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The extraction of cellulose nanocrystals from tucum fibers has not been previously reported in the literature. In this way, tucum fibers underwent extraction processes to obtain cellulose nanocrystals, which were then characterized using techniques such as Fourier Transformed Infrared (FTIR), Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), Thermogravimetry (TG), and chemical composition analysis. The results revealed that the cellulose nanocrystals extracted from tucum fibers exhibited a fine, needle-like morphology with lengths ranging from 50 to 350 nm and diameters from 7.5 to 32.7 nm. The chemical composition analysis showed a high presence of alphacellulose in the fibers (ca. 63.38%). FTIR analysis demonstrated characteristic bands of cellulosic materials, while TG analysis indicated higher ash content and lower Tonset in the cellulose nanocrystals. XRD analysis showed increased crystallinity of the nanocrystals. The study underscores the potential applications of these cellulose nanocrystals as reinforcement in nanocomposite materials, emphasizing their eco-friendly and sustainable nature. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The application of hydrogels in the field of wearable flexible sensors has been widely discussed. However, most hydrogels have certain limitations in their mechanical properties, stability and self-recovery, which greatly limits their application in flexible sensors. In this paper, carbon nanotube composite hydrogels with good stability and high tensile properties were prepared by using acrylamide (AM), cellulose nanocrystals (CNC) and multi-walled carbon nanotubes (MWCNTs) as raw materials in water/glycerol by using a one-pot method. The composite hydrogels were characterized by using scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy, and their mechanical properties, conductivity and stability were tested. The results show that the composite hydrogel has a higher elongation at break (596.02%) and a higher tensile strength (0.26 MPa) when the content of cellulose nanocrystals (CNC) is 1 wt%. This is due to the presence of hydrogen bonds and the electrical conductivity of the composite hydrogels can be improved by adding carbon nanotubes (MWCNTs). When 0.06 g carbon nanotubes (MWCNTs) were added, the conductivity of the composite hydrogel reached 0.244 S m−1, showing good conductivity. In addition, the wearable flexible sensor based on the composite hydrogel had a measurement coefficient of 7.20 (400% strain), and the response time and recovery time of the hydrogel were both 150 ms, which is a short response time and can detect human movement. In addition, flexible sensors based on hydrogels can successfully detect finger and wrist movement changes and show good stability. Therefore, carbon nanotube composite hydrogels with good stability and high tensile properties have broad application prospects in the field of wearable flexible sensors. [ABSTRACT FROM AUTHOR]

Scholars are looking for solutions to substitute hazardous substances in manufacturing nanocellulose from bio-sources to preserve the world's growing environmental consciousness. During the past decade, there has been a notable increase in the use of cellulose nanocrystals (CNCs) in modern science and nanotechnology advancements because of their abundance, biocompatibility, biodegradability, renewability, and superior mechanical properties. Spherical cellulose nanocrystals (J–CNCs) were successfully synthesized from Jenfokie micro-cellulose (J–MC) via sulfuric acid hydrolysis in this study. The yield (up to 58.6%) and specific surface area (up to 99.64 m2/g) of J–CNCs were measured. A field emission gun–scanning electron microscope (FEG-SEM) was used to assess the morphology of the J–MC and J–CNC samples. The spherical shape nanoparticles with a mean nano-size of 34 nm for J–CNCs were characterized using a transmission electron microscope (TEM). X-ray diffraction (XRD) was used to determine the crystallinity index and crystallinity size of J–CNCs, up to 98.4% and 6.13 nm, respectively. The chemical composition was determined using a Fourier transform infrared (FT–IR) spectroscope. Thermal characterization of thermogravimetry analysis (TGA), derivative thermogravimetry (DTG), and differential thermal analysis (DTA) was conducted to identify the thermal stability and cellulose pyrolysis behavior of both J–MC and J–CNC samples. The thermal analysis of J–CNC indicated lower thermal stability than J–MC. It was noted that J–CNC showed higher levels of crystallinity and larger crystallite sizes than J–MC, indicating a successful digestion and an improvement of the main crystalline structure of cellulose. The X-ray diffraction spectra and TEM images were utilized to establish that the nanocrystals' size was suitable. The novelty of this work is the synthesis of spherical nanocellulose with better properties, chosen with a rich source of cellulose from an affordable new plant (studied for the first time) by stepwise water-retted extraction, continuing from our previous study. [ABSTRACT FROM AUTHOR]

Nanocellulose is increasingly important due to its abundance and sustainability sources, outstanding physicochemical properties, low density, high specific surface area, and easily modified surface chemistry. Nanocellulose is obtained from various sources, such as plants, algae, and bacteria, with plant-derived nanocellulose being the most common. Their presence significantly benefits many applications, especially in developing advanced materials for high end-use. Despite these benefits, the intrinsic hydrophilic behavior complicates dispersion in hydrophobic polymer matrices due to aggregation issues that result in deterioration properties. Nanocellulose modification and surface tuning are identified as fundamental approaches for improving the compatibility of the interfacial interaction between nanocellulose and polymer matrix to impart new functionalities to novel advanced materials. This article offers insight into nanocellulose by highlighting various lignocellulosic biomass sources and their chemical constituents. Three categories of nanocellulose are discussed in this review, including cellulose nanocrystals, cellulose nanofibrils, and bacterial nanocellulose. This article also featured several methods for promoting surface modification of nanocellulose to overcome the compatibility barrier between nanocellulose and polymer matrix to achieve a balanced hydrophilic-hydrophobic behavior. A few recent and emerging applications of nanocellulose-based composites are also presented in this review. [ABSTRACT FROM AUTHOR]

Nanocelluloses have gained significant attention in recent years due to their singular properties (good biocompatibility, high optical transparency and mechanical strength, large specific surface area, and good film-forming ability) and wide-ranging applications (paper, food packaging, textiles, electronics, and biomedical). This article is a comprehensive review of the applications of nanocelluloses (cellulose nanocrystals, cellulose nanofibrils, and bacterial nanocellulose) in the conservation and restoration of historical paper documents, including their preparation methods and main properties. The novelty lies in the information collected about nanocelluloses as renewable, environmentally friendly, and sustainable materials in the field of cultural heritage preservation as an alternative to conventional methods. Several studies have demonstrated that nanocelluloses, with or without other particles, may impart to the paper documents excellent optical and mechanical properties, very good stability against temperature and humidity aging, higher antibacterial and antifungal activity, high protection from UV light, and may be applied without requiring additional adhesive. [ABSTRACT FROM AUTHOR]

Nanofluids are widely used in seawater desalination, energy conversion, and ion circuits, and the ordered channel structure can improve the ion transport properties of such nanofluids. Biomass-based nanofluids has revealed flaws, such as uncontrollable construction of nanostructure, the weak interaction of structural components, low ionic conductivity, unsatisfactory long-term reliability underwater, and insufficient energy conversion efficiency. Herein, in this study, micronano channel fiber was constructed by self-twisting microfluidic spinning cellulose nanocrystals (CNCs) to obtain aligned nanostructures with an orientation of 0.77. An ordered arrangement and stable bonding formed between the CNCs make their mechanical properties and electrical conductivity improve significantly. It exhibited excellent mechanical properties, with a tensile strength of 450 MPa. The cellulose fibers had a conductivity of 5.5 mS/cm in a 10−5 M KCl solution. The steady-state ordered arrangement micronano channels and regularly arranged hydroxyl functional groups formed by self-twisting effect, which promotes ion transport with higher diffusion coefficient of K+ than Cl−. This work can promote the application of pure cellulose in high-performance osmotic energy conversion systems. [ABSTRACT FROM AUTHOR]

It has attracted tremendous attention for replacing petroleum‐based carbon black or mineral fillers with renewable, biology‐based and low‐cost cellulose. However, the reinforcing effect of cellulose, especially at the microscale, is still a great challenge in the polymer industry. In this work, a feasible surface modification method for microcrystalline cellulose powder (MCC) in all solid states is proposed by using rubber accelerators N‐cyclohexyl benzothiazole‐2‐sulphenamidee (CBS) and 2,2′‐dibenzothiazoledisulfide (DM). These accelerators not only accelerate the sulfur crosslink of nitrile butadiene rubber (NBR), but also graft to rubber molecular chains and form hydrogen bonds with MCC, resulting in good interfacial interaction and good dispersion of MCC in the NBR matrix. As a consequence, the tensile strength and elongation at break of NBR/10MCC reach up to 20.12 MPa and 511%, respectively, which are the highest values of NBR/MCC or cellulose nanocrystals (CNCs) composites we can find in the world and are comparable to those of carbon black or mineral fillers. This provides a more effective and environmentally friendly way of using MCC or CNCs in the polymer industry. Highlights: Microcrystalline cellulose powder can reinforce NBR.Hydrogen bonds have been established between accelerators and MCC.The tensile strength of NBR/10MCC composite reaches 20 MPa.The reinforcing mechanism is ascribed to the immobilized rubber layer. [ABSTRACT FROM AUTHOR]

Epoxy polymers are commonly utilized in structural applications due to their high bearing capacity and excellent chemical resistance. However, their inherent brittleness poses a significant challenge for their use in high shock and fracture strength products. To address this shortcoming, fillers can be incorporated into the polymer during preparation. In this study, we aimed to investigate the effect of incorporating cellulose-based fillers, namely cellulose nanocrystals (CNCs) and microcrystalline cellulose (MCC), on the mechanical properties of epoxy polymer composites. The study evaluated the impact of various factors, including filler concentration, particle size, and moisture content, on the mechanical properties of the composites. The results demonstrated that the incorporation of CNC or MCC powders at concentrations below 5% could enhance the mechanical properties of the resulting epoxy composites without adversely affecting their surface and thermal properties. The maximum tensile strength and fracture toughness of the filler-based epoxy composites were achieved at 2 and 4 wt% for CNCs and MCC, respectively. CNCs with a smaller particle size distribution were found to be much more effective than MCC in improving the mechanical properties of the epoxy composites. Furthermore, utilizing dried fillers resulted in a higher improvement in tensile strength, which was achieved at lower filler concentrations. [ABSTRACT FROM AUTHOR]

L-poly(lactic acid), poly(3-hydroxybutyrate), and poly-hydroxybutyrate-co-hydroxyvalerate are biodegradable polymers that can be obtained from renewable biomass sources. The aim of this study was to develop three types of environmentally friendly film biocomposites of altered microstructure by combining each of the above-mentioned polymers with cellulose nanocrystal fillers and further processing the resulting materials via space-confined solvent vapor annealing. Cellulose was previously obtained from renewable biomass and further converted to cellulose nanocrystals by hydrolysis with the lactic acid. The solutions of biodegradable polymers were spin-coated onto solid substrates before and after the addition of cellulose nanocrystals. The obtained thin film composites were further processed via space-confined solvent vapor annealing to eventually favor their crystallization and, thus, to alter the final microstructure. Indeed, atomic force microscopy studies have revealed that the presence of cellulose nanocrystals within a biodegradable polymer matrix promoted the formation of large crystalline structures exhibiting fractal-, spherulitic- or needle-like morphologies. [ABSTRACT FROM AUTHOR]

Composites based on recycled polypropylene (PP) reinforced with cellulose nanocrystals whit lignin corncob were prepared. The effect of the ratio composites prepared via a compression molding process on the mechanical and thermal properties was analyzed. Corncobs is a little-used agroindustrial residue with a high cellulose content. The corncob was milled and then delignified via the organosolve process in order to get the cellulose unbleached. An acid hydrolysis process was then carried out to obtain lignocellulose nanocrystals (LCNCs). Subsequently, LCNC/PP composites were obtained via termocompression molding using different concentrations of LCNC (0, 0.5, 1 and 2% by weight) previously mixed via extrusion. The residual lignin present in the LCNCs improved the compatibility between the reinforcement and the PP matrix. This was evidenced by the increase in mechanical properties and the stabilization of thermal properties. The results of the mechanical tests showed that the LCNC increases the tensile and flexural modules and strength with respect to neat PP. Composites with 2% of LCNC showed an increase of 36% and 43% in modulus and tensile strength, respectively, while the flexural modulus and strength increased by 7.6%. By using reinforcements of natural and residual origin (corncob) and improving the properties of recycled polymers, their reuse will increase, and this can lead to reducing waste in the environment. [ABSTRACT FROM AUTHOR]

Copyright of Cotton Textile Technology is the property of Cotton Textile Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Increasing mechanical properties without losing electrical properties is of great importance for the development of advanced electronic textile products and their use in different areas. In this study, a cost-effective and facile preparation of MXene/cellulose nanocrystal-coated cotton fabrics by drop-casting was carried out to investigate electrical and mechanical properties of plain woven cotton fabrics. MXene (Ti3C2Tx) and cellulose nanocrystal dispersions of MXene (5 wt.%, 10 wt.% and 15 wt.% cellulose nanocrystal content) were applied to cotton fabrics, and the coated fabrics were characterized in terms of their morphological and structural properties for their suitability for wearable electronics. The surface resistivity and mechanical properties were also determined to evaluate the effectiveness of coating. Ti3C2Tx/cellulose nanocrystal dispersions are suitable to obtain a low electrical resistivity (186.4 Ω/sq) in cotton fabrics. The results also showed that increasing cellulose nanocrystal content results in a more stable coating layer on the cotton fabric and a high tensile (63.2 MPa) and elongation at break values are obtained (30.2%) as a result of that. [ABSTRACT FROM AUTHOR]

Cellulose was isolated from recycled pulp and paper sludge and used to synthesize cellulose nanocrystals. Response surface methodology and Box-Behnken design model were used to predict, improve, and optimize the cellulose isolation process. The optimal conditions were a reaction temperature of 87.5 °C, 180 min with 4% sodium hydroxide. SEM and TEM results revealed that the isolated cellulose had long rod-like structures of different dimensions than CNCs with short rod-like structures. The crystallinity index from XRD significantly increased from 41.33%, 63.7%, and 75.6% for Kimberly mill pulp sludge (KMRPPS), chemically purified cellulose and cellulose nanocrystals, respectively. The TGA/DTG analysis showed that the isolated cellulosic materials possessed higher thermal stability. FTIR analysis suggested that the chemical structures of cellulose and CNCs were modified by chemical treatment. The cellulose surface was highly hydrophilic compared to the CNCs based on the high water holding capacity of 65.31 ± 0.98% and 83.14 ± 1.22%, respectively. The synthesized cellulosic materials portrayed excellent properties for high-end industrial applications like biomedical engineering, advanced materials, nanotechnology, sustainable packaging, personal care products, environmental remediation, additive manufacturing, etc. [ABSTRACT FROM AUTHOR]

Cellulose hydrogel derived from cellulose fibers extracted from printed paper waste is prepared. The hydrogel derived from 3 wt% of the cellulose concentration exhibits a maximum water absorption capacity of 465.5%. The effects of the cellulose hydrogel on the soil moisture are evaluated using four types of soils namely river sand, clayey soil, loamy soil, and gley soil (the wetland soil). The potential application of cellulose‐based hydrogel as an eco‐friendly seed germination media of the paddy seeds under the soil‐less condition is evaluated. This study shows that paddy seeds exhibit a higher seed germination rate of 53% when cellulose hydrogel is used as a seed germination media as compared to seed germination rate ranging from 14% to 35% when various types of soil are used as the germination media. The prepared cellulose hydrogel could be applied as an eco‐friendly and cost‐effective seed germination media to enhance the paddy seeds' germination rate. [ABSTRACT FROM AUTHOR]

In this study, the potential use of nanocrystalline cellulose (CNC) modified epoxy nanocomposite as a matrix is investigated for both glass and carbon fiber-reinforced composites. Various amounts of CNCs (1, 2, 4, and 6 wt%) were added to bisphenol A diglycidyl ether-based epoxy resin (DGEBA), and the optimum CNC loading was determined as 4 wt% in terms of mechanical and thermal properties. Compared to the reference sample containing a neat epoxy matrix with the obtained carbon fiber/CNC-epoxy (CNC/epoxy/CF) and glass fiber/CNC-epoxy (CNC/epoxy/GF) hybrid nanocomposites, significant improvements have been determined in the in-plane shear modulus and strength, and flexural modulus, respectively. The mechanical properties improvements of CNC/epoxy/CF hybrid composites are approximately 0.9% higher than the CNC/epoxy/GF hybrid composites. Additionally, the distribution of CNC in hybrid nanocomposites is also investigated by scanning and transmission electron microscopies. It is noted that the homogenous dispersion of CNCs in the epoxy matrix and their diameters varied from 10 to 100 nm are detected at higher magnification. [ABSTRACT FROM AUTHOR]

Alkali treatment followed by alkalinized hydrogen peroxide delignification yielded 73.90% cellulose from Ensete ventricosum pseudo stem fibre, with parameters optimized using response surface methodology. The optimal reaction parameters were 157 min, 73 °C, and 3.8% NaOH concentration. Thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transfer infrared (FTIR), and scanning electron microscopy were used to examine the thermal properties, crystal structure, chemical structure, and morphological structure of isolated cellulose (SEM). Based on the findings, cellulose has a rod-like shape. The XRD results revealed that the crystallinity index of cellulose increased from 65 to 75% when compared with raw E. ventricosum pseudo stem fibre (Ensete fibre). The resultant cellulose demonstrated relatively higher thermal stability than the unprocessed ensete fibre, according to the thermogravimetric examination. When compared to raw ensete fibre, FTIR analysis revealed that cellulose had a modified chemical functional structure, which suggested that alkali and alkalized hydrogen peroxide treatments had altered the chemical structure of cellulose. As a result of the isolated cellulose's high yield, high crystallinity index, good thermal stability, and morphological structure, cellulose nanocrystals can be extracted. Two step pretreatments were employed to extract cellulose from ensete fibre. Isolated cellulose characterized for it morphological, thermal, functional changes. Cellulose from ensete fibre exhibited good thermal, physical, chemical properties. X-ray diffractometer result depicted that cellulose from ensete fibre has good crystallinity. Cellulose extraction condition was optimized to obtain optimum yield of cellulose. [ABSTRACT FROM AUTHOR]

Cellulose is a promising candidate for the fabrication of superinsulating materials, which would be of great interest for thermal management applications as well as for the scientific community. Until now, the production of strong cellulose‐based aerogels has been dominated by traditional manufacturing processes, which have limited the possibilities to achieve the structural control and mechanical properties seen in natural materials such as wood. In this work, we show a simple but versatile method to fabricate cellulose aerogels in intricate geometries. We take advantage of the 3D printing technique direct ink writing to control both the shape and the thermal‐mechanical properties of the printed cellulose‐based hydrogel inks. Moreover, the shear forces involved in the extrusion process allow us to impart an anisotropic nanostructure to the printed samples. By solvent exchange and supercritical drying, the hydrogel parts are then transformed into stable aerogels. Using X‐ray diffraction analysis, mechanical tests and thermal conductivity tests, our 3D printed aerogels are shown to exhibit directionally dependent thermal‐mechanical properties higher than those reported for earlier cellulose‐based aerogels. These characteristics enable us to fabricate customized structures that can be precisely tailored for their application as load‐bearing insulating materials for thermal management. [ABSTRACT FROM AUTHOR]

Cellulose nanocrystals (CNCs) were successfully extracted and purified from hemp using an alkaline treatment and bleaching process and subsequently used in conjunction with polyvinyl alcohol to form a composite hydrogel. Cellulose nanocrystals (1–10% (w/v)) were integrated into polyvinyl alcohol, and sodium tetraborate (borax) was employed as a crosslinking agent. Due to the small number of cellulose nanocrystals, no significant peak change was observed in the FT-IR spectra compared to pristine polyvinyl alcohol. The porosity was created upon the removal of the water molecules, and the material was thermally stable up to 200 °C. With the presence of cellulose nanocrystals, the melting temperature was slightly shifted to a higher temperature, while the glass transition temperature remained practically unchanged. The swelling behavior was examined for 180 min in deionized water and PBS solution (pH 7.4) at 37 °C. The degree of swelling of the composite with cellulose nanocrystals was found to be higher than that of pristine PVA hydrogel. The cell viability (%) of the prepared hydrogel with different proportions of cellulose nanocrystals was higher than that of pristine PVA hydrogel. Based on the results, the prepared composite hydrogels from cellulose nanocrystals extracted from hemp and polyvinyl alcohol were revealed to be an excellent candidate for scaffold material for medical usage. [ABSTRACT FROM AUTHOR]

Cellulose nanocrystals (CNC) were prepared from delignified kenaf bast fiber by using alkaline pulping, based on soda anthraquinone, hydrogen peroxide bleaching, and acid hydrolysis treatment with H2SO4. The size and morphology of the fibers were characterized by scanning electron microscopy (SEM), and the isolated fiber from unbleached and bleached pulp had a diameter between 9 to 30 µm. Fourier transform infrared (FTIR) spectroscopy exhibited that the content of lignin decreased in the pulping process, and the lignin was almost completely removed during hydrogen peroxide bleaching. Moreover, fibers were characterized for crystallinity using X-ray diffraction (XRD). The fiber crystallinity gradually increased at each stage of the process (raw kenaf bast, unbleached pulp, bleached pulp, and acid hydrolysis). The fiber was characterized by atomic force microscopy (AFM), which showed that the isolated pulp nanofibers had diameters of approximately 30 nm. [ABSTRACT FROM AUTHOR]

This study presents an easy, low-cost, high-yield fabrication method for spherical cellulose nanocrystals (SCNCs) from raw celluloses of eucalyptus pulp (EP) and microcrystalline cellulose (MCC) via a synergetic strategy of swelling-enzymolysis-mechanical treatment. The effects of swelling, enzymolysis, and homogenization on the morphology and properties of the SCNCs obtained from the two raw celluloses were systematically investigated. In comparison with the method that only resulted in low-yield (at most 8%) SCNCs from the supernatants prepared by swelling and enzymolysis of raw celluloses in sequence or simultaneously, high-yield, well-dispersed SCNCs with a high purity of more than 98% was obtained by high-pressure homogenization of centrifugal precipitates of the swollen and enzymatically hydrolyzed raw celluloses. The total yields of SCNCs with diameters of 20–50 nm were ca. 72% and 74% from EP and MCC, respectively. The deconvolution fitting of FT-IR showed that the intermolecular and intramolecular hydrogen bonds related to O(6) within the anhydroglucose unit of cellulose were largely destroyed in the process of enzymatic hydrolysis, which was closely associated with the degradation of partial crystalline regions by endonuclease under high enzyme activity, thus promoting the depolymerization of cellulose and the formation of SCNCs. The crystal structure of the resulting SCNCs did not change. In particular, compared with SCNCs from EP, the SCNCs obtained from MCC possessed high crystallinity (88.5%), thermal stability (decomposition temperature, 341.7 °C), and hydrophobicity. The unique morphology and excellent properties of SCNCs may broaden the application of cellulose-based nanomaterials in high value-added fields. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to find an applicable solution for the consolidation of petrified paper after disassembling it to complete other stages of treatment. Design/methodology/approach: The samples were subjected to natural aging by being inoculated with Aspergillus niger until they reached the stage of adhesion and petrification. After that, the leaves were separated, and cellulose nanocrystals were applied, then the leaves were subjected to wet thermal aging for 21 days. Digital microscope, scanning electron microscope, mechanical properties measurement, measurement of color change, Fourier transform infrared spectroscopy and pH measurement were used to evaluate the effects of the cellulose nanocrystal on paper. Findings: The results proved that cellulose nanocrystal (5%) successes consolidation of petrified paper Without affecting its natural, mechanical and chemical properties. Originality/value: This study was based on the effectiveness of cellulose nanocrystal in strengthening the petrified papers and testing its effect on the physical, mechanical and chemical paper properties. [ABSTRACT FROM AUTHOR]

A vast range of extraction processes, chemistries, and wet processing methods have been explored to improve the opto-mechanical properties of nanocellulosic materials. However, the stresses that arise during drying have been scarcely examined, in particular for their impact on performance. As with papermaking, drying is a critical step that significantly impacts the properties of nanocellulosic materials. The nano- and micro-scaled dimensions of nanocelluloses provide opportunities beyond those achievable in paper science, as the associated drying stresses are several orders of magnitude higher than those at the macroscale. Drying may be utilized towards the generation of assemblies with functional structures and enhanced properties. Herein, we highlight recent examples where such drying stresses are tethered to the structure of nanocellulosic materials. Using cellulose nanocrystals (CNCs), we investigate how the stresses that develop upon consolidation, and that remain thereafter (i.e., residual stresses), correlate with the mechanical performance of the obtained materials. We extend this analysis through results that highlight the impact of the "history" of drying of CNCs on the dynamics of the residual stresses. We also briefly discuss how inhomogeneous concentration gradients in drying suspensions may play an important role in the formation of superstructures across a range of nanocellulosic materials. Overall, by highlighting the importance of drying, we expect a more closely scrutinized science of drying to improve the properties of structures based on nanocellulose. [ABSTRACT FROM AUTHOR]

Due to environmental concerns, as well as its exceptional physical and mechanical capabilities, biodegradability, and optical and barrier qualities, nanocellulose has drawn a lot of interest as a source of reinforcing materials that are nanometer sized. This article focuses on how to manufacture cellulose nanomaterials from cotton by using different types of acids such as H2SO4 and HCI in different concentrations and in the presence of enzymes such as cellulase and xylanase. Two different types of bleaching methods were used before acid and enzyme hydrolysis. In the first method, cellulose was extracted by bleaching the cotton with H2O2. In the second method, NaOCl was utilized. For both methods, different concentrations of acids and enzymes were used to isolate nanocellulose materials, cellulose nanocrystals (CNC), and cellulose nanofibrils (CNF) at different temperatures. All obtained nanocellulose materials were analyzed through different techniques such as FT-IR, Zeta potentials, DLS, Raman spectroscopy, TGA, DSC, XRD, and SEM. The characteristic signals related to cellulose nanocrystals (CNC) were confirmed with the aid of Raman and FT-IR spectroscopy. According to the XRD results, the samples' crystallinity percentages range from 54.1% to 63.2%. The SEM image showed that long fibers break down into small fibers and needle-like features are seen on the surface of the fibers. Using different types of bleaching has no significant effect on the thermal stability of samples. The results demonstrate a successful method for synthesizing cellulose nanofibrils (CNF) from cotton through enzymatic hydrolysis, but the results also demonstrated that the choice of bleaching method has a significant impact on the hydrodynamic properties and crystallinity of both CNC and CNF samples. [ABSTRACT FROM AUTHOR]

This research study reports on the extraction of nanocellulose followed by structural and thermal analysis and application of nanocellulose in hydroxypropyl methyl cellulose (HPMC) nanocomposite films. The cellulose nanocrystals were isolated from Artemisia scoparia straw through an alkaline treatment and bleaching process, followed by sulphuric acid hydrolysis. The HPMC nanocomposite films were prepared by a solution casting method and dried at room temperature. Fourier transform infrared-ray (FTIR) spectroscopy and thermogravimetric analysis (TGA) techniques were used to analyze the structural and thermal properties of the materials, including the cellulosic material, the nanomaterial, and the nanocomposites. The FTIR spectra indicated that the extraction procedure was adequate, demonstrating the removal of lignin and hemicellulose and the preparation of nanocellulose. The TGA results revealed the thermal degradation pattern of the cellulose and showed that the HPMC films had enhanced thermal stability. This research demonstrates that A. scoparia straw has potential for the extraction of cellulosic nanomaterial and a wide range of applications in nanocomposites. [ABSTRACT FROM AUTHOR]

In this paper, a set of methods was used to study the structural characteristics and properties of cellulose nanocrystallites and free cellulose nanocrystalline particles (CNCs). It was shown that cellulose nanocrystallites have three main distinctive features. The first distinctive feature of cellulose nanocrystallites is their rod-like shape with a quite high aspect ratio and a low percolation threshold. The second distinctive feature of nanocrystallites is their highly developed specific surface area that leads to the spontaneous crystallization and aggregation of rod-like crystallites by their lateral planes. This aggregation process is thermodynamically favorable because it leads to a decrease in the specific surface area of nanocrystallites and a reduction of the thermodynamic potential. The third distinctive feature of cellulose nanocrystallites is the paracrystalline structure of their surface layers, which significantly affects structural characteristics such as lattice distortion, interplanar spacings, parameters, and volume of the crystalline unit cell, etc. The paracrystalline fraction affects also important physical and physical-chemical properties of cellulose, such as accessibility to deuteration, the content of CII-allomorph after cellulose alkalization, the melting point of nanocrystallites, etc. Correlation equations were derived that provide to predict the structural characteristics and properties of nanocrystallites using the content of the paracrystalline fraction. [ABSTRACT FROM AUTHOR]

Primary material supply is the heart of engineering and sciences. The depletion of natural resources and an increase in the human population by a billion in 13 to 15 years pose a critical concern regarding the sustainability of these materials; therefore, functionalizing renewable materials, such as nanocellulose, by possibly exploiting their properties for various practical applications, has been undertaken worldwide. Nanocellulose has emerged as a dominant green natural material with attractive and tailorable physicochemical properties, is renewable and sustainable, and shows biocompatibility and tunable surface properties. Nanocellulose is derived from cellulose, the most abundant polymer in nature with the remarkable properties of nanomaterials. This article provides a comprehensive overview of the methods used for nanocellulose preparation, structure–property and structure–property correlations, and the application of nanocellulose and its nanocomposite materials. This article differentiates the classification of nanocellulose, provides a brief account of the production methods that have been developed for isolating nanocellulose, highlights a range of unique properties of nanocellulose that have been extracted from different kinds of experiments and studies, and elaborates on nanocellulose potential applications in various areas. The present review is anticipated to provide the readers with the progress and knowledge related to nanocellulose. Pushing the boundaries of nanocellulose further into cutting-edge applications will be of particular interest in the future, especially as cost-effective commercial sources of nanocellulose continue to emerge. [ABSTRACT FROM AUTHOR]

A surfactant with biodegradability and amphiphilicity was prepared from cellulose nanocrystals by grafting fatty acids. The structure of the modified cellulose nanocrystals was investigated by infrared spectroscopy, XRD, particle size detection and scanning electron microscopy. The changes in surface tension of the modified cellulose nanocrystals under different salt ion concentrations and pH were tested, and the molecular model of the modified cellulose nanocrystals was constructed. The optimum reaction conditions for the grafting of different fatty acid groups were determined by the degree of substitution. Infrared characterization and X-ray diffraction analysis showed that the reactants were successfully esterified and chemically modified. The particle detection shows that the average particle size of the modified cellulose nanocrystals is slightly increased, but it is still at the nanometer level and still has large specific surface area. The surface tension of the surfactant in the aqueous phase will decrease by changing the salt concentration and pH of the test environment, while the range is not large. Therefore, using trifluoroacetic anhydride as co-reactant, long-chain fatty acids can be grafted onto cellulose nanocrystals to form hydrophobic modified cellulose nanocrystals. The modified cellulose nanocrystals have little change in average particle size and have hydrophilic and lipophilic properties and are nonionic surfactants, which can be used as emulsifier for emulsion preparation. It is found that the modified cellulose nanocrystals have good salt resistance and acid and alkali resistance by testing the changes in surface tension under different environments. [ABSTRACT FROM AUTHOR]

Unsatisfactory macroscopic strength is one of the important reasons that limit the application of cellulose composites. However, the mechanical properties of cellulose composites could be improved by the directional orientation of cellulose nanofibers. In this paper, a five-channel microfluidic chip was designed to fabricate core-sheath cellulose nanocrystal/ cationic polyacrylamide (CNC/CPAM) composite filament. The core spinning solution with high flow velocity promoted the extended arrangement of CPAM in sheath flow. CPAM with long chain structure could not only reduce the electrostatic repulsion between CNCs, but also ensures the fiber orientation by inhibiting the disorderly diffusion of CNCs, thus improving the toughness of the composite filament. The orientation of the composite fiber was studied by wide-angle X-ray scattering, showing an orientation index of 0.725. The mechanical properties of the composite fiber were tested by a universal material testing machine. The tensile strength was 510 ± 20 MPa, which was about 117% higher than that of pure CNC spun fiber, and the elongation at break was also increased by about 70%. The improvement in mechanical properties was attributed to the increase in the content of intramolecular and intermolecular hydrogen bonds. In addition, the demonstrated spinning technology provided a new way for preparing high-performance composite fibers. [ABSTRACT FROM AUTHOR]

Copyright of Momento: Revista de Física is the property of Universidad Nacional de Colombia, Departamento de Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Structural coloration has become a fascinating field of research, inspiring scientists and engineers to explore the vibrant colors observed in nature and develop bio-inspired photonic structures for various applications. Cellulose-based materials derived from plant fibers offer a promising platform for mimicking natural photonic structures. Their abundance, renewability, and versatility in form and structure make them ideal for engineering specific optical properties. Self-assembly techniques enable the creation of ordered, periodic structures at the nanoscale by manipulating the interactions between cellulose fibers through chemical modification or physical manipulation. Alternatively, additive manufacturing techniques like 3D printing and nanoimprint lithography can directly fabricate desired structures. By em-ulating natural photonic structures, cellulose-based materials hold immense potential for applications such as colorimetric sensors, optoelectronic devices, camouflage, and decorative materials. However, further research is needed to fully com-prehend and control their optical properties, as well as develop cost-effective and scalable manufacturing processes. This article presents a comprehensive review of the fundaments behind natural structural colors exhibited by living organisms and their bio-inspired artificial counterparts. Emphasis is placed on understanding the underlying mechanisms, strategies for tunability, and potential applications of these photonic nanostructures, with special focus on the utilization of cellulose nanocrystals (CNCs) for fabricating photonic materials with visible structural color. The challenges and future prospects of these materials are also discussed, highlighting the potential for advancements to unlock the full potential of cellulose-based materials with structural color. [ABSTRACT FROM AUTHOR]

Films of cellulose nanocrystals (CNCs) with chiral nematic organization can show vivid iridescence that arises from their hierarchical structure. Unfortunately, the brittleness of the films limits their potential applications. In this paper, we investigate the incorporation of halloysite nanotubes (HNTs) into CNC films to prepare organic–inorganic composite films with enhanced mechanical properties, while preserving the chiral nematic structure and brilliant iridescence. The hybrid composite films containing 10 wt% HNTs are more elastic than pristine CNC films, with a 1.3-fold increase in tensile strength and a 1.6-fold increase in maximum strain. As well, the incorporation of HNTs slightly improves the thermal stability of the composite films. These materials mimic the hybrid composite structures of crab shells, leading to enhanced mechanical properties and thermal stability of CNC films while maintaining iridescence. [ABSTRACT FROM AUTHOR]

Sugarcane bagasse fiber cellulose nanocrystals (SBFCNC) and microcrystalline cellulose-derived-cellulose nanocrystals (MCC-CNC) were extracted from sugarcane bagasse fiber (SBF; an agricultural waste) and microcrystalline cellulose (MCC), respectively. Both SBFCNC and MCC-CNC were synthesized using sulfuric acid hydrolysis followed by the freeze-drying method. Both MCC-CNC and SBFCNC show stable suspension in water with zeta potential values of – 40.5 mV and – 42.2 mV, respectively. Transmission electron microscopy (TEM) analysis revealed that the SBFCNC has a higher aspect ratio (l/d = 65) compared to the MCC-CNC (l/d = 25). The poly(lactic acid) (PLA) nanocomposites containing of MCC-CNC and SBFCNC was prepared using solvent casting method, and the films are highly amorphous as evidenced from the differential scanning calorimetry (DSC) study. The tensile strength of PLA/SBFCNC-10 is higher than that of PLA/MCC-CNC-10 films. Thermogravimetric analysis (TGA) results showed that the thermal stability of PLA was improved significantly by the incorporation of MCC-CNC and SBFCNC. Poly(lactic acid)/SBFCNC-15 nanocomposites exhibited higher UV shielding properties (i.e., a UV blocking ratio of 0.63–0.66 in the UVA, UVB, and UVC regions) compared to PLA/MCC-CNC-15 nanocomposites (a UV blocking ratio in the range of 0.38–0.54). Sugarcane bagasse fiber cellulose nanocrystal is a potential biofiller that can provide good thermal stability and UV shielding properties for green bionanocomposites, which can give it an opportunity for food packaging applications. [ABSTRACT FROM AUTHOR]

Copyright of Packaging & Food Machinery is the property of Packaging & Food Machinery Magazine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Biopolymers that mimic the extracellular matrix are favourable in tissue engineering. However, the rapid degradation and the lack of mechanical and enzymatic stabilities of these biopolymers prompt researchers to composite different biopolymers. In this study, we aim to develop an acellular gelatin-chitosan-cellulose nanocrystal (GCCNC) scaffold as a potential wound dressing. The GCCNC mixture was homogenised via ultrasonication and the genipin crosslinking was performed by magnetic stirring. The mixture was then frozen at − 80 °C for 6 h and freeze-dried. The effects of different ratios of gelatin and chitosan with cellulose nanocrystals on the physiochemical properties, mechanical properties, and cellular biocompatibility were studied. Our results herein showed that G3C7CNC demonstrated a homogenous interconnected porous structure with a good porosity (67.37 ± 9.09%) and pore size (148.46 ± 48.68 µm), acceptable swelling ratio (1071.11 ± 140.26%), adequate water vapour transmission rate (315.59 ± 25.27 g/m2/day), low contact angle (70.21 ± 6.79°), and sufficient mechanical strength (modulus of 64.67 ± 12.42 MPa). The lower biodegradation rate in the G3C7CNC (0.06 ± 0.01 mg/hr) compared to G10CNC (0.48 ± 0.07 mg/hr) together with the absence of glass transition phenomenon indicated an increase in both enzymatic and thermal stabilities. Furthermore, G3C7CNC was non-cytotoxic and biocompatible with human epidermal keratinocytes (HEKs) and human dermal fibroblasts (HDFs). The presence of collagen type I and α-smooth muscle actin expression in HDFs, together with the expression of cytokeratin-14 in HEKs, demonstrated our scaffold's ability to maintain normal skin physiological functions. Therefore, this study proposes that the fabricated GCCNC scaffold could serve as a potential acellular skin substitute in managing chronic wounds. [ABSTRACT FROM AUTHOR]

Poly(L‐lactic acid) (PLLA) is a biodegradable polymer that has attracted increasing attention due to its fantastic properties. Nevertheless, the disadvantages of PLLA, such as low crystallization rate and brittleness, limit its wide commercial applications. In the present work, electrospun stereocomplex PLA fibers (Sc‐fibers) and PLLA grafted cellulose nanocrystals (g‐CNCs) are prepared as nano‐fillers and then blended with PLLA matrix to prepare different nanocomposites. Both of nano‐fillers would accelerate the crystallization rate of PLLA, and as expected, g‐CNCs have much stronger nucleation ability towards PLLA than Sc‐fibers. Nevertheless, the crystallization of PLLA will decrease to some extent in the presence of both nano‐fillers of g‐CNCs and Sc‐fibers due to the preferential formation of stereocomplex crystals on the surfaces of CNCs. Moreover, the presence of nano‐fillers would enhance the mechanical properties of PLLA, such as the elongation at break can increase by four times after incorporating both g‐CNCs and Sc‐fibers. This work provides a new consideration for designing different nano‐fillers, especially for polymer matrices with low crystallization ability and brittleness. [ABSTRACT FROM AUTHOR]

The study was used in the context of realigning novel low-cost materials for their better and improved optical properties. Emphasis was placed on the bio-nanocomposite approach for producing cellulose/starch/silver nanoparticle films. These polymeric films were produced using the solution casting technique followed by the thermal evaporation process. The structural model of the bio-composite films (CS:CL-CNC7:3–50%) was developed from our previous study. Subsequently, in order to improve the optical properties of bio-composite films, bio-nanocomposites were prepared by incorporating silver nanoparticles (AgNPs) ex situ at various concentrations (5–50% w/w). Characterization was conducted using UV-Visible (UV-Vis), Fourier Transform Infrared (FTIR), Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM) to understand the structure–property relationships. The FTIR analysis indicated a reduction in the number of waves associated with the OH functional groups by adding AgNPs due to the formation of new hydrogen bonds between the bio-composite matrix and the CL-WE-AgNPs. Based on mathematical equations, the optical bandgap energy, the energy of Urbach, the edge of absorption (Ed), and the carbon clusters (N) were estimated for CS:CL-CNC and CS:CL-CNC-AgNPs (5–50%) nanocomposite films. Furthermore, the optical bandgap values were shifted to the lower photon energy from 3.12 to 2.58 eV by increasing the AgNPs content, which indicates the semi-conductor effect on the composite system. The decrease in Urbach's energy is the result of a decrease in the disorder of the biopolymer matrix and/or attributed to an increase in crystalline size. In addition, the cluster carbon number increased from 121.56 to 177.75, respectively, from bio-composite to bio-nanocomposite with 50% AgNPs. This is due to the presence of a strong H-binding interaction between the bio-composite matrix and the AgNPs molecules. The results revealed that the incorporation of 20% AgNPs into the CS:CL-CNC7:3–50% bio-composite film could be the best candidate composition for all optical properties. It can be used for potential applications in the area of food packaging as well as successfully on opto-electronic devices. [ABSTRACT FROM AUTHOR]

Nanocellulose has a wide range of applications in the field of functional materials, and it has piqued the interest of researchers for some time. This is because nanocellulose inherits the advantages of environmental friendliness and easy availability of plant cell walls in nature, as well as the unique morphology of nanostructures. This review presents four types of nanocellulose including cellulose nanocrystals (CNCs), cellulose nanofibrils (CNFs), regenerated nanocellulose (RNC) and bacterial cellulose (BC), introduces the different preparation routes and their mechanisms, analyzes the advantages and drawbacks between these approaches, and summarizes the potential applications in the field of functional materials such as reinforced composite materials, biomedical materials, soft templates, and optical materials. Finally, future development directions are proposed including further enrichment of nanocellulose raw materials, improvement of preparation methods to adapt to more diversified raw materials, and classification of products according to their morphology and properties to improve the use efficiency. [ABSTRACT FROM AUTHOR]

In this study, spherical cellulose nanocrystals have been extracted from Gai bamboo (Bambusa blumeana) fibers by sulfuric acid hydrolysis methods. The removal of amorphous components, lignin, and hemicellulose in raw bamboo fiber and the incorporation of sulfate groups were explored via the changes of bond's vibration in Fourier‐infrared spectra and the decrease of onset temperature of thermogravimetric diagram. The results from transmission electron microscopy and X‐ray diffraction revealed that the nanocellulose has a spherical shape with a diameter of 2 to 10 nm and the crystallization index of 70.30% and crystallization degree of 0.77. The improvement of thermal and mechanical properties of the chitosan films loaded with spherical nanocellulose were evaluated. Interestingly, the tensile strength, modulus, and elongation at break for chitosan film loaded with spherical nanocellulose were all increased. The highest value achieved with chitosan film containing nanocellulose of 2 phr. The increase values of tensile strength, modulus and elongation at break were of 63%, 207 MPa, and 30%, respectively. In addition, the moisture absorption of the chitosan film was decreased to 20% indicating that the barrier properties have improved. These improvements illustrated the advancement of nano sized of spherical nanocellulose and the chemical compatibility between nanocellulose and chitosan that resulted in well‐dispersion of nanocellulose in chitosan matrix, developed high performance bionanocomposite. [ABSTRACT FROM AUTHOR]

The surface functionalization of cellulose nanocrystals is presently considered a useful and straightforward tool for accessing very reliable biocompatible and biodegradable nanostructures with tailored physical and chemical properties. However, to date the fine characterization of the chemical appendages introduced onto cellulose nanocrystals remains a challenge, due to the low sensitivity displayed by the most common techniques towards surface functionalization. In this paper, we demonstrate the easy functionalization of cellulose nanocrystals with aliphatic and aromatic amines, demonstrating the tunability of their properties in dependence on the selected functionality. Then, we apply to colloidal suspensions of modified nanocrystals 1H NMR analysis to elucidate their surface structure. To the best of our knowledge, this is the first report where such investigation was performed on cellulose nanocrystals presenting both surface and reducing end modification. These results involve interesting implications for the fields of cultural heritage and of materials chemistry. [ABSTRACT FROM AUTHOR]

Carbon-based solid acids (CSA) have grown in popularity in recent years owing to their strong catalytic activity, thermal stability, and reusability. The size effect has a significant influence on the catalytic activity of carbon-based solid acids in heterogeneous catalysts. The impacts of raw material size on the shape, sulfonation degree, and catalytic activity of produced carbon-based solid acids were examined in this article. Various sizes of microcrystalline cellulose (MCC), cellulose nanocrystals (CNCs), and cotton fiber pulp (CP) were used as carbon sources in a simple carbon-sulphonation method to synthesize carbon-based solid acids. The produced CSA has a high concentration of sulphonic acid groups, as well as hydroxyl and carboxyl groups, and exhibits remarkable catalytic activity for the conversion of xylan to xylose. The solid acids generated from MCC have the most homogeneous shape, the greatest degree of sulphonation, and the highest catalytic activity. The conversion rate of xylan hydrolysis to xylose was up to 58.8% under ideal reaction conditions (150 °C, 4 h), and the catalyst retained almost its initial level of activity after five cycles with no appreciable deactivation. [ABSTRACT FROM AUTHOR]

This study explored the impact of cellulose-derived fillers, cellulose nanofibers (CNFs) and cellulose nanocrystals (CNCs), on the microstructure and texture of potato protein hydrogels (20 wt% protein). Particle size analysis, surface charge analysis, and molecular docking simulations suggested that the cellulose nanofibers and nanocrystals acted as inactive fillers within the potato protein matrix. Texture profile analysis showed that incorporation of small amounts of CNFs (<1%) increased the gel strength (by up to 69%), but the addition of larger amounts decreased it, which was attributed to disruption of the protein network by aggregated nanofibers at higher concentrations. The incorporation of CNCs had a much smaller effect on the gel strength of the potato protein hydrogels, only increasing it by up to 15% at 2% CNC. Shearing the cellulose-reinforced hydrogels in a shear rheometer had little impact on their gel strength at lower filler concentrations (<2 wt%) but increased it at higher concentrations. Microscopy analysis showed that the cellulose fibers could be aligned at sufficiently high shearing rates, leading to a fibrous microstructure. This study provides valuable insights into the optimization of the properties of cellulose fillers for application in plant protein hydrogels. In particular, it suggests that they may be utilized in plant-based meat analogs to enhance their textural attributes and optimize their appearance. [Display omitted] • Cellulose nanofibers (CNFs) and nanocrystals (CNCs) were used as fillers to reinforce protein hydrogels. • CNFs gave a greater increase in gel strength than CNCs in potato protein hydrogels. • The impact of fillers on the elastic modulus of the composite hydrogels was modeled. • Shearing caused CNFs to form aligned fiber structures but had a little impact on CNCs. [ABSTRACT FROM AUTHOR]

Nanocellulose, as the most abundant natural nanomaterial with sustainability, biodegradability, and excellent mechanical properties, has been widely applied in modern electronic systems, particularly, in the flexible electrochemical energy storage devices. Herein, a reduced graphene oxide (RGO)/cellulose nanocrystal/cellulose nanofiber (RCC) composite membrane was prepared by using a one-pot method. Compared to the pure RGO membranes, the RCC composite membranes exhibited better mechanical properties and hydrophilicity. Furthermore, due to the synergistic effect of nanocellulose and RGO sheets, the RCC composite membrane exhibited a specific capacitance as high as 171.3 F·cm−3. Consequently, a nanocellulose-based symmetric flexible all-solid-state supercapacitor (FASC) was constructed, in which two RCC composite membranes served as electrodes and a porous cellulose nanofiber membrane acted as separator. This fabricated FASC demonstrated a high volumetric specific capacitance of 164.3 F·cm−3 and a satisfactory energy density of 3.7 mW·h·cm−3, which exceeded that of many other FASCs ever reported. This work may open a new avenue in design of next-generation nanocellulose based, sustainable and flexible energy storage device. • RGO/CNC/CNF composite membranes were prepared by using a facile one-pot method. • "Brick-and-mortar" microstructure was observed in composite membranes. • An all nanocellulose-based supercapacitor was assembled. • The nanocellulose-based supercapacitor showed desired specific capacitance. • The assembled supercapacitor exhibited high energy density and power density. [ABSTRACT FROM AUTHOR]

The major by-product of bambooworking (i.e. making items from bamboo) is bamboo sawdust, which is a waste product from bambooworking operations and can cause human health hazards. Specifically, this experimental research investigates the effects of acid treatment methods on the physicochemical characteristics of nanocellulose fibers from bamboo sawdust. The experimental acid treatment methods are sulfuric acid hydrolysis for bamboo fiber nanocrystal cellulose (BBF-NCC) and sulfuric acid dissolution for bamboo fiber amorphous cellulose (BBF-AC). The physicochemical properties of nanocellulose from bamboo sawdust include the crystalline structure, morphology, and colloidal stability. The experimental results indicate that BBF-NCC possesses a higher crystallinity index (89.5%), in comparison with 35.4% for BBF-AC. The BBF-NCC is of rod shape with 10 nm in diameter and 50–100 nm in length, while BBF-AC coalesces into clusters of varying sizes. In addition, BBF-NCC possesses higher colloidal stability than BBF-AC, as indicated by a zeta potential of −30.93 mV for BBF-NCC, compared with −19.73 mV for BBF-AC. Essentially, this research is the first to experimentally convert bamboo sawdust into cellulose nanofibers as an eco-friendly and economically viable solution to the waste problem from the bamboomaking industry. Moreover, BBF-NCC and BBF-AC could potentially be adopted as a reinforcing agent in biocomposites or as a carrying agent in multiple applications. [ABSTRACT FROM AUTHOR]

The inclusion of cellulose nanocrystals (CNC) and microcrystalline cellulose (MCC) during extrusion processing of corn starch (CS) is presented in this study. Blends were prepared by incorporating CNC and MCC at different concentrations, 1%, 3%, 5%, and 10% w/w in CS. The crystallinity index (CrI) of CNC and MCC was determined using X‐ray diffraction, and the chemical functionality of CNC, MCC, and CS was studied using Fourier transform infrared spectroscopy. The pasting properties of the blends were studied using Micro Visco‐Amylo‐Graph before extrusion. The blends were preconditioned to 18 ± 0.5% (w.b.) moisture and extruded using a twin‐screw extruder at 200 and 250 rpm at 140°C. CS‐CNC's expansion ratio (ER) values were 2.95 to 3.35 and 2.72 to 3.22 for MCC. CNC's CrI and particle size were significantly lower than MCC, allowing CNC‐based extrudates to have ER values similar to the control even at high CNC concentration (≤10% w/w). This study demonstrated that fiber with particle size <100 µm can be added in direct‐expanded product formulations at high concentrations without negatively influencing the extrudate texture while offering increased nutritional value. Practical Application: This study gives insight into the potential application of cellulose nanocrystals and microcrystalline cellulose in manufacturing direct‐expanded extruded products, providing high fiber content without compromising the product quality. This knowledge could also be translated into manufacturing other food products such as breakfast cereals, pasta, and bread. [ABSTRACT FROM AUTHOR]

The need for natural, biodegradable, and biocompatible nanomaterials in drug delivery led to a great deal of interest in developing nanocellulose-based materials. This article emphasizes the potential of different types of nanocellulose in improving targeted intracellular drug delivery of biological and non-biological therapeutic molecules. Several new concepts and methods of employing nanocellulose to deliver therapeutic molecules, including less-studied biological agents, have been reviewed. Different types of nanocellulose, methods to extract or synthesize them, and various factors like size, shape, surface charge, hydrophilicity, etc. that affect intracellular drug delivery have also been discussed. Lastly, we discuss the current limitations associated with the extraction/synthesis of nanocellulose and its usage in targeted drug delivery, along with future prospects, including possible solutions to address the current challenges. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Crotalaria juncea bast fibers a novel cellulose rich material is valorized by producing cellulose nanocrystals (CNCs) which gained much attention due to its unique properties. CNCs obtained during this study consisted of two steps: pretreatment of C. juncea fibers to obtain chemically purified cellulose followed by sulfuric acid hydrolysis. Efficacy of two different pretreatment methods chlor-alkali method (pre-treatment-I) and ultra sound assisted chlorine free alkaline peroxide (pre-treatment-II) methods was examined for CNC preparation. Pre-treatment-I was found to be more effective yielding higher crystallinity and higher surface sulfate ester groups containing CNCs compared to CNCs obtained using pre-treatment-II. Moreover the cellulose structure was altered with more pure cellulose-I structure obtained from pretreatment- I. The process conditions of pre-treatment – I was optimized for CNC preparation. The acid concentration of 80%(w/v) was found to be optimized to produce CNCs with~43% yield, 80.9% crystallinity index having a rod-like structure (Length −120 ± 26 nm and diameter − 25 ± 5.5 nm). The surface charge density of the optimized CNC was found to be 0.34 meqv/g and a zeta potential −27.7 mV was recorded emphasizing stable dispersion. [ABSTRACT FROM AUTHOR]