Takeshita, S, Sadeghpour, A orcid.org/0000-0002-0475-7858, Malfait, WJ et al. (3 more authors) (2019) Formation of Nanofibrous Structure in Biopolymer Aerogel during Supercritical CO2 Processing: The Case of Chitosan Aerogel. Biomacromolecules, 20 (5). pp. 2051-2057. ISSN 1525-7797
Abstract
Supercritical drying is widely considered as the gold standard to produce aerogels that preserve the microstructure of the gels, but we have found this is not always the case. Chitosan aerogel, one of the emerging biopolymer aerogels, was prepared by chemical cross-linking gelation, followed by solvent exchange with methanol and supercritical drying using CO2. Small-angle X-ray scattering analysis shows that the structure of the wet gel, which consists of Gaussian chains of individual molecular strands, converts into a nanofibrous network during CO2 processing. In situ observation reveals a drastic shrinkage of the gel in CO2, demonstrating that physical coagulation caused by the low affinity between chitosan and CO2 is the main structure-forming step. These results challenge the common perception of supercritical drying: it is no longer an inactive drying method, but rather an active nanostructure forming a tool to produce porous biopolymer materials with tailored structure and properties.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2019 American Chemical Society. This is an author produced version of an article published in Biomacromolecules. Uploaded in accordance with the publisher's self-archiving policy. |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > School of Food Science and Nutrition (Leeds) > FSN Chemistry and Biochemistry (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 03 Sep 2021 11:28 |
Last Modified: | 25 Jun 2023 22:45 |
Status: | Published |
Publisher: | American Chemical Society |
Identification Number: | 10.1021/acs.biomac.9b00246 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:177776 |