TY - JOUR
T1 - Delignification and Ionic Liquid Treatment of Wood toward Multifunctional High-Performance Structural Materials
AU - Khakalo, Alexey
AU - Tanaka, Atsushi
AU - Korpela, Antti
AU - Orelma, Hannes
N1 - Funding Information:
This study was carried out in the CellFi (conversion of cellulose to plastic) project funded by Business Finland together with Finnish industrial companies (Stora Enso Ltd, Metsä Board Ltd, Metsä Fibre Ltd, Pölkky Ltd, FL Pipe Ltd, and Versoul Ltd). Vuokko Liukkonen and Hille Rautkoski are thanked for performing grease, water vapor, and oxygen permeability measurements. Professor Ilkka Kilpeläinen (University of Helsinki) is thanked for his active participation in the CellFi project. Kimmo Velling is acknowledged for performing the cross-sectional preparations for SEM imaging. The work was part of the Academy of Finland Flagship Programme under project nos. 318890 and 318891 (Competence Center for Materials Bioeconomy, FinnCERES).
Publisher Copyright:
© 2020 American Chemical Society.
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2020/5/20
Y1 - 2020/5/20
N2 - Wood-based multifunctional materials with excellent mechanical performance are increasingly considered for sustainable advanced applications due to their unique hierarchical structure and inherent reinforcing cellulose phase orientation. Nonetheless, a wider multipurpose utilization of wood materials is so far hampered because of constraints arising from scalable functionalization, efficient processing, facile shaping as well asnatural heterogeneity and durability. This study introduces a multifunctional all-wood material fabrication method relying on delignification, ionic liquid (IL) treatment, and pressure-assisted consolidation of wood. Structure-retaining controlled delignification of wood was performed to enable direct access to the hierarchical cellulose assembly, while preserving the highly aligned and thus beneficial wood structural directionality. As a following step, the obtained biobased scaffold with an increased porosity was infiltrated with an IL and heat-activated to partially dissolve and soften the cellulose fiber surface. Samples washed with water to remove IL exhibited pronounced isotropic flexibility, which upon combined compression and lateral shear allowed the fabrication of various 3D shapes with adjustable fiber architecture. The obtained very compact and totally additive-free all-wood materials were extensively characterized, revealing superior mechanical performance, and gained multifunctionality compared to native wood.
AB - Wood-based multifunctional materials with excellent mechanical performance are increasingly considered for sustainable advanced applications due to their unique hierarchical structure and inherent reinforcing cellulose phase orientation. Nonetheless, a wider multipurpose utilization of wood materials is so far hampered because of constraints arising from scalable functionalization, efficient processing, facile shaping as well asnatural heterogeneity and durability. This study introduces a multifunctional all-wood material fabrication method relying on delignification, ionic liquid (IL) treatment, and pressure-assisted consolidation of wood. Structure-retaining controlled delignification of wood was performed to enable direct access to the hierarchical cellulose assembly, while preserving the highly aligned and thus beneficial wood structural directionality. As a following step, the obtained biobased scaffold with an increased porosity was infiltrated with an IL and heat-activated to partially dissolve and soften the cellulose fiber surface. Samples washed with water to remove IL exhibited pronounced isotropic flexibility, which upon combined compression and lateral shear allowed the fabrication of various 3D shapes with adjustable fiber architecture. The obtained very compact and totally additive-free all-wood materials were extensively characterized, revealing superior mechanical performance, and gained multifunctionality compared to native wood.
KW - all-wood materials
KW - delignification
KW - ionic liquid dissolution
KW - natural fiber interpenetrating composites
KW - wet 3D shaping
KW - wood modification
UR - http://www.scopus.com/inward/record.url?scp=85084527750&partnerID=8YFLogxK
U2 - 10.1021/acsami.0c02221
DO - 10.1021/acsami.0c02221
M3 - Article
C2 - 32337962
AN - SCOPUS:85084527750
SN - 1944-8244
VL - 12
SP - 23532
EP - 23542
JO - ACS Applied Materials & Interfaces
JF - ACS Applied Materials & Interfaces
IS - 20
ER -