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Deep eutectic solvents (DES) have been regarded as green solvents in the biorefinery of lignocellulosic biomass, but long duration time has severely limited efficiency. The microwave-assisted DES pretreatment along with enzymatic hydrolysis and high-pressure homogenization process was proposed to produce lignin-containing cellulose nanofibrils (LCNF) from corncob. Benefiting from microwave-assisted DES pretreatment, the duration time was greatly shortened; meanwhile the effects of different kinds of DES on the resultant LCNF were investigated. The results showed that, the microwave-assisted DES fabricated LCNF (M-LCNF) was successfully obtained, exhibiting good nano size, thermal stability, colloidal stability, and fluorescence. M-LCNF was further introduced into phytic acid (PA) enhanced poly(acrylamide-co-acrylic acid) (P(AM-co-AA)) network and constructed composite conductive hydrogels (PLP). The obtained hydrogels exhibited good mechanical strength, UV blocking ability, fluorescence, and conductivity. A simple battery assembled with the resultant PLP as electrolyte had an out voltage of 2.41 V. The composite conductive hydrogel showed good sensing performance towards different stimuli (e.g., stretching and compression) and human motions in real time. It is expected that this research would provide an alternative way for green fabrication of LCNF and potential application of LCNF in flexible sensors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

As the promising anode material of lithium-ion batteries (LIBs), SiO 2 has high theoretical capacity, but the volume expansion severely hinders its application. To address the challenge, inspired by the highly flexible spider-web architecture, the SiO 2 @carbonized polyaniline/carbonized 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofibrils (SiO 2 @cPANI/cTOCNFs) composite was designed, and fabricated via carbonizing the freeze-dried SiO 2 @PANI/TOCNFs. The resultant SiO 2 @cPANI/cTOCNFs composite exhibited unique spider-web-like nanostructures, providing a double-layer carbon network to protect SiO 2 anode material. The results showed that, the SiO 2 @cPANI/cTOCNFs composite as anode material of LIBs offered a reversible capacity of 1103 mAh g -1 at a current density of 0.1 A g -1 after 200 cycles, and gave a capacity of 302 mAh g -1 after 1000 cycles at a current density of 1 A g -1 , exhibiting excellent cycling stability. This study provides a strategy of spider-web-inspired cellulose nanofibrils networking polyaniline-encapsulated silica nanoparticles as anode material of LIBs., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Lignocellulosic biomass-derived nanocellulose has been attracting more and more attentions due to its distinguished advantages and various applications, but its development has been restricted by the preparation especially with environmental friendly approach. Herein, lignin-containing cellulose nanofibrils (LCNF) was prepared from corncob via the combined pretreatment of choline chloride-based DES (ChCl-DES) and enzymatic hydrolysis followed by high-pressure homogenization. The effects of different types of ChCl-DES on the properties of LCNF were investigated and compared. The results showed that LCNF can be successfully fabricated through the combined pretreatments; the LCNF had an average diameter of 60-90 nm, exhibited good fluorescence, high thermal stability (up to 353 °C of T max ), hydrophobicity, stability, and redispersibility in organic solvent; AC-LCNF showed well oriented arrangement, the highest hydrophobicity and fluorescence, and distinguished redispersibility especially in DMSO. ChCl-DES as one green and sustainable approach would realize efficient separation and high value-added utilization of agricultural residues., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

An efficient and low-cost approach to preparing CNFs with succinic acid hydrolysis and NaClO 2 oxidation is explored. High-temperature-short-time hydrolysis can depolymerize the cellulose, whereas the dispersibility of the CNFs is hugely enhanced by NaClO 2 oxidation under alkaline condition. The degradation of cellulose in succinic acid hydrolysis follows first-order reaction kinetics and is severely influenced by the hydrolysis temperature, moreover, the molecular chains of the cellulose are seriously cracked under the optimized condition. The NaClO 2 oxidation greatly improves the zeta potential (-36.2 mV) and the dispersibility of the CNFs. The obtained CNFs have an ultimate yield of 94.6%, and the diameter distribution is mainly within 20-40 nm. In addition, some amount of carboxyl groups in the cellulose will be instead of the hydroxyl groups, and the crystallinity of the CNFs is significantly increased., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The laccase/TEMPO system was employed to oxidise the C6 primary hydroxyl group on the chitosan (CS) to form a carboxyl group to obtain oxidised chitosan (C-COS). The silver-oxidised chitosan complex(C-COS-Ag) was prepared by reacting C-COS with silver nitrate, then C-COS-Ag and cotton fibres were subjected to a reaction to prepare bacteriostatic fibres. FT-IR and XPS analysis showed that: Ag + and C-COS were combined in these forms: Ag, [Ag(NH 3 ) 2 ] OH, -COOAg, and Ag 2 O. C-COS-Ag was combined with cotton fibres by way of ester bonds. The inhibition zone of bacteriostatic fibres was all greater than 11 mm. After 50 washing tests, the bacteriostatic effect of bacteriostatic fibres remained at above 99 %. The amount of silver ions that had migrated from the bacteriostatic fibre was 3.336 mg/kg., (Copyright © 2021. Published by Elsevier Ltd.)

It is important to make full utilization of industrial biomass residues. Pulp was prepared from licorice residues by soda-anthraquinone pulping followed by peroxyacetic acid bleaching. Cellulose nanofibril was obtained by enzymatic pretreatment followed by homogenization of the pulp (ETCNF). The effects of enzymatic pretreatment on ETCNF were investigated. Chitosan nanofibril (CHN) and lignin nanoparticles (LNPs) were prepared and used for ETCNF composites, respectively. The results showed that ETCNF exhibited clear nanofibrillar structure and a highly relative colloidal stability, and a much higher crystallinity index and thermal stability compared to TEMPO-medicated oxidized one; the cellulose composite films incorporated with CHN or LNPs exhibited good thermal stability and hydrophobicity. Compared with ETCNF film, ETCNF@LNPs-5.0% film showed higher UV-blocking ability and thermal stability, but reduced light transmittance, while ETCNF@CHN-5.0% film showed improved mechanical properties and similar light transmittance. This study would expend licorice residues as potential materials for CNF and its applications., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Research on biodegradable cellulose composite film with unique properties is of significance to alleviate current dependency on petroleum-based polymers, and to promote highly efficient utilization of lignocellulosic biomass. Lignin nanoparticles (LNPs) have been considered as a promising material for high value-added products. In this study, LNPs were prepared from corncob lignin via anti-solvent precipitation method, and then characterized by FTIR, TGA, AFM, and NMR. The CNF@CLNPs composite film was fabricated by blending CLNPs with CNF. The results showed that the CLNPs had an average diameter of about 118 nm, meanwhile the main structures and properties of corncob lignin were maintained. The CNF@CLNPs composite film exhibited a high ultraviolet resistance, and a good antibacterial activity against both Escherichia coli and Staphylococcus aureus. It is expected that the CNF@CLNPs composite film would have potential applications in outdoor materials and food packaging., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

In this study, a strong and optically transparent nanopaper was fabricated from cellulose nanofibril (CNF) of corncob residues, an abundant byproduct from the processing of corncobs. Two processes were applied to successfully generate CNF from corncob residues. The resultant CNF mainly consists of fibers with diameter (height) of about 1.0 - 5.0 nm on average. The results showed that the as-prepared cellulose nanopaper (CNP) exhibited good strength, optical and thermal properties, with the tensile strength and tensile fracture strain of CNP being 65.3 MPa and 2.3%, respectively; the optical transmittance was close to 90% in the visible range; the highest degradation peak temperature was about 290 °C; the water contact angle at 30 s was 68.2°; A-CNP showed much higher optical properties and hydrophobicity, similar thermal ability, but slightly lower strength properties, compared with B-CNP. It can be seen that corncob residues are suitable choice of raw material for cellulose nanopaper, and is expected to find similar applications in flexible electronics and energy products as those of other raw materials used for this purpose., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Xylan is a part of hemicelluloses of woody materials and can be converted to value-added products such as flocculants for the textile industry. To assess the production of flocculants from hemicelluloses of woody materials, xylan was selected as a model and rendered cationic via copolymerization. In this study, the copolymerization reaction of xylan and [2-(methacryloyloxy) ethyl] trimethylammonium chloride (METAC) was optimized. The optimum parameters were 3mol/mol METAC/xylose, 3h reaction time, 80°C reaction temperature, pH 7 and 25g/L xylan concentration. The copolymer was characterized by a charge density analyzer, viscometer, gel permeation chromatography (GPC), light scattering instrument, Fourier transform infrared spectroscopy (FTIR) and an elemental analyzer. The application of the cationic xylan copolymer as a flocculant to decolorize the simulated reactive orange 16 azo-dye wastewater was evaluated. The results confirmed that, by having 160mg/L xylan-METAC concentration in the dye solution with the concentration of 100mg/L, 97.8% of dye could be removed., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Nanocrystalline cellulose (CNC) as a renewable/sustainable material, has received much attention. Herein we studied CNC as carriers for a hydrophobic spirooxazine (SO)-based dye, 1,3-dihydro-1,3,3-trimethylspiro[2H-indole-2,3'-[3H]naphtha[2,1-b][1,4]oxazine], which may have potential applications in reversible memory photo-devices, textiles, photo-sensitive paper coatings, and inkjet printing inks. Due to the high cost and water-insolubility of this dye, it is desirable to improve its coloration efficiency and water-dispersibility. The experimental approach was to use CNC as carriers for the SO dye, thus obtaining a stable photochromic dye in aqueous systems. Transmission electron microscope (TEM) observation confirmed that the SO dye adsorbed on the surface of the CNC, which functioned as carriers for the photochromic dye. An impregnation process was adopted to anchor the dye onto cellulosic paper. It was found that the use of CNC resulted in a significant improvement in the SO coloration efficiency. The color stability and fatigue resistance were also studied. The use of CNC as carriers for a hydrophobic compound, its enhancement of associated properties, and its subsequent application were demonstrated., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Spirooxazine (SO) is a class of important photochromic dyes for many applications, such as anti-counterfeiting printing, reversible memory photo devices and optical switching elements in molecular electronics. Since these dyes are expensive, improving their coloration efficiency in response to photo stimuli is of practical importance. In this study, a spirooxazine dye, 1,3-dihydro-1,3,3-trimethylspiro[2H-indole-2,3'-[3H]naphtha[2,1-b][1,4]oxazine], was dispersed into the substrate of a polystyrene acrylic latex emulsion to obtain a stable photochromic dye loaded latex. The photochromic latex was then applied on cellulose paper, and its coloration efficiency was significantly higher than the control (without the latex). Transmission electron microscope (TEM) observation revealed that the spirooxazine dye was well dispersed into the matrix of the latex particles, which functioned as a carrier/dispersant for the photochromic dye. Other results, including color stability, and fatigue resistance, were also discussed., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Pre-extraction of hemicelluloses prior to pulping and conversion of the extracted hemicelluloses to other by-products will provide additional revenues to traditional pulp and paper industry. The effects of hemicelluloses pre-extraction with sulfuric acid on aspen (Populus tremuloides) chemi-thermomechanical pulp (CTMP) properties were investigated in this study. The sulfuric acid pre-extraction resulted in a release of 11% of hemicelluloses (determined as xylan) and acetic acid, especially at the second press-impregnation stage. Compared with CTMP without acid pre-extraction, the acid pre-extraction significantly reduced refining energy to a given freeness, and the pulps produced from acid pre-extracted chips have lower shives, higher strength properties except zero-span breaking length, lower bulk, but lower brightness at a similar specific refining energy. This study provides useful information for integration of biorefinery in mechanical pulp mills in the future., (Copyright © 2011 Elsevier Ltd. All rights reserved.)