Preparation of nanocellulose from cotton fibers in deep eutectic solvent (DES) and its application in paper

Abstract

The bond strength and stability of the intermolecular network structure of cellulose play a decisive role in the tensile strength and rupture resistance of paper. In this work, the surface morphology, the chemical composition, and the crystal structure of nanocellulose prepared from cotton fibers were characterized by scanning electron microscopy (SEM) analysis, X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) to prepare cotton fiber nanocellulose by green solvent deep-eutectic solvent pretreatment combined with the ultrasonic method. Nanocellulose of different morphology and structure was used as a papermaking additive to explore its effect on the strength performance of the paper. The results show that the burst resistance index of the paper handsheets could be increased by 6.1% and 9.8%. The burst resistance index improved as the added amount of the NFC was increased.

A ternary eutectic solvent for cellulose nanocrystal production: exploring the recyclability and pre-pilot scale-up

“…Recyclable extraction media using acidic NADES have been efficient in providing CNC and cellulose nanofibers (CNF) by selective hydrolysis of amorphous cellulose (Bjelic et al, 2022). Large volumes of NADES have been used to obtain CNC/CNF by simple stirring and heating of its organic components assisted by ultrasound; among them, those that stand out are choline chloride: oxalic acid dihydrate (Sirviö et al, 2016;Yu et al, 2020;Douard et al, 2021), choline chloride: urea, choline chloride: glycerol (Lim et al, 2022), betaine: oxalic acid dihydrate (Deng et al, 2022), choline chloride: formic acid (Wu et al, 2021), choline chloride: pTSA, choline chloride: levulinic acid (Sirviö et al, 2016), and choline chloride: lactic acid (Liu et al, 2019). The synthesis of CNC using binary eutectic mixtures usually requires reaction times of 3-6 h at temperatures between 60 °C and 120 °C and ultrasound treatment of 20-30 min.…”