Drying stresses in cellulose nanocrystal coatings: Impact of molecular and macromolecular additives.

Autor: Klockars KW; Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, FI-00076 Aalto, Finland., Greca LG; Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, FI-00076 Aalto, Finland., Majoinen J; Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, FI-00076 Aalto, Finland., Mihhels K; Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, FI-00076 Aalto, Finland., Rojas OJ; Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, FI-00076 Aalto, Finland; Bioproducts Institute, Department of Chemical and Biological Engineering, Department of Chemistry and Department of Wood Science, University of British Columbia, 2360 East Mall, Vancouver, BC V6T 1Z4, Canada. Electronic address: orlando.rojas@ubc.ca., Tardy BL; Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, FI-00076 Aalto, Finland; Department of Chemical Engineering, Khalifa University, Abu Dhabi, United Arab Emirates. Electronic address: blaise.tardy@ku.ac.ae.
Jazyk: angličtina
Zdroj: Carbohydrate polymers [Carbohydr Polym] 2023 Mar 01; Vol. 303, pp. 120465. Date of Electronic Publication: 2022 Dec 15.
DOI: 10.1016/j.carbpol.2022.120465
Abstrakt: The industrial implementation of cellulose nanocrystals (CNCs) in films and coatings requires thorough evaluation of the internal stresses post-consolidation, as they cause fracturing and peeling. Characterizing the impact of plasticizing additives on stress is therefore critical. Herein, we use the deflection of thin glass substrates to measure drying stresses in consolidating CNC films, and benchmark the impact of five additives (glucose, glycerol, poly(ethylene glycol) (PEG), poly(vinyl alcohol) (PVA) and bovine serum albumin). Glycerol and PEG reduced drying stresses effectively, while PEG of increased molecular weight (from 0.2 to 10 kDa), PVA, and BSA were less effective. We analyzed the temporal aspects of the process, where stress relaxation of up to 30 % was observed 2 years after coating formation. Finally, we provide a framework to evaluate the impact of CNC morphology on residual stresses. The introduced approach is expected to fast-track the optimization and implementation of coatings based on biocolloids.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)
Databáze: MEDLINE
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