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This study provides a comprehensive analysis of the effects of incorporating low levels of cellulose nanofibrils (CNFs) into an acrylonitrile butadiene styrene (ABS) matrix on the properties of ABS composites. Five samples with varying CNF content (0.125%, 0.25%, 0.5%, and 1%) were prepared, alongside a pure ABS sample for comparison. The preparation involved mechanical blending, followed by extrusion and injection molding. Mechanical, thermal, water absorption, surface gloss, and microstructural properties of the composites were characterized. Tensile and three-point bending tests revealed that the addition of CNFs improved both stiffness and strength, with the highest tensile modulus observed in ABS/NC4 (1% CNFs) and the highest flexural strength in ABS/NC1 (0.125% CNFs). Impact resistance, evaluated through Charpy impact testing, showed enhancement up to 0.5% CNF content, beyond which a decline was observed due to increased particle quantity. Thermal properties exhibited negligible changes, with slight variations in glass transition and melting temperatures observed within a narrow range. SEM analysis confirmed a uniform distribution of CNFs, contributing to enhanced crack resistance, although higher CNF content led to increased void formation. Surface gloss measurements indicated smoother material surfaces with higher CNF content. The study concludes that integrating CNFs into ABS composites improves mechanical properties and impact resistance, necessitating careful consideration of CNF content for optimal performance. Further refinement could tailor ABS/CNF composites for specific applications. [ABSTRACT FROM AUTHOR]

The main purpose of this study was to investigate effects of various electrospinning parameters on the morphology and diameter of cellulose nanofibril (CNF) filled polylactide (PLA) nanofibers. For this purpose, first of all effects of three important electrospinning parameters; polymer solution concentration, solution feeding rate and collector distance to feeding tip were studied. Then, effects of using higher amount of CNF, effects of using cellulose nanocrystal (CNC) particles, and effects of adding potassium chloride salt were also investigated. It was observed that when optimum electrospinning parameters were determined, then it was possible to obtain almost "bead-free" morphology and "finest" average diameter of 232 nm for PLA/CNF electrospun fibers. Increasing values of feeding rate and collector distance parameters resulted in bead formation and thicker diameters. On the other hand, increasing CNF amount, using CNC particles and adding KCl salt, all resulted in further decreases in the diameter down to 152 nm; mainly due to increased charge density of the polymer solution. Moreover, in vitro degradation analysis of all types of electrospun nanofiber mats in a simulated body fluid revealed that increasing the immersion period increased their degradation rate in terms of "% weight loss". It was also observed that, mats with fine diameter fibers had higher degradation rate. [ABSTRACT FROM AUTHOR]

Developing biodegradable material alternatives is crucial to address the fossil-based plastic pollution in marine ecosystems. Natural biodegradable polymers like cellulose exhibit potential plastic alternatives. However, their susceptibility to water and moisture poses challenges when blending with hydrophobic polymers. Thus, chemical modification is often required to enhance cellulose dispersion in hydrophobic polymer matrices, which may hinder its inherent biodegradability. In this study, the aquatic biodegradation and degradation mechanisms of lignocellulose-polyester composite films under aerobic conditions were for the first time explored in simulated freshwater and real seawater environments. The composite films were produced by blending cellulose nanofibrils (CNFs) with polycaprolactone (PCL), a hydrophobic polyester, using lignin nanoparticles (LNPs) as an interfacial compatibilizer. The structural and morphological changes of the composite films were studied using Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), thermal gravimetric analysis (TGA), and scanning electron microscopy (SEM). Despite the use of LNPs (poorly degradable in aquatic conditions) and the composite films' hydrophobicity, the presence of up to 25 wt% PCL and 5wt% LNPs did not prevent the composites from achieving > 85% biodegradation within 42 days, in both fresh water and seawater conditions. The incorporation of CNFs increased the water uptake capability of PCL which helped to increase the films' porosity, in turn enhancing the film degradation process. This study confirmed that hydrophobizing nanocellulose with biodegradable polyesters and LNPs can preserve the nanocellulose's inherent coveted biodegradability. Hence, this sustainable approach to developing bio-based composites supports responsible material development, disposal, and end-of-life management. [ABSTRACT FROM AUTHOR]

Silica aerogel materials exhibit exceptional properties, including unique light, heat, fluid, and ion characteristics with vast potential. Despite similarities in composition to glass, silica aerogel lacks ductility and is prone to breakage upon impact. Therefore, the development of advanced engineering aerogel ultra materials that combine the mechanical strength of engineered materials with the ultralight superinsulation of aerogels remains a significant challenge. Herein, a multidimensional and multiscale gradient‐pore strategy is proposed for the scalable production of nanostructured silanized cellulose (SiCell) nanofibrous frameworks through colloidal self‐assembly using an active earth‐abundant biopolymer from the wood as a functional component. The configuration of the SiCell/polymer‐crosslinked silica‐aerogel‐powder (SiAP)‐locked structure creates a regional framework that forms SiCell/polymer‐crosslinked SiAP‐locked aerogels (SiCSiPA) with a 3D nanoporous architecture. With an ultralow thermal conductivity of 15.9 mW m−1 K−1, the lightweight super insulating SiCSiPA emerges as a prime candidate for thermal insulation, offering exceptional strength for practical applications. Moreover, SiCSiPA exhibits superior strength, stiffness, and toughness, making it the best insulating material. Owing to its outstanding strength‐to‐weight ratio and robust thermomechanical stability, SiCSiPA introduces a new technology for lightweight construction applications requiring superior thermal insulation. [ABSTRACT FROM AUTHOR]

In this article, polyether‐modified polysiloxanes were synthesized by the reaction of poly(methyl hydrogen siloxane) (PMHS) with Allyl alcohol polyether B‐400. FT‐IR, laser particle size analysis, hydrophilic–lipophilic balance (HLB) value test, and surface tension measurements were used to characterize its structures and properties. The results show that the control law for the HLB value of polyether‐modified polysiloxanes was obtained as follow: the HLB value increases with increasing hydrogen content of PMHS. When the polyether‐modified polysiloxanes were used to emulsify the polysiloxane, at the HLB value of 10.5, the average particle size of the emulsion was about 0.23 μm with a narrow particle size distribution. The emulsion has good emulsifying and dispersing properties, as well as excellent foam elimination and foam inhibition performance. When the cellulose nanofibrils (CNF) was used as a protective agent for the preparing of the polysiloxane defoamer, the stability of the emulsion does not affect, but its foam elimination and foam inhibition of emulsion can be further improved at the presence of CNF. The lowest surface tension of CNF‐enhanced polyether‐modified polysiloxane defoamer is about 22.4 mN m−1, which has good surface property. When the concentration of CNF‐enhanced polyether‐modified polysiloxane defoamer was 0.1 g L−1, the foam elimination time and foam inhibition time were 5.8 s and 38 min, respectively, at the temperature (80°C) and alkali environment (pH 13). [ABSTRACT FROM AUTHOR]

Boron nitride nanosheets (BNNSs)-cellulose nanofibrils (CNF) nanocomposites have attracted significant interest as advanced materials for thermal management. However, their thermal conductivities are still insufficient due to the high interfacial thermal resistances (ITR) among the different components of the composites. In the present work, copper nanoparticles (CuNPs)-BNNS (Cu-BNNS) hybrid fillers were prepared by anchoring CuNPs on the BNNS surfaces using the liquid phase reduction method. Subsequently, the hybrid fillers were dispersed in a CNF matrix to produce the Cu-BNNS/CNF composite film, which exhibited high in-plane and out-of-plane thermal conductivities up to 37.5 ± 3.1 and 1.8 ± 0.026 W·m–1·K–1, respectively. The copper nanoparticles connecting the adjacent BNNSs contributed to reduced ITR and significant improvement of thermal conductivity. Specifically, CuNPs did not compromise the electrical insulation of the BNNS/CNF composites when enhancing their heat dissipation capability. The Foygel model developed for Cu-BNNS/CNF theoretically confirmed the role of copper nanoparticles. This study provides a feasible strategy for advancing the applications of BNNS and CNF in modern electronics for sustainable thermal management. [ABSTRACT FROM AUTHOR]

Over the last years, the potential of cellulose nanocrystals (CNCs) and cellulose nanofibrils (CNFs) as fillers in polymers for mechanical reinforcement and extending the operation lifespan of materials is highlighted. Here, we investigate the inclusion of CNCs and CNFs with two distinct functional groups (TEMPO-oxidized, or solely having hydroxyl groups) as nanofillers into cellulose acetate films. Solution blow spinning has been utilized as a novel approach to fabricate composite materials from renewable carbon feedstocks, and the resulting structural, morphological and mechanical properties were evaluated. A maximum concentration of 5 wt% was found for CNCs while this was lower for CNFs, 2.5 wt%, to achieve uninterrupted processing of composite materials via SBS. All-cellulose composites showed differences in morphological features depending on the nanofiller type. Interestingly, a low loading of CNCs (1.5 wt%) increases the strength at break by 30%, while the inclusion of CNFs in a same amount deteriorates the mechanical properties. However, further increase to 2.5 wt% CNFs provides enhanced tensile strength and elastic modulus values. The largest improvements in elongation at break and strength at break is achieved with the inclusion of 2.5 wt% TEMPO-oxidized cellulose nanofibrils. Microscopic analysis after fracture reveals coral-like structured films, providing a unique mechanical behavior. Overall, the results point out that TEMPO-oxidized CNFs are efficient reinforcements to fabricate renewable carbon-containing composite materials with improved mechanical performance. The proposed SBS processing offers a unique advantage in the fabrication of highly flexible cellulose-based films, eliminating the need for plasticizers or additional additives. [ABSTRACT FROM AUTHOR]

Cellulose nanofibrils are distinguished bionanomaterials known for their unique morphology, thermal stability, and ability to form networks, yet they encounter challenges in compatibility with hydrophobic matrices, limiting their application in various applications. This study introduces an innovative surface modification method to address the high hydrophilicity of CNFs. The novelty lies in the use of lipase as a biocatalyst in combination with renewable grafting agents, specifically butanoic and oleic acids. The lipase successfully esterified both acids onto the CNFs, with butanoic acid exhibiting a higher surface concentration, resulting in a more substantial reduction in hydrophilicity. Contact angle measurements demonstrated a notable shift, from 10.84° for untreated CNF to 68.4° and 55.1° for CNFs grafted with butanoic and oleic acid residues, respectively. While there were only slight alterations in crystallinity, thermal stability, and brittleness, lipase proved to be an effective catalyst for modifying the CNF surface with fatty acids. This approach offers a method to mitigate the high hydrophilicity of CNFs without compromising their key properties. Furthermore, it can be proposed as a means to tailor CNF for water-resistant applications in fields such as electronics, packaging, and Pickering emulsions. The structure of the lipase protein was sourced from the Protein Data Bank (PDB), first referenced by Xie et al. [38] [ABSTRACT FROM AUTHOR]

Nanocellulose has emerged as a widely utilized building block in nanostructured materials due to its availability, sustainability, large surface area, and high stiffness and aspect ratio. The wet or dry elastoplastic properties of these materials are determined by the fibrils' stiffness, chemical properties, hemicellulose content, and the number of fibril contacts. However, the specific contributions and relative importance of each factor remain unclear. Therefore, this work was devoted to systematically comparing the material properties of gels, aerogels, and wet and dry sheets prepared from CNFs with different aspect ratios, chemical functionality, and hemicellulose content. The fibrils were prepared by chemical and mechanical processing of different pulps. By preserving the native structure as much as possible, higher aspect ratio fibrils can be obtained, which allows for the development of more mechanically robust materials. The results demonstrate that higher aspect ratios lead to more interconnected networks at a lower solids concentration, resulting in a more evenly distributed stress and longer-range stress transfer, yielding stiffer and more ductile materials. The most important finding was that the aspect ratio influences the network formation, resulting in different network topologies. The results were also compared to earlier published data and integrated into a theoretical beam-bending model for a complete elastoplastic description of the network properties, including the influence of fibril aspect ratio and chemical functionality. This information improves our understanding and description of nanofibril networks for which general models have been missing. It can be used to optimize nanofibril preparation and, hence, the resulting eco-friendly materials. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry 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.)

Industrial residues that are not optimally utilized are removed by burning, landfilling, or dumping, which can threaten the environment and health. In fact, part of this agro-industrial waste still has content that has the potential to become raw material for value-added other industries. Dates by-product as residue of the fiber-rich fruit industry have the potential to be a source of nanocellulose. This study aims to obtain nanofibril cellulose (CNF) isolates from dates by-product via citric acid hydrolysis, and investigate the effect of acid concentration on the unknown dates by-product CNF isolate characteristics. Pretreatment such as delignification and bleaching is needed to obtain cellulose isolate with high purity. Furthermore, acid hydrolysis, centrifugation, and sonication are performed to obtain CNF. CNF isolates are characterized by the analysis of particle size distribution, morphology, and crystallinity. Analysis of functional groups and lignocellulose content test confirm that lignin and hemicellulose are degraded during isolation. The particle size distribution measurement shows that the greater the acid concentration, the smaller the CNF size and the better the size uniformity. The morphology of the CNF obtained is net-like fibers. The degree of crystallinity shown decreases with increasing acid concentration. This study revealed that different citric acid concentrations can result in different characteristics of CNF isolates.

In recent years, the extensive use of plastic packaging has caused serious environmental pollution problems. With the increase in people's environmental awareness, the development of new biodegradable food packaging materials to replace traditional petroleum-based plastics has become a hot research topic. Cellulose nanofibrils (CNF) are widely favored by researchers due to its excellent properties such as high specific surface area, elastic modulus, strength, and gas barrier properties. This paper summarizes the preparation methods of CNF and CNF composite films, discusses the mechanical property, barrier property, antibacterial property, degradable property, and responsive property as food packaging materials. Finally, the challenges faced by CNF in the field of food packaging are proposed, aiming to provide a reference for the future production of CNF food packaging materials to replace traditional petroleum-based materials.

[Display omitted] • Lignin nanoparticles bridge hydrophilic nanocellulose and hydrophobic polycaprolactone. • Lignin nanoparticles mitigate nano-scaled phase separation in composite. • Interfacial interactions in aqueous and dry states tailor composite properties. • Broadband dielectric spectroscopy reveals details about molecular dynamics. • Surface analysis elucidates interactions during composite formation. Advancing nanocomposites requires a deep understanding and careful design of nanoscale interfaces, as interfacial interactions and adhesion significantly influence the physical and mechanical properties of these materials. This study demonstrates the effectiveness of lignin nanoparticles (LNPs) as interfacial compatibilizer between hydrophilic cellulose nanofibrils (CNF) and a hydrophobic polyester, polycaprolactone (PCL). In this context, we conducted a detailed analysis of surface-to-bulk interactions in both wet and dry conditions using advanced techniques such as quartz crystal microbalance with dissipation (QCM-D), atomic force microscopy (AFM), water contact angle (WCA) measurements, broadband dielectric spectroscopy (BDS), and inverse gas chromatography (IGC). QCM-D was employed to quantify the adsorption behavior of LNPs on CNF and PCL surfaces, demonstrating LNPs' capability to interact with both hydrophilic and hydrophobic phases, thereby enhancing composite material properties. LNPs showed extensive adsorption on a CNF model film (1186 ± 178 ng.cm−2) and a lower but still significant adsorption on a PCL model film (270 ± 64 ng.cm−2). In contrast, CNF adsorption on a PCL model film was the lowest, with a sensed mass of only 136 ± 35 ng.cm−2. These findings were further supported by comparing the morphology and wettability of the films before and after adsorption, using AFM and WCA analyses. Then, to gain insights into the molecular-level interactions and molecular mobility within the composite in dry state, BDS was employed. The BDS results showed that LNPs improved the dispersion of PCL within the CNF network. To further investigate the impact of LNPs on the composites' interfacial properties, IGC was employed. This analysis showed that the composite films containing LNPs exhibited lower surface energy compared to those composed of only CNF and PCL. The presence of LNPs likely reduced the availability of surface hydroxyl groups, thus modifying the physicochemical properties of the interface. These changes were particularly evident in the heterogeneity of the surface energy profile, indicating that LNPs significantly altered the interfacial characteristics of the composite materials. Overall, these findings emphasize the necessity to control the interfaces between components for next-generation nanocomposite materials across diverse applications. [ABSTRACT FROM AUTHOR]

[Display omitted] Despite significant research into cellulose nanofibril (CNF) films as substitutes to synthetic plastic materials, commercial applications remain very limited. One major hindrance is the poor water vapor barrier properties of CNF films compared to polyolefins, a critical property for product protection, such as food safety and preservation. To date, it is unknown whether full moisture barrier properties can be achieved with materials made by the assembly of nanofibers and fibrils. A comprehensive understanding of the effect of film structure on water vapor transport properties is required. Here, over 200 films were produced with a wide range of grammages from 30 g/m2 to 580 g/m2 by casting and spray deposition. Their structures were quantified by µCT and SEM and related to their water vapor transmission rates (WVTRs). Porosity and pore connectivity decreased with increasing film grammage, which correlates with the exponential decrease in WVTR. However, the WVTR plateaued at 30 g/m2day, indicating that the known open space and adsorption diffusion mechanisms cannot be fully eliminated by producing high grammage films. Pure cellulose nanofibril films therefore cannot replace polyolefins in packaging applications, requiring modifications such as coating and nanofillers. [ABSTRACT FROM AUTHOR]

This study is centered on improving the mechanical and barrier characteristics of cellulose nanofibril films for food packaging applications. The goal was to induce fibril orientation, which was achieved by fabricating CNF films via an auto-dynamic sheet former (ADSF) at varying wire speeds, and varying CNF suspension solid contents. The wet-laid films were then dried using restrained (Z_Z shrinkage) and non-restrained (XY_Z) methods. Z_Z films demonstrated higher strength compared to XY_Z films at wire speeds of 1000 m/min and 1100 m/min. Films produced at 1100 m/min demonstrated the best oxygen barrier properties, irrespective of the drying technique employed. For 1100 m/min 0.1 wt.% films, the oxygen permeability values were decreased by 51.7% for the Z_Z shrinkage drying method and 40.3% for the XY_Z shrinkage drying method when compared to 900 m/min 0.1 wt.% films. The orientation of the film was assessed using polarized light microscopy (PLM) and wide-angle X-ray scattering (WAXS). However, these methods seemed to be limited to specific instances, as only a small area of the film could be imaged which did not provide a comprehensive indication of the overall alignment of the film, likely due to averaging of film's response to these techniques caused by their multi-layer structure. Future research could delve deeper into producing oxygen barrier packaging materials using similar formulations in a paper-forming machine. Additionally, a potential future study could explore depositing an aligned CNF layer directly onto the paper substrate to form sustainable food containers made of paper. [ABSTRACT FROM AUTHOR]

Micro- and nano-scale cellulosic fillers exhibit excellent dispersion and distribution within a thermoplastic matrix during the process of melt compounding or injection molding. In this study, spray-dried cellulose nanofiber (SDCNF) powders were manufactured using a pilot-scale rotating disk atomizer spray dryer. Bleached Kraft pulp (BKP), unbleached Kraft pulp (UKP), and old corrugated cardboard pulp (OCC) fibrillated at a fines level of 90% were used as feedstock materials for spray-drying. BKP-, UKP-, and OCC- SDCNFs were compounded with polypropylene using a twin screw co-rotating extruder. Maleic anhydride grafted polypropylene (MAPP) was used as a coupling agent in the composite formulations. The tensile, flexural, and impact properties of SDCNF-filled PP composites increased at 10 wt% SDCNF loading. The presence of SDCNFs in the PP matrix resulted in faster crystallization and a 12% reduction in the degree of crystallinity of the neat PP. The coefficient of thermal expansion (CTE) of neat PP was reduced by up to 31% attributable to the presence of the SDCNFs. Application of the SDCNF-reinforced PP composites in 3D printing reduced the shrinkage rate of the printed neat PP by 39%, and the printability of the PP was significantly improved with the addition of the SDCNFs. [ABSTRACT FROM AUTHOR]

Light‐emitting diodes (LEDs) are widely used in lighting and display applications. Carbon quantum dots (CQDs), which have high biocompatibility, high resistance to photobleaching, and full‐spectrum luminescence, have inherent advantages as fluorescent materials for LED devices. Herein, multicolor CQDs are prepared by a new reagent engineering strategy due to the difference of effective conjugate length and the surface electron‐withdrawing groups of CQDs. White CQDs are realized by mixing blue, green, and red CQDs proportionally. Then, the aggregation‐caused quenching phenomenon of CQDs is suppressed through the hydrogen‐bonding network of cellulose nanofibrils (CNFs). Multicolor fluorescent films are prepared from CQDs and CNFs by simple mixing and casting methods. Finally, thin‐film encapsulation based on the photosensitive resin ABPE‐10 coating can be realized and rapidly assembles into fluorescent films with different light‐emitting colors into LED devices, leading to have superior thermal performance compared with conventional LEDs. White LEDs have excellent white‐light illumination performance, with Commission Internationale de L'Eclairage color coordinates of (0.33, 0.37), a correlated color temperature of 5688 K, and a color rendering index of 86. This strategy provides a convenient and scalable pathway for low‐cost, environmentally friendly, and high‐performance CQDs‐based LEDs. [ABSTRACT FROM AUTHOR]

With the increasing global demand for net-zero carbon emissions, actions to address climate change have gained momentum among policymakers and the public. The urgent need for a sustainable economy is underscored by the mounting waste crisis in landfills and oceans. However, the proliferation of distributed electronic devices poses a significant challenge due to the resulting electronic waste. To combat this issue, the development of sustainable and environmentally friendly materials for these devices is imperative. Cellulose, an abundant and CO2-neutral substance with a long history of diverse applications, holds great potential. By integrating electrically interactive components with cellulosic materials, innovative biobased composites have been created, enabling the fabrication of bulk electroactive paper and the establishment of new, potentially more sustainable manufacturing processes for electronic devices. This review explores recent advances in bulk electroactive paper, including the fundamental interactions between its constituents, manufacturing techniques, and large-scale applications in the field of electronics. Furthermore, it addresses the importance and challenges of scaling up production of electroactive paper, highlighting the need for further research and development. [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.)

In this study, the impact of incorporating cellulose nanofibrils (CNF) and carboxylated organo‐montmorillonite (OMMT), separately or in combination, into a UV‐curable wood coating was evaluated for performance enhancement. This study investigated the influence of nanoparticle loading percentage on the mechanical properties and thermal behavior of the coating, as well as the surface properties of digitally printed decorative wood‐based panels. The results indicated that the addition of CNF or OMMT increased the viscosity of the polymer solutions. Although CNF randomly oriented within the matrices, OMMT adhered to the surface of the polymer matrix. Chemical crosslinking was observed between CNF/OMMT and the coating. The addition of CNF and OMMT improved the thermal stability of the neat UV curing coating. The tensile strength of nanocomposite films with a 6 wt% loading of CNF increased significantly from 7.63 MPa to 12.73 MPa compared to pure films. The reinforcing effect of CNF on the tensile performance was significantly better than that of OMMT. Adding CNF to the matte coating slightly improved the clarity of the printed decorative panels. When CNF and OMMT were added together in the coating, there was a synergistic enhancement in the low gloss and high pencil hardness of the panels. Highlights: Both CNF and OMMT were chosen to achieve performance improvementsA simple filling method was adopted for preparation of reinforced coatingThe nanocomposite films exhibited fine thermal and mechanical propertiesThe better integrated property was obtained from the C + CNF3 + OMMT0.8 sampleThe physicochemical interaction of nanofiller with polymer molecule existed [ABSTRACT FROM AUTHOR]

The rechargeable zinc‐ion battery is regarded as a promising candidate for the next‐generation energy storage system, however, zinc dendrite growth and hydrogen evolution reaction (HER) have greatly hindered the practical application of the battery. Herein, a functionalized, nano‐engineering Zn2+ coordinated carboxylate cellulose solid‐state electrolyte (denoted as Zn‐CCNF@XG) for zinc‐ion battery is constructed through a straightforward approach. According to the experimental and density functional theory (DFT) results of dissociation energy, the notably decreased dissociation energy by −COOH is favorable to Zn2+ de‐coordinating and rapid ion‐hopping in Zn‐CCNF@XG to achieve high ionic conductivity and transference number. More importantly, the engineered molecular channels are beneficial to enlarging the distance between the nanofibril chains, providing a larger space for the movement of Zn2+. Benefiting from the coordination of Zn2+ with −OH in carboxylate cellulose nanofibrils, Zn‐CCNF@XG as a good ionic conductor displays a high ionic conductivity of 1.17 × 10−4 S cm−1 and transference number of 0.78. The Zn||NaV3O8·1.5H2O full cell with Zn‐CCNF@XG maintains a capacity retention of 83.46% with a coulombic efficiency of 99.99% after 3000 cycles (1 A g−1). The proposed strategy by introducing a functional group to cellulose nanofibrils effectively avoids the dendrite and HER, providing valuable guidelines for the practical application of zinc‐ion batteries. [ABSTRACT FROM AUTHOR]

Cellulose nanofibrils/poly(N-Isopropylacrylamide) semi-interpenetrating networks (MMCNF-PNAs) were synthesized using an in situ fabrication (semi-IPN). The polymerization of N-isopropylacrylamide (NIPAM) (free radical) was conducted in the presence of magnetic modified cellulose nanofibrils (MMCNFs). The adsorption behaviors and surface morphology of the synthesized adsorbents were investigated systematically. The adsorption behaviors of the as-prepared MMCNF-PNA towards methylene blue (MB, as the model contaminant) dye was studied, and the optimal adsorption conditions were also studied. The adsorption processes could be well fitted using pseudo-second-order and Elovich kinetic models. Meanwhile, Langmuir and Freundlich isotherm models were used to fit the adsorption which occurred at 25, 37 and 65 °C. The corresponding results showed that the Freundlich isotherm model fitted the adsorption process better, indicating that the dye's adsorption happened via heterogeneous adsorptive energies on the prepared MMCNF-PNAs. Their desorption and reusability were also studied to verify magnetic responsivity. To sum up, MMCNF-PNAs are promising magnetic and thermal stimuli-responsive adsorbents, showing a controlled adsorption/desorption process. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has brought concerns about the efficacy of respiratory protection equipment, primarily due to their widespread usage during this period. Among the various types of face masks, the N95, PFF3, and PFF2 surgical masks have gained great prominence due to their efficiency, despite the discomfort they may cause. Therefore, thinking of a cost-effective and more comfortable solution, this work aimed to reinforce non-woven face masks with cellulose nanofibrils (CNFs), to improve their filtration efficiency. For this, CNFs were produced using the mechanical processing of sugarcane bagasse (SCB) residues, which underwent plain alkaline pretreatment (CNF-PA) or alkaline pretreatment followed by enzymatic pretreatment (CNF-AE). It was observed that the CNF-AE films developed better characteristics regarding the contact angle, density, porosity, transmittance and transparency as well as vapor permeability compared to the CNF-PA films. The application of CNF on non-woven masks was performed using the spray technique. Bacterial filtration analysis showed filtration efficiency of 99.68% and 99.80% for masks that were coated with CNF-PA and CNF-AE, respectively. Whereas uncoated masks presented a filtration efficiency below 95%, which is the minimum required value. The masks obtained breathability values of 79.75 Pa/cm2 and 106.00 Pa/cm2 for CNF-AE and CNF-PA, respectively, whereas the uncoated masks showed values below 30.00 Pa/cm2. This work shows that the CNF obtained from SCB present good barrier capabilities and should be used for this purpose, especially on protective masks.

Japanese papers (JPs) are among the most common materials used for the restoration of historical papers. However, they have low transparency and may structure the paper surface. To overcome the limitations of JPs, in the present work films of cellulose nanofibers with and without lignin (LCNFs and CNFs, respectively) were explored. For this, chemically different LCNFs (carboxylated by TEMPO-mediated oxidation using variable oxidant amount and sulfated with deep eutectic solvent) and two reference CNFs were produced from Eucalyptus kraft pulps. Lignin slightly hindered the introduction of carboxyl groups into the cellulose structure, but did not affect the incorporation of sulfate groups. (L)CNFs gave films with better mechanical properties than those determined for three types of JP (tensile strength of 79–142 MPa (±11) vs 3.5–13.0 MPa (±0.4) and Young's modulus of 4900–5900 MPa (±300) vs 240–1800 MPa (±70)). Additionally, the (L)CNF films exhibited lower water vapor transmission rates (132–312 g.m−2.day−1) compared to the JPs (685–719 g.m−2.day−1), and a higher transparency (up to 89% and ≤82% for JPs). Except for the thermal stability, all properties studied favored (L)CNF films over JPs, indicating their strong potential for restoration/conservation applications. This systematic comparison between the properties of (L)CNF films and JPs has never been conducted before.

One-pot syntheses and in situ ultrasonication have been optimized to generate tunable and highly hydrophobic 2,7-octadienyl-ether (ODE) cellulose nanofibrils (CNFs). Using only butadiene sulfone to serve as dual reaction medium and precursor to 1,3-butadiene (1,3-BD) for telomerization with cellulose hydroxyls, the OH-to-ODE conversion significantly improved from ca. 0.7 to 1.2, 1.8, 3.1, and 4.1 mmol of ODE/g-cellulose at 103-110 °C for 1-2 h. Ultrasonication was highly effective and versatile in the direct disintegration of ODE-cellulose (ODE-cell) in nonpolar organic solvents and plant oils into ODE-CNFs as well as pretreating cellulose for improved functionalization. Mixing 2 wt % in situ ultrasonicated 1.2 mmol of ODE/g-cell improved the modulus of polybutadiene six times and the strength of poly(styrene-b-isoprene-b-styrene) three times, whereas in situ ultrasonication of 1.8 mmol/g-cell directly with linseed oil at merely 0.07 wt % created holistic biobased hydrophobic cellulose paper to resist water penetration while also significantly improving the tensile strength. This optimized telomerization and streamlined in situ ultrasonication approach has presented a sustainable synthesis and processing strategy to generate highly hydrocarbon-compatible nanocelluloses previously unattainable.

With downward pressure on the value of almond hulls (AHs), the major byproduct from the largest tree nut crop globally, the streamlined production of several grades of cellulose nanofibrils (CNFs) toward novel aerogels with concurrent sugar extraction was introduced to synergistically drive these products toward commercial adoption. Hot water extraction produced 50% lignocellulose (LC) with equal water-soluble sugars from AH of a soft-shell variety. Aqueous NaOH and NaClO2/KOH treatments isolated ca. 15% alkali cellulose and 12% cellulose, respectively. Coupled 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) oxidation and blending yielded 88, 91, and 95% LC micro-/nanofibrils (LCMNFs), alkali cellulose nanofibrils (ACNFs), and cellulose nanofibrils (CNFs) with, respectively, 0.76, 1.02, and 0.84 mmol/g surface carboxyls in a similar 4:1 width-to-thickness aspect ratio and ultrahigh length-to-thickness aspect ratios (800-1900). The LCMNF aerogel was mostly wet-resilient, wet-stable, and dry/wet shape-recoverable, whereas the most charged ACNFs gave the stiffest aerogel [31.6 kPa/(mg/cm3)].

The colloidal layer formation on porous materials is a crucial step for printing and applying functional coatings, which can be used to fabricate anticounterfeiting paper. The deposition of colloidal layers and subsequent thermal treatment allows for modifying the hydrophilicity of the surface of a material. In the present work, wood-based colloidal inks are applied by spray deposition on spray-deposited porous cellulose nanofibrils (CNF) films. The surface modification by thermal annealing of the fabricated colloid-cellulose hybrid thin films is investigated in terms of layering and hydrophobicity. The polymer colloids in the inks are core–shell nanoparticles with different sizes and glass transition temperatures (Tg), thus enabling different and low thermal treatment temperatures. The ratio between the core polymers, poly-(sobrerol methacrylate) (PSobMA), and poly-(-butyl methacrylate) (PBMA) determines the Tg and hence allows for tailoring of the Tg. The layer formation of the colloidal inks on the porous CNF layer depends on the imbibition properties of the CNF layer which is determined by their morphology. The water adhesion of the CNF layer decreases due to the deposition of the colloids and thermal treatment except for the colloids with a size smaller than the void size of the porous CNF film. In this case, the colloids are imbibed into the CNF layer when Tg of the colloids is reached and the polymer chains transit in a mobile phase. Tailored aggregate and nanoscale-embedded hybrid structures are achieved depending on the colloid properties. The imbibition of these colloids into the porous CNF films is verified with grazing incidence small-angle X-ray scattering. This study shows a route for tuning the nanoscale structure and macroscopic physicochemical properties useful for anticounterfeiting paper. [ABSTRACT FROM AUTHOR]

The cationic cellulose nanofibrils demonstrate outstanding properties and have garnered extensive attention as sustainable materials. However, the large-scale preparation of cationic cellulose nanofibrils was limited since the high crystallinity of plant fibers made them harder to disintegrate and nanofibrillate. In this study, cationic cellulose nanofibrils, HKCF, were produced from softwood bleached kraft pulp (SWBK) with 2,3-epoxypropyltrimethylammonium chloride (EPTAC) by disk milling, followed by high-pressure homogenization. Morphologies and structures of cationic fibers (KCF and CCF) and homogenized products were characterized. The influence of cationization combined with high mechanical shear on the degree of substitution (DS) of cationic fibers was studied. At the same molar ratios of EPTAC to anhydroglucose units and holding time, the DS of KCF was higher than that of CCF. Compared with simple mixing induced by conventional stirring, the high mechanical shear induced by disk milling could increase the cationic efficiency of EPTAC by at least 50%. After high-pressure homogenization, KCF was completely fibrillated to HKCF with nano-scaled dimensions. HKCF dispersion showed a Bingham flow behavior and viscosity-dominating fluid-like behavior. Our study provides a facile and effective industrialized approach for producing highly substituted cationic cellulose nanofibrils. [ABSTRACT FROM AUTHOR]

Extracellular vesicles (EVs), crucial in facilitating the transport of diverse molecular cargoes for intercellular communication, have shown great potential in diagnostics, therapeutics, and drug delivery. The challenge of developing effective preparation methods for EVs is heightened by their intrinsic heterogeneity and complexity. Here, a novel strategy for high EV enrichment is developed by utilizing EV‐affinitive‐modified cellulose nanofibrils. Specifically, modified cellulose with rich carboxyl groups has outstanding dispersing properties, able to be dispersed into cellulose nanofibrils in solution. These cellulose nanofibrils are utilized as scaffolds for the immobilization of EV‐affinitive antibody of CD63 by chemical conjugation. The CD63‐modified nanofibrils demonstrate a superior EV capture efficiency of 86.4% compared with other reported methods. The high performance of this system is further validated by the efficient capture of EVs from biological blood plasma, allowing the detection of bioactive markers from EV‐derived miRNAs and proteins. The authors envision that these modified cellulose nanofibrils of enhanced capability on EV enrichment will open new avenues in various biomedical applications. [ABSTRACT FROM AUTHOR]

Low-cost lignocellulosic filters were made from soybean hulls (SH), sugarcane bagasse fibers (SBF), cellulose nanofibers (CNF), and Kraft-bleached pulp (BP) as renewable feedstocks and applied in Cu (II) and Cd (II) removal from aqueous medium. Filtration was performed with a vacuum pump; filtration times ranged from 3 to 1200 seconds. For the same filter, the best permeate flow was 13,333 L.h.m-2 for both cations. The best Cd (II) removal (77.2 %) was achieved within 7 seconds at a permeate flow of 5,714 L.h.m-2. The same filter was also the best at removing Cu (II) (46.5 %), which was achieved within 7 seconds at a permeate flow of 5,714 L.h.m-2, as well. This short time evidenced that a long contact time is not needed to achieve higher removal. The best filter was made of BP, CNF, and SH. The presence of SBF and SH increased the contact angle and decreased the solid free energy surface. By FTIR-ATR it was possible to verify with which groups present in the chemical structures of the filter components the Cd (II) and Cu (II) cations interacted best. These results demonstrate the potential use of lignocellulosic biomass for producing composites aimed at water decontamination. [ABSTRACT FROM AUTHOR]

A high content of water is needed in traditional thermoplastic starch (TPS) processing to plasticize the starch and facilitate the processing, which leads to relatively low strength and modulus of the products and causes the issue of product aging partially due to the gradual water loss over time. In this work, based on the results from our previous study on lignin and cellulose nanofibril-reinforced TPS composites, a low content of citric acid (<0.5 wt%) was used to replace all the added water in the prior study (∼20 wt%). Citric acid demonstrated a much stronger viscosity-reducing effect than water and enabled composite processing at a very low acid content. The resultant nanocomposites exhibited much higher strength and modulus than those containing 20 wt% water as the processing aid. Fourier transform infrared spectrometry (FTIR) results showed strong interactions between the polar groups of starch and other ingredients. Scanning electron microscopy (SEM) photos indicated the disappearance of the two-phase "sea-island" morphology, suggesting the strong compatibilization effect of the acid. To lower the cost of the nanocomposites, we further replaced the starch and zein (an expensive biopolymer) components in the original composites with low-cost cornmeal. The new nanocomposites with cornmeal as the major ingredient exhibited similar processability and mechanical properties. With its low cost and high properties, this new type of agricultural byproduct-based nanocomposites is expected to be a promising material to replace synthetic polymers in many applications. [ABSTRACT FROM AUTHOR]

Pickering multiphase systems stabilized by solid particles have recently attracted increasing attention due to their excellent stability. Among various solid stabilizers, natural and renewable cellulosic micro/nanoparticles that are derived from agricultural and forestry sources have become promising candidates for Pickering stabilization due to their unique morphological features and tunable surface properties. In this review, recent progress on forming and stabilizing Pickering multiphase systems using cellulosic colloidal particles is summarized, including the physicochemical factors affecting their assembly at the interfaces and the preparation methods suitable for producing Pickering emulsions. In addition, relevant application prospects of corresponding Pickering multiphase materials are outlined. Finally, current challenges and future perspectives of such renewable Pickering multiphase systems are presented. This review aims to encourage the utilization of cellulosic micro/nanoparticles as key components in the development of Pickering systems, leading to enhanced performance and unique functionalities. [ABSTRACT FROM AUTHOR]

Pretreatment of pulp is a critical step in the fibrillation process to improve the quality and efficiency for cellulose nanofibril (CNF) production. This work employed a straightforward and entirely aqueous methacrylation and subsequent grafting-through polymerization technique to modify bleached softwood kraft pulp (BSKP). Specifically, methacrylate groups, poly(acrylamide) (PAM), and poly(methyl methacrylate) (PMMA) were chemically affixed to the surface of BSKP fibers, which was confirmed using FTIR spectroscopy. Bench-scale experiments were scaled up to pilot scale to prepare the modified BSKP samples, these were subjected to fibrillation using a Supermasscolloider (SMC), and the net cumulative energy (NCE) expended was monitored during the fibrillation process. Notably, the modified BSKP samples exhibited a substantial reduction in NCE, with the methacrylate modified BSKP sample achieving a 68% reduction in NCE expenditure to attain 90% fines as compared to the fibrillation of unmodified BSKP and producing methacrylate modified cellulose nanofibrils (Met-CNFs). Furthermore, we delved into the impact of polymeric surface modifications, both pre-and post-fibrillation, on fiber and fibril behavior, including the water retention value (WRV), hard-to-remove water (HR-Water), and rheological behavior. The attached polymer's hydrophilicity and hydrophobicity influenced the physical properties of the CNFs. Additionally, we executed a post-grafting polymerization process on the produced Met-CNFs. This additional step allowed us to modify nanofibril surfaces, yielding increased surface functionalization and producing modified CNFs that could be used for composite applications. [ABSTRACT FROM AUTHOR]

In the presented research, a facile, one-step method for the fabrication of cellulose nanofibrils/pectin (CNFs/PC) membranes is described, which were tested further for their ability to remove cationic dyes from the prepared model solutions. For this purpose, ten membranes were prepared with different quantities of CNFs and PC with/without citric acid (CA) or CaCl2 as mediated crosslinking agents, and they were characterised comprehensively in terms of their physical, chemical, and hydrophilic properties. All the prepared CNFs/PC membranes were hydrophilic with a Water Contact Angle (WCA) from 51.23° (without crosslinker) up to 78.30° (CaCl2) and swelling of up to 485% (without crosslinker), up to 437% (CaCl2) and up to 270% (CA). The stability of membranes was decreased with the increase in PC; thus, only four membranes (M1, M2, M3 and M5) were stable enough in water after 24 h, and these were additionally applied in the adsorption trials, using two structurally different cationic dyes, i.e., C.I. Basic Yellow 28 (BY28) and C.I. Basic Blue 22 (BB22), in four concentrations. The highest total surface charge of M3 (2.83 mmol/g) as compared to the other membranes influenced the maximal removal efficiency of both dyes, up to 37% (BY28) and up to 71% (BB22), depending on the initial dye concentration. The final characteristics of the membranes and, consequently, the dye's absorption ability could be tuned easily by changing the ratio between the CNFs and PC, as well as the type and amount of crosslinker. [ABSTRACT FROM AUTHOR]

Cellulose nanofibrils (CNF) can be modified to be used as a coating on food paper packaging. Previous research on PVA/CNF composites showed a low viscosity, which impacted their performance on the coating paper process. To overcome this problem, a thickening agent, such as carboxymethyl cellulose (CMC), is needed. In this work, the effect of CMC on PVA/CMC/CNF nanocomposites was investigated by varying the concentrations of CMC with PVA/CMC and CNF ratio of 80:20 and 90:10. The nanocomposites were characterized by their physical and tensile properties which could affect their coating performance. Moreover, the coating process was conducted on paper and the performances of the coated paper were studied. The results showed that the increase in CMC concentration led to an increasing viscosity and good zeta potential, suggesting good dispersion. Moreover, the addition of CMC improved the tensile properties of PVA/CMC/CNF nanocomposites. However, SEM analysis of PVA/CMC-1:CNF (80:20) revealed the occurrence of agglomeration which might influence the performance of the coated paper. Interestingly, PVA/CMC-1:CNF (80:20) had an excellent water resistance, with the lowest Cobb60. Moreover, the addition of CMC 1 wt% increased WVTR, which remained lower than the blank sample. Meanwhile, PVA/CMC-2:CNF (80:20) demonstrated the best performance in the oil absorption and tearing resistance test. In summary, the addition of CMC can effectively improve the physical and tensile properties of the PVA/CMC/CNF, as well as the barrier properties and tear strength of the PVA/CMC/CNF coated paper. The results demonstrate the potency of this material as a coating for food packaging paper. [ABSTRACT FROM AUTHOR]

Light‐emitting diodes (LEDs) are widely used in lighting and display applications. Carbon quantum dots (CQDs), which have high biocompatibility, high resistance to photobleaching, and full‐spectrum luminescence, have inherent advantages as fluorescent materials for LED devices. Herein, multicolor CQDs are prepared by a new reagent engineering strategy due to the difference of effective conjugate length and the surface electron‐withdrawing groups of CQDs. White CQDs are realized by mixing blue, green, and red CQDs proportionally. Then, the aggregation‐caused quenching phenomenon of CQDs is suppressed through the hydrogen‐bonding network of cellulose nanofibrils (CNFs). Multicolor fluorescent films are prepared from CQDs and CNFs by simple mixing and casting methods. Finally, thin‐film encapsulation based on the photosensitive resin ABPE‐10 coating can be realized and rapidly assembles into fluorescent films with different light‐emitting colors into LED devices, leading to have superior thermal performance compared with conventional LEDs. White LEDs have excellent white‐light illumination performance, with Commission Internationale de L’Eclairage color coordinates of (0.33, 0.37), a correlated color temperature of 5688 K, and a color rendering index of 86. This strategy provides a convenient and scalable pathway for low‐cost, environmentally friendly, and high‐performance CQDs‐based LEDs.

Low-cost lignocellulosic filters were made from soybean hulls (SH), sugarcane bagasse fibers (SBF), cellulose nanofibers (CNF), and Kraft-bleached pulp (BP) as renewable feedstocks and applied in Cu (II) and Cd (II) removal from aqueous medium. Filtration was performed with a vacuum pump; filtration times ranged from 3 to 1200 seconds. For the same filter, the best permeate flow was 13,333 L.h.m-2 for both cations. The best Cd (II) removal (77.2 %) was achieved within 7 seconds at a permeate flow of 5,714 L.h.m-2. The same filter was also the best at removing Cu (II) (46.5 %), which was achieved within 7 seconds at a permeate flow of 5,714 L.h.m-2, as well. This short time evidenced that a long contact time is not needed to achieve higher removal. The best filter was made of BP, CNF, and SH. The presence of SBF and SH increased the contact angle and decreased the solid free energy surface. By FTIR-ATR it was possible to verify with which groups present in the chemical structures of the filter components the Cd (II) and Cu (II) cations interacted best. These results demonstrate the potential use of lignocellulosic biomass for producing composites aimed at water decontamination.

The recent FDA decision to eliminate animal testing requirements emphasises the role of cell models, such as spheroids, as regulatory test alternatives for investigations of cellular behaviour, drug responses, and disease modelling. The influence of environment on spheroid formation are incompletely understood, leading to uncertainty in matrix selection for scaffold-based 3D culture. This study uses atomic force microscopy-based techniques to quantify cell adhesion to Matrigel and cellulose nanofibrils (CNF), and cell-cell adhesion forces, and their role in spheroid formation of hepatocellular carcinoma (HepG2) and induced pluripotent stem cells (iPS(IMR90)-4). Results showed different cell behaviour in CNF and Matrigel cultures. Both cell lines formed compact spheroids in CNF but loose cell aggregates in Matrigel. Interestingly, the type of cell adhesion protein, and not the bond strength, appeared to be a key factor in the formation of compact spheroids. The gene expression of E- and N-cadherins, proteins on cell membrane responsible for cell-cell interactions, was increased in CNF culture, leading to formation of compact spheroids while Matrigel culture induced integrin-laminin binding and downregulated E-cadherin expression, resulting in looser cell aggregates. These findings enhance our understanding of cell-biomaterial interactions in 3D cultures and offer insights for improved 3D cell models, culture biomaterials, and applications in drug research.

2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO) and its derivatives are well-established catalysts for various oxidation processes, despite its hazardous nature, causing harm to aquatic ecosystems. Thus, the reuse of TEMPO with a sustained high activity has gained significant importance for its industrial application, which has led to the development of supported TEMPO catalyst. In this context, the efficiency of the support process acquires high relevance. Therefore, this research is aimed at the improvement of the TEMPO supported on silica magnetically modified with Fe3O4 through the application of an online Fourier transform infrared spectroscopy (FTIR) probe to monitor its synthesis. FTIR effectively controlled the synthesis of supported TEMPO, by tracking online the concentration of 3-aminopropyltriethoxysilane (APTES) and tetraethyl orthosilicate (TEOS). Additionally, the presence of Fe3O4 particles in the core of the catalyst allowed its convenient recovery and subsequent reuse. Furthermore, the supported TEMPO catalyst was successfully applied in the oxidation of cellulose to produce nano/microfibrils. The carboxyl groups of the initial untreated cellulose increase from 0.05 mmol/g to 0.68 mmol/g with the supported TEMPO catalyst in presence of sodium hypochlorite and sodium bromide at 50 °C.

This study assessed the effects of cellulose nanofibrils (CNFs) and multi-walled carbon nanotubes (MWCNTs) on lung inflammation in a cigarette smoke-induced chronic obstructive pulmonary disease (COPD) mouse model. Prior to instillation, COPD model mice displayed distinctive cellular compositions and elevated cytokine levels in bronchoalveolar lavage fluid (BALF). After intratracheal instillation of 80 μg CNFs, no significant histopathological changes, BALF composition alterations, or cytokine level shifts were observed on day 28. This suggests minimal lung impact and no interference with reducing smoke-induced inflammation. In contrast, the instillation of 80 μg MWCNTs resulted in significant histopathological changes, increased cellular composition, and elevated cytokine levels in BALF on day 28. These findings indicate that CNF exposure had little effect on the lungs and did not impede the reduction of smoke-induced inflammation, while MWCNT exposure hindered the attenuation of pulmonary inflammatory response. The study emphasizes the importance of considering diverse cases, including individuals with pre-existing respiratory conditions, when assessing occupational safety and health risks associated with advanced nanomaterial exposure.

The continuous development of electronic devices toward high-power and integrated directions has led to an increasing demand for renewable polymer composite materials with high thermal conductivity and electrical insulation to solve the problem of overheating in electronic devices. Cellulose is inherently insulating, with insufficient thermal conductivity. Although boron nitride nanosheets (BNNSs) have excellent thermal conductivity, hexagonal boron nitride (h-BN) ligands in their raw state are prone to aggregation, which limits their performance. In this work, h-BN was first ball-milled and amino-modified, and then, carboxylated nanofibrillated cellulose (COOH-CNF) was used to disperse the BNNSs. With the help of amide bonding, the BNNSs were uniformly dispersed in the nanocellulose (CNF) matrix; this reduced the aggregation and the presence of voids between the BNNSs and promoted the construction of effective thermal channels. The resulting composite slurry was stably dispersed and could be filtered to form a film; the best overall performance was achieved for a BNNS loading of 30% with a thermal conductivity (TC) of 9.00 W·m–1·K–1 (pure CNF 1.88 W·m–1·K–1). In addition, the volume resistivity reached 9.38 × 1013 Ω·cm (pure CNF of 2.53 × 1013 Ω·cm) and the electrical strength reached 22.67 kV·mm (17.04 kV·mm for CNF). Our results showed that the BNNS-CNF composite film had high TC and excellent insulating properties; therefore, its application in the thermal management of electronic devices has broad application prospects. [ABSTRACT FROM AUTHOR]

In this study, high-purity cellulose nanofibrils (CNFs) were environmentally friendly extracted from natural bamboo. Physical, chemical, and mechanical treatments were comprehensively investigated, and then ensembled to effectively and efficiently remove lignin and hemicellulose with low energy from raw bamboo fibers, which combine microwave liquefaction, hydrogen peroxide-acetic acid delignification, alkaline treatment, and along with acid hydrolysis. This was able to allow for the extraction of CNFs. Compositional analysis, Fourier-transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and thermogravimetric analysis were performed to investigate and confirm the successful removal of undesirable lignin and hemicellulose. The resultant cellulose fibers were then subjected to a mechanical treatment to obtain the cellulose nanofibrils. It was found that the obtained CNFs have an average diameter of 13 nm with a cellulose purity of 94.52%. Without any further surface modification, the incorporation of bamboo-based CNFs into natural rubber (NR) exhibits significant improvement in their mechanical properties including modulus (~66.67%), tensile strength (~120.83%), toughness (~139.34%), and elongation at break (~31.41%). Interestingly, there is no compromise between tensile strength and elongation at break for the nanocomposites. DMA results also showed that both storage and loss moduli were dramatically enhanced over those of neat NR in their glassy region, which is typically unusual. This study can show, if optimized for material extraction, the great promise to the potential use of natural materials to develop environmentally friendly composites with multi-functionality in a variety of real-world engineering structural applications. [ABSTRACT FROM AUTHOR]

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Cellulose nanofibrils (CNFs) are ideal Pickering emulsion stabilizers, but they have limitations due to their strong hydrophilicity. In this work, modified CNFs (M-CNFs) with a water contact angle of 93.1 ± 0.6° were successfully prepared by methyl trimethoxysilane. Subsequently, the performance of the M-CNFs was characterized by crystallization performance determination (XRD), Fourier transform infrared spectra (FTIR), particle size determination, thermogravimetric analysis and so on. As well as, the O/W Pickering emulsions prepared with M-CNFs as a stabilizer has good performance in the diameter and particle size distribution, most droplet sizes can be maintained within 5 μm, and unimodal distribution was presented. It can show more stable performance under medium and alkaline conditions (pH = 7–11), and has certain anti-ion ability. Thus, this study has potential applications in coating, paint, sewage treatment and other fields. [ABSTRACT FROM AUTHOR]