Introduction With the rapid development of renewable resources and green and environmentally friendly materials, nanocellulose (Nanocellulose) has gradually become a hot topic in scientific research and industrial fields due to its advantages such as lightweight, high strength, renewable and degradable. Among them, TEMPO oxidation modification, as an efficient and controllable surface functionalization method, gives nanocellulose more performance and application potential. This article will introduce the principles, characteristics and typical applications of TEMPO oxidized nanocellulose from a popular science perspective. What is TEMPO oxidation? TEMPO (2,2,6,6-tetramethylpiperidin-1-oxygen radical) is an organic radical catalyst. Under basic conditions, TEMPO works together with sodium hypochlorite (NaClO) and sodium bromide (NaBr) to selectively oxidize the primary hydroxyl group at the C6 position of cellulose molecule to carboxyl (–COOH). This reaction has the following advantages: strong selectivity: mainly

Abstract Carboxylated modified Nanocellulose (CNCF) is a functional nanomaterial that introduces carboxylated (–COOH) groups on the cellulose surface by chemical modification. This material has the high strength, high specific surface area and good dispersion of nanocellulose, and imparts better hydrophilicity, reactive activity and interface binding ability under the action of surface carboxyl groups. This article will introduce the preparation methods, key properties, typical application fields and future development trends of carboxylated modified nanocellulose, and provide reference for scientific researchers and related companies. Introduction to carboxylated modified nanocellulose Nanocellulose is a renewable green material derived from natural cellulose, with advantages such as high crystallinity, lightweight, and high strength, and degradability. However, the original nanocellulose has problems such as single surface functional groups, insufficient dispersion, and limited compatibility with other materials. Modification by carboxylation

1. Introduction Nanocellulose (NC) is a green nanomaterial derived from natural cellulose, with high specific surface area, high crystallinity, excellent mechanical properties and renewability. However, natural nanocellulose surfaces are rich in hydroxyl groups and exhibit strong hydrophilicity, which limits its application in non-polar polymers, oily systems and hydrophobic substrates. To this end, scientific researchers and enterprises have transformed their surface into hydrophobic nanocellulose through chemical modification or physical treatment, greatly expanding their application space. Keywords: nanocellulose, hydrophobic modification, esterification, silanization, oil-water separation, composite materials 2. Preparation process of hydrophobic nanocellulose, typical reactants/means, advantages and disadvantages of esterification reaction, fatty acid anhydride, stearic anhydride, isocyanate process mature, significant part of the hydrophobic reaction requires organic solvent silanization to modify triethoxyoctylsilane and methyl trichlorosilane hydrophobic long-lasting, suitable for