How do trees support their upright massive bodies? The support comes from the incredibly strong and stiff, and highly crystalline nanoscale fibrils of extended cellulose chains, called cellulose ...nanofibers. Cellulose nanofibers and their crystalline parts—cellulose nanocrystals, collectively nanocelluloses, are therefore the recent hot materials to incorporate in man‐made sustainable, environmentally sound, and mechanically strong materials. Nanocelluloses are generally obtained through a top‐down process, during or after which the original surface chemistry and interface interactions can be dramatically changed. Therefore, surface and interface engineering are extremely important when nanocellulosic materials with a bottom‐up process are fabricated. Herein, the main focus is on promising chemical modification and nonmodification approaches, aiming to prospect this hot topic from novel aspects, including nanocellulose‐, chemistry‐, and process‐oriented surface and interface engineering for advanced nanocellulosic materials. The reinforcement of nanocelluloses in some functional materials, such as structural materials, films, filaments, aerogels, and foams, is discussed, relating to tailored surface and/or interface engineering. Although some of the nanocellulosic products have already reached the industrial arena, it is hoped that more and more nanocellulose‐based products will become available in everyday life in the next few years.
Nanocelluloses, the natural reinforcement for plants, are incredibly strong and stiff, and are therefore under great scrutiny for incorporation in sustainable, ecofriendly, and strong man‐made materials. Nanocelluloses enable dramatic tailoring of surface chemistry, interface interactions, and functionalities via chemical and/or physical surface and interface engineering that permit assembly of diverse nanocellulosic materials. Some of the promising progress in this area is reviewed.
The dendrite issues associated with zinc anode lead to safety hazards and sluggish reaction kinetics, and largely restrain widespread application of aqueous zinc ion batteries (ZIBs). Herein, a ...functional separator composed of cellulose nanofibers and graphene oxide (CG) is developed for dendrite‐free and exceptionally stable ZIBs, realized by uniform hexagonal zinc deposits with manipulated crystallographic orientation (002) plane. This CG separator with negative surface charges and abundant zincophilic‐O groups ensures the strong interaction between the separator and zinc species, simultaneously inducing Zn(002) deposition due to the low mismatch between (002)Zn and (002)GO, thus initiating the preferential orientation of the zinc growth along the horizontal direction due to strong Zn binding ability, and uniform interfacial charge of Zn(002) deposition. Furthermore, the CG separator can effectively promote the uniform nucleation of Zn2+ and eliminate side effects. Accordingly, extremely low polarization of 58 mV at 0.5 mA cm−2, and ultralong cycle life over 1750 h at 2 mA cm−2 and 400 h at 20 mA cm−2 are achieved for the zinc anode. Notably, the CG separator significantly boosts rate capability and cyclability of coin‐type full batteries (Zn||Zn(CF3SO3)2||V2O5, Zn||ZnSO4+MnSO4||MnO2/graphite) and a flexible soft‐packaged battery (Zn||MnO2). Therefore, this work introduces a sustainability consideration in to the design of separators for constructing dendrite‐free ZIBs.
A functional separator composited by cellulose nanofibers and graphene oxide (CG separator) is developed for dendrite‐free and exceptionally stable zinc‐ion batterie, realized by uniform hexagonal zinc deposits with manipulated crystallographic orientation (002) plane in the Zn anode.
Activated carbon/cellulose composite (ACC) biosorbent films were fabricated via solution casting by combining 1–3% w/v of activated carbon with the cellulose solution which dissolved by lithium ...chloride/N, N-dimethylacetamide. Both cellulose solution and activated carbon were prepared from sisal fiber. These films were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscope (FTIR), thermogravimetric analyzer (TGA), and X-ray Diffractometer (XRD). The specific surface area of activated carbon was found to be 1165 m2/g. The maximum methylene blue adsorption capacity of the ACC film reached 103.66 mg/g with the dye concentration of 100 mg/L, solution pH of 6.9, at 35○C for 24 h. The adsorption data suggested that the isotherm model for the equilibrium process was that of Langmuir model, and the adsorption kinetic was best described by pseudo-second-order model. The effect of initial dye concentration (20–100 mg/L), contact time (0–2,880 min), pH (3–11), and temperature (35–80○C) on adsorption capacity of ACC3 film were also examined. Thermodynamics studies of ACC3 film revealed that the adsorption process was endothermic, spontaneous, and feasible. Therefore, the activated carbon/cellulose composite films can be potentially used as biosorbents to remove dyes from contaminated water.
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•Activated carbon/cellulose biocomposite films were prepared using sisal fiber as precursor.•The maximum methylene blue adsorption of the biocomposite films was approximately 103.66 mg/g.•Adsorption data were best described by Langmuir isotherm and pseudo-second-order kinetic models.•Effect of initial dye concentration, contact time, pH, and temperature of biocomposite films were examined.•Thermodynamic results indicated that the adsorption was endothermic and spontaneous.
For the first time, successful fabrication of the cotton aerogels and cotton-cellulose aerogels is achieved using recycled fibers from environmental waste for oil absorption. The pure cotton and ...cotton-cellulose aerogels are obtained using a cost-effective mixing-blending method with polyamide-epichlorohydrin as strengthening additives. The obtained aerogels are silanized using methyltrimethoxysilane via a facile chemical vapor deposition to endow aerogels with hydrophobic surface. Effects of fiber concentrations and cotton-to-cellulose mass ratio on oil absorption performance in various solvents are also investigated. The cotton aerogel with an initial concentration of 0.25wt% presents the highest oil absorption capacity over 100gg−1. Besides, the cotton/cellulose aerogels also demonstrate good absorption capacity in different pollutant organics. The absorption kinetics of the aerogels with different cotton concentrations are also investigated using pseudo first-order model. Both equilibrium absorption and absorption kinetics demonstrate cotton/cellulose aerogels as promising materials for oil absorption and environmental pollution treatment.
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•Cotton aerogel with absorption capacity over 100gg−1 was prepared through simple solution routine.•Silanized cotton and cotton/cellulose aerogel present good hydrophobicity.•Cotton/cellulose aerogels show remarkable absorption capacity in various contaminates.•Cellulose helps to improve absorption reversibility for the composite aerogels.
•Incorporation of silica reduces flammability of viscose fibres.•Wash permanency can be improved by formation of aluminium silicate.•Dyeability of aluminosilicate modified fibres remains ...unchanged.•Silica residues remain during combustion and act as a barrier for oxygen.•Incorporation of silica forms a green approach to flame retardant textiles.
Safety requirements led to widespread use of textile products with reduced flammability. The global production of nearly 3 million tons of flame retardants generates a substantial environmental burden both during synthesis of the chemicals and disposal of waste textiles. In this work a cleaner technology to impart reduced flammability to viscose fibres is presented, which bases on the incorporation of 20%wt of silica into the cellulose fibre matrix during the stage of fibre formation. Stabilisation of the silica against unwanted leaching during washing procedures was achieved by treatment with aluminate, which reacts with silica under formation of the less soluble aluminosilicate. This treatment successfully was combined with the reactive dyeing step where no precipitation of dyes, losses in colour depth or reduced fastness of the dyeings occurred. Substantial reduction in time of afterglowing (-82%) and in length of destroyed material (-90%) were observed in standard tests for ignitability of bedclothes. The incorporation of silica into regenerated cellulose fibres offers a green alternative to the rather polluting finishing processes used today. The use of these modified fibres is of particular value for textile products worn next to the skin, as leaching of irritating flame retardants to the skin can be avoided.
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In this book, the results of the chemical modification of cellulose fibres were presented, aimed at protecting the textile material against biodegradation. Namely, cellulose fibres are highly ...susceptible to microbial attack, resulting in worsened technological and applicable properties of textile products. This is a particularly crucial problem for textiles that are in use. The rate and degree of cellulose biodegradation is affected by several factors, among which the most important are the genera of micro-organisms and the environmental conditions needed for microbial growth.
In recent years, the recycling of waste products has aroused widespread concern. For quality assurance and unpredictable accident, many viscose films or fibers were thrown away as offal, resulting in ...the waste of resources and environmental problems. In this paper, waste viscose films were successfully dissolved in NaOH solution by a simple swelling and shearing method. We studied the effects of NaOH concentration and soaking temperature on the dissolution of waste viscose film, and analyzed the dissolving mechanism. Then, regenerated cellulose fibers were spun successfully from the cellulose solution using H2SO4/Na2SO4 coagulation bath. The mechanical properties of the fibers spun in different coagulation bath and different temperature were tested. The results showed that the mechanical strength of the fibers spun in 10 wt% H2SO4/5 wt% Na2SO4 solution at 30 °C was the best, and the breaking strength of the fibers can reach 215 MPa without drawing. Therefore, this research provides a green and convenient pathway for dissolution and reuse of waste viscose, which has a great application prospect in viscose factory.
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•This research provide a green and convenient pathway to reuse of waste viscose.•NaOH aqueous solution was used to dissolve the waste viscose.•The regenerated cellulose fiber exhibited good tensile strength with 215 MPa.
Sustainable materials fabricated from natural polymers have attracted much attentions because of their multiple advantages like abundant renewable resource, biocompatibility, biodegradability, and ...nontoxicity, while their actually application often restricted by mechanical properties. Chemical crosslinking method was usually used to improve the mechanical properties of cellulose materials such as hydrogel, film, aerogel, and so forth. Here, cellulose fibers were fabricated from cellulose solution in alkali/urea aqueous solvent by chemical crosslinking with epichlorohydrin in a PVC hose. The chemical crosslinked cellulose fibers exhibited smooth surface and circular cross‐section. Their tensile strength increased from 128 to 368 MPa by adjusting cellulose concentration, ECH concentration, and draw ratio. The crystallinity of the fibers changed from 43.1% to 49.8% after drawing process. Meanwhile, the fibers exhibited a brighter color after dyeing than the viscose rayon. This work promising an avenue for preparation of mechanical strong cellulose fibers.
Chemical crosslinked cellulose fibers with good mechanical properties and dyeabilities were fabricated by alkali/urea aqueous solvent.
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•Waste cellulose-derived carbon displays high adsorption capacity for MO.•External pore volume plays an important role in MO adsorption.•Equilibrium can be well fitted with both ...Langmuir and Freundlich isotherms.•Pseudo-2nd-order model predicts kinetics better than the pseudo-1st-order model.
High-performance nitrogen-doped porous carbon adsorbents were prepared from waste cellulose fibers using the spray-drying method and used to remove methyl orange (MO) from water. The carbon adsorbents possessed a honeycomb-like turbostratic microstructure with hierarchical pores. Such waste-cellulose-derived carbon adsorbents were found to exhibit a fast adsorption rate towards MO. A sample thermally treated at 800 °C with the highest specific surface area (about 1259.4 m2/g) and total pore volume (about 2.7 cm3/g) exhibited the best MO adsorption capacity (337.8 mg/g), which is significantly higher than that of ZnCl2-activated carbon. The effect of MO initial concentration, pH and temperature on the carbon adsorption was investigated systematically. It was found that the adsorption system is heterogeneous while the isotherm data on the carbon sample can be well described by both Langmuir and Freundlich isotherm models. The high-performance and cost-effective carbon adsorbent described in this paper holds a great promise for dye removal from aqueous solutions.
Nanocelluloses have unique morphologies, characteristics, and surface nanostructures, and are prepared from abundant and renewable plant biomass resources. Therefore, expansion of the use of ...CO2‐accumulating nanocelluloses is expected to partly contribute to the establishment of a sustainable society and help overcome current global environmental issues. Nanocelluloses can be categorized into cellulose nanonetworks, cellulose nanofibrils, and cellulose nanocrystals, depending on their morphologies. All of these materials are first obtained as aqueous dispersions. In particular, cellulose nanofibrils have homogeneous ≈3 nm widths and average lengths of >500 nm, and significant amounts of charged groups are present on their surfaces. Such charged groups are formed by carboxymethylation, C6‐carboxylation, phosphorylation, phosphite esterification, xanthation, sulfate esterification, and C2/C3 dicarboxylation during the pretreatment of plant cellulose fibers before their conversion into cellulose nanofibrils via mechanical disintegration in water. These surface‐charged groups in nanocelluloses can be stoichiometrically counterion‐exchanged into diverse metal and alkylammonium ions, resulting in surface‐modified nanocelluloses with various new functions including hydrophobic, water‐resistant, catalytic, superdeodorant, and gas‐separation properties. However, many fundamental and application‐related issues facing nanocelluloses must first be overcome to enable their further expansion.
Nanocelluloses have unique morphologies, characteristics, and surface nanostructures, and are prepared from abundant and renewable plant biomass resources. Nanocelluloses can be categorized into cellulose nanonetworks, cellulose nanofibrils, and cellulose nanocrystals, depending on their morphologies. Cellulose nanofibrils have significant amounts of charged groups on their surfaces. These surface‐charged groups can be stoichiometrically counterion‐exchanged to diverse metal and alkylammonium ions.
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