Options
DEM-based approach for the modeling of gelation and its application to alginate
Citation Link: https://doi.org/10.15480/882.4159
Publikationstyp
Journal Article
Date Issued
2022-01-10
Sprache
English
Author(s)
Depta, Philipp Nicolas
TORE-DOI
Volume
62
Issue
1
Start Page
49
End Page
70
Citation
Journal of Chemical Information and Modeling 62 (1): 49-70 (2022-01-10)
Publisher DOI
Scopus ID
Publisher
American Chemical Society
Peer Reviewed
true
The gelation of biopolymers is of great interest in the material science community and has gained increasing relevance in the past few decades, especially in the context of aerogels lightweight open nanoporous materials. Understanding the underlying gel structure and influence of process parameters is of great importance to predict material properties such as mechanical strength. In order to improve understanding of the gelation mechanism in aqueous solution, this work presents a novel approach based on the discrete element method for the mesoscale for modeling gelation of hydrogels, similarly to an extremely coarse-grained molecular dynamics (MD) approach. For this, polymer chains are abstracted as dimer units connected by flexible bonds and interactions between units and with the environment, that is, diffusion in implicit water, are described. The model is based on Langevin dynamics and includes an implicit probabilistic ion model to capture the effects of ion availability during ion-mediated gelation. The model components are fully derived and parameterized using literature data and theoretical considerations based on a simplified representation of atomistic processes. The presented model enables investigations of the higher-scale network formation during gelation on the micrometer and millisecond scale, which are beyond classical modeling approaches such as MD. As a model system, calcium-mediated alginate gelation is investigated including the influence of ion concentration, polymer composition, polymer concentration, and molecular weight. The model is verified against numerous literature data as well as own experimental results for the corresponding Ca-alginate hydrogels using nitrogen porosimetry, NMR cryoporometry, and small-angle neutron scattering. The model reproduces both bundle size and pore size distribution in a reasonable agreement with the experiments. Overall, the modeling approach paves the way to physically motivated design of alginate gels.
Subjects
Multiscale modeling
Gelation
Alginate
Langevin dynamics
DDC Class
540: Chemie
Funding(s)
More Funding Information
The NMR measurements have been financially supported by the National Research, Development and Innovation Office, Hungarian Science Foundation (OTKA: FK_17-124 571).
Publication version
publishedVersion
Loading...
Name
acs.jcim.1c01076.pdf
Size
10.04 MB
Format
Adobe PDF