University of Oulu

Lakovaara, M., Sirviö, J.A., Ismail, M.Y. et al. Hydrophobic modification of nanocellulose and all-cellulose composite films using deep eutectic solvent as a reaction medium. Cellulose 28, 5433–5447 (2021).

Hydrophobic modification of nanocellulose and all-cellulose composite films using deep eutectic solvent as a reaction medium

Saved in:
Author: Lakovaara, Matias1; Sirviö, Juho Antti1; Ismail, Mostafa Y.1;
Organizations: 1Fibre and Particle Engineering Research Unit, University of Oulu, Oulu, Finland
2Optoelectronics and Measurement Techniques Unit, University of Oulu, Oulu, Finland
Format: article
Version: published version
Access: open
Online Access: PDF Full Text (PDF, 2.1 MB)
Persistent link:
Language: English
Published: Springer Nature, 2021
Publish Date: 2021-06-30


In this work, deep eutectic solvent (DES) based on imidazole and triethylmethylammonium chloride was used as a reaction medium for the esterification of cellulose nanofiber (CNF) and all-cellulose composite (ACC) films with n-octylsuccinic anhydride (OSA) to obtain high strength and sustainable films with increased hydrophobicity. Diffuse reflectance infrared Fourier transform spectroscopy and X-ray photoelectron spectroscopy were used to prove the success of the modification. The mechanical strength of the modified films was analyzed in dry, humid, and wet conditions, and the hydrophobicity of the films was indicated in terms of contact angle measurements. In addition, water absorption and transparency of the films were characterized. The modification was proven to be simple and fast, and mild conditions of 80 °C reaction temperature and 1 h reaction time were used. DES/OSA- modified CNF film exhibited better mechanical properties in dry, humid, and wet conditions compared to reference CNF film, and DES/OSA-modified ACC film displayed notable higher mechanical properties in wet state compared to that of reference CNF film (31 MPa tensile strength and 6.1% strain at break vs. 18 MPa and 2.2%, respectively). These improvements were partly attributed to higher contact angles of modified films (ACC-DES/OSA 60° and CNF-DES/OSA 51°) compared to CNF film (37°).

see all

Series: Cellulose
ISSN: 0969-0239
ISSN-E: 1572-882X
ISSN-L: 0969-0239
Volume: 28
Issue: 9
Pages: 5433 - 5447
DOI: 10.1007/s10570-021-03863-1
Type of Publication: A1 Journal article – refereed
Field of Science: 116 Chemical sciences
1182 Biochemistry, cell and molecular biology
216 Materials engineering
Funding: Open access funding provided by University of Oulu including Oulu University Hospital. The research was supported by the Academy of Finland project “ACNF” (325276).
Academy of Finland Grant Number: 325276
Detailed Information: 325276 (Academy of Finland Funding decision)
Copyright information: © The Author(s) 2021. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit