materials Review From Cellulose to Cellulose Nanofibrils—A Comprehensive Review of the Preparation and Modification of Cellulose Nanofibrils 1, 1, 1 1 1,2, 1,2 1 Tan Yi y, Hanyu Zhao y, Qi Mo , Donglei Pan , Yang Liu *, Lijie Huang , Hao Xu , Bao Hu 1 and Hainong Song 3 1 College of Light Industry and Food Engineering, Guangxi University, Junwu Rd, Xixiangtang District, Nanning 530004, China;
[email protected] (T.Y.);
[email protected] (H.Z.);
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[email protected] (L.H.);
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[email protected] (B.H.) 2 Guangxi Key Laboratory of Clean Pulp & Papermaking and Pollution Control, Junwu Rd, Xixiangtang District, Nanning 530004, China 3 Guangxi Bossco Environmental Protection Technology Co., Ltd., 12 Kexing Road, High-tech Zone, Nanning 530012, China;
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[email protected]; Tel.: +86-155-7832-3385 Co-first author. y Received: 24 September 2020; Accepted: 30 October 2020; Published: 10 November 2020 Abstract: This review summarizes the preparation methods of cellulose nanofibrils (CNFs) and the progress in the research pertaining to their surface modification. Moreover, the preparation and surface modification of nanocellulose were comprehensively introduced based on the existing literature. The review focuses on the mechanical treatment of cellulose, the surface modification of fibrillated fibers during pretreatment, the surface modification of nanocellulose and the modification of CNFs and their functional application. In the past five years, research on cellulose nanofibrils has progressed with developments in nanomaterials research technology.