• Lourençon, Tainise
• Pääkkönen, Timo
• Guccini, Valentina
• Penttilä, Paavo A.
• Rautkari, Lauri
• Kontturi, Eero
• Altgen, Michael

Abstract

Funding Information: The authors thank Dr. Chic-Wei Lin for additional experimental work, Hanna Seppäläinen for the chemical composition analysis, and Dr. Leena Pitkänen for her help with the GPC analysis. The authors also acknowledge the OtaNano─Nanomicroscopy Center (Aalto-NMC) for the provision of facilities and technical support offered for the WAXS and SEM measurements. This work made use of Aalto University Bioeconomy Facilities. P.P. acknowledges financial support by the Academy of Finland (grant no. 315768). T.P. acknowledges the funding from Business Finland (R2B project: Gas-driven technology for cost-efficient production of cellulose nanocrystals 42472/31/2020). Publisher Copyright: © ; The HCl gas system previously used to produce cellulose nanocrystals was applied on Scots pine wood, aiming at a controlled deconstruction of its macrostructure while understanding the effect on its microstructure. The HCl gas treatments resulted in a well-preserved cellular structure of the wood. Differences in wood initial moisture content (iMC) prior to HCl gas treatment played a key role in hydrolysis rather than the studied range of exposure time to the acidic gas. Higher iMCs were correlated with a higher degradation of hemicellulose, while crystalline cellulose microfibrils were not largely affected by the treatments. Remarkably, the hydrogen-deuterium exchange technique showed an increase in accessible OH group concentration at higher iMCs, despite the additional loss in hemicelluloses. Unrelated to changes in the accessible OH group concentration, the HCl gas treatment reduced the concentration of absorbed D2O molecules. ; Peer reviewed

Topics

• microstructure
• polymer
• scanning electron microscopy
• Hydrogen
• chemical composition
• wood
• cellulose