ChemRxiv
These are preliminary reports that have not been peer-reviewed. They should not be regarded as conclusive, guide clinical practice/health-related behavior, or be reported in news media as established information. For more information, please see our FAQs.
HydrophobicCNF_final.pdf (2.88 MB)

Regioselective and Water-Promoted Surface Esterification of Never-Dried Cellulose Fibers Towards Nanofibers with Adjustable Surface Energy

preprint
submitted on 12.04.2021, 12:11 and posted on 13.04.2021, 12:51 by Marco Beaumont, Caio G. Otoni, Bruno D. Mattos, Tetyana V. Koso, Roozbeh Abidnejad, Bin Zhao, Anett Kondor, Alistair W. T. King, Orlando J. Rojas
A new regioselective route is introduced for surface modification of biological colloids in the presence of water. Taking the case of cellulose nanofibers (CNFs), we demonstrate a site-specific (93% selective) reaction between the primary surface hydroxyl groups (C6-OH) of cellulose and acyl imidazoles. CNFs bearing C6-acetyl and C6-iso-butyl groups, with a degree of substitution up to 1 mmol·g–1 were yielded upon surface esterification, affording nanofibers of adjustable surface energy. The morphological and structural features of the nanofibers remained largely unaffected, but the regioselective surface reactions enabled tailoring of interfacial interactions, as demonstrated in oil/water Pickering emulsions. Our method precludes the need for drying or solvent exchange to organic solvents for surface esterifications, which are otherwise demanded in the fabrication of esterified colloids and polysaccharides and can be potentially implemented into reactive extrusion and compounding of high-solid content colloids. The proposed acylation is expected to open new and sustainable approaches that benefit from the presence of water and the high selectivity.

History

Email Address of Submitting Author

marcobeaumont1@gmail.com

Institution

University of Natural Resources and Life Sciences, Vienna

Country

Austria

ORCID For Submitting Author

0000-0002-2571-497X

Declaration of Conflict of Interest

No conflict of interest.

Exports

ChemRxiv

Exports