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SEM surface image of (a) cellulose pulp, and Cross-sectional SEM images of the cellulose regenerated using (b) DMAc/LiCl, (c) TFA, and (d) BMICl.
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This paper reports a comparative study on the influence of solvent systems on its structure, properties and electromechanical behavior of cellulose electro-active paper. Three types of solvent systems, namely N,N’-dimethylacetamide (DMAc)/LiCl, Trifluoroacetic acid (TFA) and 1-butyl-3-methylimidazolium chloride (BMICL) were studied to dissolve cell...
Citations
... The samples were scanned at 4000-400 cm −1 , but the regions of interest are the OH stretch region in the 3000-3700 cm −1 range and the amide region at 1100-1710 cm −1 . After the [BMIM][Cl] dissolution of cellulose, the destruction of interand intramolecular hydrogen bonding was observed in the amorphous region, and the existence of glycosidic linkage at 896 cm −1 cm was detected [22]. intermolecular hydrogen bonds [23], as presented in the FTIR spectra, Figure 9. ...
Ionic liquid 1-butyl-3-methylimidazolium chloride [BMIM][Cl] was used to prepare cellulose (CELL), cellulose/polycaprolactone (CELL/PCL), cellulose/polycaprolactone/keratin (CELL/PCL/KER), and cellulose/polycaprolactone/keratin/ground calcium carbonate (CELL/PCL/KER/GCC) biodegradable mulch films. Attenuated Total Reflectance Fourier-Transform Infrared (ATR-FTIR) spectroscopy, optical microscopy, and Field-Emission Scanning Electron Microscopy (FE-SEM) were used to verify the films’ surface chemistry and morphology. Mulch film made of only cellulose regenerated from ionic liquid solution exhibited the highest tensile strength (75.3 ± 2.1 MPa) and modulus of elasticity of 944.4 ± 2.0 MPa. Among samples containing PCL, CELL/PCL/KER/GCC is characterized by the highest tensile strength (15.8 ± 0.4 MPa) and modulus of elasticity (687.5 ± 16.6 MPa). The film’s breaking strain decreased for all samples containing PCL upon the addition of KER and KER/GCC. The melting temperature of pure PCL is 62.3 °C, whereas that of CELL/PCL film has a slight tendency for melting point depression (61.0 °C), which is a characteristic of partially miscible polymer blends. Furthermore, Differential Scanning Calorimetry (DSC) analysis revealed that the addition of KER or KER/GCC to CELL/PCL films resulted in an increment in melting temperature from 61.0 to 62.6 and 68.9 °C and an improvement in sample crystallinity by 2.2 and 3.0 times, respectively. The light transmittance of all studied samples was greater than 60%. The reported method for mulch film preparation is green and recyclable ([BMIM][Cl] can be recovered), and the inclusion of KER derived by extraction from waste chicken feathers enables conversion to organic biofertilizer. The findings of this study contribute to sustainable agriculture by providing nutrients that enhance the growth rate of plants, and hence food production, while reducing environmental pressure. The addition of GCC furthermore provides a source of Ca2+ for plant micronutrition and a supplementary control of soil pH.
... In Fig. 3(a) and (b), the lamellar structure of GO and a strip curl morphology of MCC could be observed. In contrast to original MCC, both D-RC and D-RCGO-I showed uniform a laminated structure after being regenerated from the LiCl/DMAc solution (Mahadeva et al. 2013). Compared with the micromorphology of GO/cellulose composite adsorbent prepared in ionic liquids from the authors' previous work (Hao et al. 2019), the D-RCGO-I membrane was much looser and rougher, which could make it more conducive to efficient adsorption (Fig. 2(d)). ...
A high-efficiency composite adsorbent was synthesized by mixing cellulose and graphene oxide (GO) in the lithium chloride/N,N-dimethyl-acetamide system. The cellulose/GO composite (D-RCGO) was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, elemental analysis, and thermal gravimetric analysis. The influences of various parameters on the removal of Ce(III), such as the adsorbent dosage, temperature, initial Ce(III) concentration, contact time, and pH, were optimized using a range of batch adsorption experiments. Adsorption kinetics displayed adsorption behavior according to the Langmuir isotherm model and pseudo-second-order model. The X-ray photoelectron spectroscopy analysis showed that the two peaks of Ce-3d almost disappeared after the desorption in NaCl solution, which indicated that the adsorption belonged to the ion exchange adsorption mechanism. Furthermore, the theoretical maximum capacity of the adsorption of Ce(III) onto D-RCGO was 225.8 mg·g-1. This work suggested that the D-RCGO composite membranes could serve as an effective and eco-friendly adsorbent for rare earth pollutant removal in wastewater treatment.
... Besides many practical utilization methods such as making pulp and paper, one way of using cellulose is by its dissolved form. Dissolved cellulose can be used to make a variety of products from regenerated textile fibers, packaging films, and cellulose derivatives, which are commercially produced for manufacturing advanced materials, such as separation membrane, hydrogel for bio-medical engineering, electronic devices, and various regenerated nano-fibers depending on their shapes and regeneration methods [3][4][5]. ...
Three alkaline mixtures (NaOH/thiourea, NaOH/urea/thiourea, NaOH/urea/ZnO) and sulfuric acid were used at low temperatures as cellulose solvents, and their cellulose solubility and films’ physical properties for bleached chemical wood pulps and cotton linter were compared. Their degree of polymerization (DP) was controlled to 600–800 before dissolution. Among the alkaline solvents, NaOH/urea/ZnO gave the film the highest tensile strength and stretch. When compared to sulfuric acid, NaOH/urea/ZnO gave lower strength properties but higher crystallinity indices in the films. While alkaline solvents could not dissolve the high DP cellulose (DP ~ 2000), sulfuric acid could dissolve the high DP cellulose at below zero Celsius temperature, and the strength properties of the films were not much different from that of the low DP one. It appeared that the low-temperature sulfuric acid treatment did away with the cellulose’s DP controlling stage; it decreased cellulose DP very quickly for the high-DP cellulose at the initial stage, and as soon as the cellulose DP reached a DP low enough for dissolution, it began to dissolve the cellulose to result in stable cellulose solution.
... A scanning electron microscope, JEOL JSM S400LV EDX Lin l ISIS-Oxford "high vacuum'', was used for the investigation of the surface morphology of the historical leather cover of the manuscript and paper inner lining. SEM was used to scan and identify the types of skin and paper fibers [13,14]. SEM was carried out at the Scanning Electron Microscopy Laboratory, The Central Laboratory Unit, Assiut University, Assiut, Egypt [ . ...
... It was clear by a study of the surface morphology that the cotton fibers appeared polished and accurate. This study was made between two samples: a new sample of cotton fibers [14], and the other from the historical paper inner lining. So, from SEM investigation of the surface morphology, it was clear that the historical paper's inner lining used was similar to the new sample made form cotton fibers, so it is probable that the historical paper's inner lining was cotton fibers (Fig. 7). ...
... Again, it is worth highlighting that it was not possible to form stiff films from CSE/without and CSE/washed samples. A Young's modulus of 3.7 GPa was obtained, which can be explained by the presence of residual solvent trapped in the cellulosic matrix (confirmed by TGA in Figure 2E), as already reported by other authors in some cellulosic regenerated films (Mahadeva et al., 2013). Nevertheless, the yield strength obtained (41.9 MPa) is more than twice that reported in the same work (Mahadeva et al., 2013) and similar to chemically cross-linked cellulose electrolytes (Du et al., 2019), which can be attributed to the partial polymerization promoted by the microwave radiation process. ...
... A Young's modulus of 3.7 GPa was obtained, which can be explained by the presence of residual solvent trapped in the cellulosic matrix (confirmed by TGA in Figure 2E), as already reported by other authors in some cellulosic regenerated films (Mahadeva et al., 2013). Nevertheless, the yield strength obtained (41.9 MPa) is more than twice that reported in the same work (Mahadeva et al., 2013) and similar to chemically cross-linked cellulose electrolytes (Du et al., 2019), which can be attributed to the partial polymerization promoted by the microwave radiation process. It is possible to speculate that the membranes may become slightly more fragile and have a reduction on the elongation to break after some time. ...
One of the most current trends in applied electrochemistry is the development of solid ionic conductors with electrical, mechanical, and optical properties tailored for a specific functional application. Moreover, particular interest exists in materials with low environmental impact and low cost where matters such as sustainability and recyclability are considered. In this study, these concerns were considered by developing a solid-state electrolyte based on regenerated cellulose that meets the requirements for application in electrochromic devices. This soft-matter electrolyte exhibits particularly high room temperature ionic conductivity in the range of 6.5 mS cm–1 and Young’s modulus in the range 3.7 GPa. Optimized electrolyte membranes were applied to inorganic optically active films resulting in all-solid-state electrochromic devices with performances reaching a practical level, retaining its optical modulation characteristics after hundreds of cycles.
... Accordingly, investigations into nanofibers from cellulose have attracted great interest due to their outstanding properties that show high mechanical performance, large ratio of surface area to mass or volume due to small diameter, tunable porosity, and the diversity of surface functional groups [2,3]. Thus, natural fibers obtained from cellulose have widely been used in textile, biomedical, electronic, defense and security, materials, and environmental areas as non-woven fabrics, protecting clothing, wound dressing, tissue scaffolding, drug delivery systems, bandages, enzyme immobilization, electrically conductive fibers, photonic crystals, flexible photocells, biosensors, nano-fiber composites, reinforcement material, mineral processing, propellant applications, food package, paper making, biocatalysts, chemical synthesis, paints, plastics, pharmaceuticals, membranes, and cosmetics, etc. [1,[3][4][5][6][7][8][9][10][11][12][13][14]. Recently, some 1 3 high-technology sectors that include aerospace and nuclear engineering have also considered carbon nanofibers as cheap and environmentally friendly alternative of the materials in current use [15]. ...
... In this context, some lignocellulosic feedstock has been attempted to obtain electrospun cellulose nanofibers. Namely, corn cellulose [6], durum wheat straw [31], rice straw [32], sugar cane straw [33], agricultural residue of coconut palm leaf sheath [34], cotton cellulose [7,12,35], indigo-dyed waste denim garments [36], softwood pulp [9], hardwood kraft pulps [37], cellulose from paper substrates [38], and lignocellulosic sisal [2] are among the materials tested in electrospinning. However, electrospun cellulosic fibers have mostly been fabricated using cellulose acetate (CA) solutions to which various chemicals were added so that the produced fibers have the desired properties according to their intended use. ...
... Cellulose, which is a linear polysaccharide composed of β-(1 → 4) linked glucose, shows high crystallinity supported by extensive hydrogen bonding network [46]. The inter-and intra-molecular hydrogen bonding among the molecules and the van der Waals forces between the non-polar groups make this cheap and abundant raw material undissolved in conventional organic and aqueous solvents [4][5][6][7][8]. An ideal solvent for electrospinning should have the requirements of (i) semi-conductivity with a moderate charge capacity, (ii) 1 3 high volatility for rapid solidification of fiber, and (iii) the ability to dissolve the polymer with minimum intermolecular interactions [12]. ...
Toilet paper was used to produce cellulosic nanofibers through electrospinning method. Dissolution of toilet paper was attempted in either solutions of 0.5–8.5 wt% lithium chloride in Dimethylacetamide (LiCl/DMAc) or Trifluoroacetic acid (TFA). LiCl/DMAc solvent with concentrations lower than 8 wt% was incapable of completely dissolving the toilet paper even though several days of interaction. 8 wt% solvent dissolved the toilet paper, but the obtained solution was too viscous for spinning, and spraying occurred rather than spinning, and hardly visible deposits with fringed structure formed. In contrast, TFA solution dissolved the toilet paper, and the solutions could be spun easily. In these tests, spinning parameters were changed within the feeding rates of 2.00–9.25 mL/h, needle tip-to-collection plate distances of 140–205 mm, voltage of 23–28 kV, and relative humidity of 53–70%. The produced fibers were characterized by Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), and Fourier-Transform Infrared Spectroscopy (FTIR). It was concluded that the produced fibers are ultrafine with nanoscale diameter, and the morphologies of produced fibers are severely in the shape of bead-on-string fibers. Besides, the use of TFA solvent led to reduction in the crystallinity of cellulose that is one of the typical intrinsic characteristics of cellulose.
... By comparing the TGA curves for the extracted cellulose and the regenerated cellulose, respectively, it is clear that the regenerated cellulose starts to decompose at a slightly lower temperature than the extracted cellulose. Studies on wood cellulose has shown that regenerated cellulose from DMAc/LiCl has a slightly lower thermal stability than cellulose before dissolution (Mahadeva et al. 2013) and our data suggest that cellulose from Ulva lactuca shows the same behavior. This is probably caused by the fact that regenerated cellulose has fewer hydrogen bonds between the cellulose chains and also a lower crystallinity than cellulose before dissolution. ...
We report (1) successful extraction and characterization of cellulose from northern hemisphere green macroalgae Ulva lactuca (Ulva fenestrata) collected along the Swedish west coast and cultivated indoors under controlled conditions, followed by (2) its utilization in the production of lignin-free cellulose nanofibrils (CNF). Cellulose was extracted by sequential treatment with ethanol, hydrogen peroxide, sodium hydroxide, and hydrochloric acid, yielding a cellulose-rich insoluble fraction. The extracted cellulose was disintegrated into CNF using a mechanical homogenization process without any further enzymatic pre-treatments. In addition, regenerated cellulose was prepared. XRD characterization of the CNF showed characteristic peaks for the cellulose I allomorph and confirmed that the nanofibrils were semicrystalline with a crystallinity index of 48%. Regenerated cellulose was mostly amorphous with an XRD pattern indicating the presence of the cellulose II allomorph. The cellulose fractions were essentially free from inorganic substances and thermally stable up to around 260 °C. Structural mapping with CP-MAS ¹³C-NMR sustains the cellulose content of CNF and regenerated cellulose, respectively, yet ion chromatography identified the presence of 10–15% xylose in the fractions. Optotracing was used as a novel and non-disruptive tool to selectively assess the polysaccharide composition of the cellulose fractions and produced CNF aiming to shed light on this hitherto non-resolved origin of xylose in Ulva cell wall matter. Fluorescence excitation and emission spectra of a panel of 4 oligothiophenes identified and verified the presence of cellulose and sustain the conclusion that the isolated fractions consist of cellulose intertwined with a small amount of a xylose-containing glucan copolymer.
Graphic abstract
... The micro-scale creep deformation is responsible for the changes in the EAPap structure [35]. The effects of heat treatment, Li + ions, and solvent mixture on the structure, performance, properties, piezoelectricity, and actuation behavior have also been reported [36][37][38][39]. ...
We report on the recent progress and development of research into cellulose-based electro-active paper for bending actuators, bioelectronics devices, and electromechanical transducers. The cellulose electro-active paper is characterized in terms of its biodegradability, chirality, ample chemically modifying capacity, light weight, actuation capability, and ability to form hybrid nanocomposites. The mechanical, electrical, and chemical characterizations of the cellulose-based electro-active paper and its hybrid composites such as blends or coatings with synthetic polymers, biopolymers, carbon nanotubes, chitosan, and metal oxides, are explained. In addition, the integration of cellulose electro-active paper is highlighted to form various functional devices including but not limited to bending actuators, flexible speaker, strain sensors, energy harvesting transducers, biosensors, chemical sensors and transistors for electronic applications. The frontiers in cellulose paper devices are reviewed together with the strategies and perspectives of cellulose electro-active paper and cellulose nanocomposite research and applications.
The drying behavior of regenerated cellulose gel beads swollen with different nonsolvents (e.g., water, ethanol, water/ethanol mixtures) is studied in situ on the macroscopic scale with an optical microscope as well as on nanoscale using small-angle/wide-angle X-ray scattering (SAXS/WAXS) techniques. Depending on the cellulose concentration, the structural evolution of beads during drying follows one of three distinct regimes. First, when the cellulose concentration is lower than 0.5 wt %, the drying process comprises three steps and, regardless of the water/ethanol mixture composition, a sharp structural transition corresponding to the formation of a cellulose II crystalline structure is observed. Second, when the cellulose concentration is higher than 5.0 wt %, a two-step drying process is observed and no structural transition occurs for any of the beads studied. Third, when the cellulose concentration is between 0.5 and 5.0 wt %, the drying process is dependent on the nonsolvent composition. A three-step drying process takes place for beads swollen with water/ethanol mixtures with a water content higher than 20%, while a two-step drying process is observed when the water content is lower than 20%. To describe the drying behavior governed by the cellulose concentration and nonsolvent composition, a simplified phase diagram is proposed.
Solution properties are important physicochemical properties of food hydrocolloids. A number of critical molecular and conformation parameters such as the molecular weight, intrinsic viscosity, radius of gyration, persistence length, etc. are deduced from dilute solutions. The main functionalities of food hydrocolloids, such as viscoelasticity, physical stabilization, emulsification, suspension, mouthfeel, texture modification, delivery of actives, essentially rely on their solution properties. Various hydrocolloids have been widely used in aqueous solution to provide a variety of structures and functionalities to diverse food or non-food products. This chapter starts a brief survey of the main features of the chemical constitution and molecular structures of food hydrocolloids, and then an introduction into the conformation of single chains in solution, using examples for the explanation. After discussing the single chain behavior, the collective properties of polymers, mainly polysaccharides, in bulk are introduced and discussed based on the relevant dilute and semi-dilute solution theory. The impact of molecular parameters and chain conformation of polysaccharides on their solution properties is emphasized, while several molecular and conformation parameters are summarized. The utilization of the solution properties of food hydrocolloids is also described. A series of common polysaccharide liquid crystals are also briefly discussed.
