes.

Details

Title
A chemo-mechanical model for describing sorption hysteresis in a glassy polyurethane
Author
Foley, Brandon L. 1 ; Matt, Sarah M. 1 ; Castonguay, Stephen T. 1 ; Sun, Yunwei 1 ; Roy, Pratanu 1 ; Glascoe, Elizabeth A. 1 ; Sharma, Hom N. 2 

 Lawrence Livermore National Laboratory, Livermore, USA (GRID:grid.250008.f) (ISNI:0000 0001 2160 9702) 
 Lawrence Livermore National Laboratory, Livermore, USA (GRID:grid.250008.f) (ISNI:0000 0001 2160 9702); National Personal Protective Technology Laboratory (NPPTL), U.S. Centers for Disease Control and Prevention (CDC), National Institute for Occupational Safety and Health (NIOSH), Pittsburgh, USA (GRID:grid.416809.2) (ISNI:0000 0004 0423 0663) 
Pages
5640
Publication year
2024
Publication date
2024
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2941976834
Copyright
© The Author(s) 2024. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.