Search Results (705)

Ethylene–vinyl acetate (EVA) copolymers are widely used in packaging, films, foams, and adhesives because of their softness and optical clarity; however, their relatively low mechanical strength limits broader applications. In this study, a scalable masterbatch strategy was developed to reinforce EVA by introducing TEMPO-oxidized cellulose nanofibers (T-CNFs), pre-encapsulated within an ethylene–vinyl alcohol (EVOH) matrix. EVOH acted as a compatibilizer, establishing robust hydrogen bonding with T-CNFs (evidenced by a 2.73-fold increase in the hydrogen bonding index) and thereby promoting their uniform dispersion and strong interfacial adhesion in the hydrophobic EVA phase. The resulting nanocomposites demonstrated significant improvements in mechanical performance, achieving a maximum 1.54-fold increase in tensile strength and a 1.42-fold increase in Young’s modulus compared to neat EVA. These findings highlight a practical route to produce bio-based, mechanically enhanced EVA nanocomposites with potential for industrial-scale applications. Full article

Fine and ultra-fine sugarcane bagasse (SCB) fractions (≤200 μm) that are naturally generated during industrial grinding have been systematically overlooked in lignocellulosic pretreatment research. Previous studies have largely relied on commercially processed pulps or coarse particles (>200 μm), typically without systematic size fractionation. Here, we demonstrate that these fine fractions—including ultra-fines (≤45 μm), which are often excluded from analytical workflows due to concern about excessive degradation—are viable feedstocks for producing lignin-containing cellulose nanofibers (LCNF) via a sequential thermal hydrolysis treatment (THT)–deep eutectic solvent (DES) pretreatment specifically designed to retain lignin. Size-fractionated SCB (≤45, 45–100, and 100–200 μm) was subjected to THT (190 °C, 15 min), followed by DES treatment using choline chloride/urea (1:2 molar ratio, 130 °C, 2 h). Multi-technique characterization using Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and X-ray diffraction (XRD) indicated substantial hemicellulose removal (>70%), effective lignin retention (7.6–9.1%), cellulose enrichment (74.0–77.5%), and preservation of cellulose I structure allomorph. The crystallinity index increased from 46.5–52.7% after THT to 56.7–57.2% after DES treatment, and notably, uniform compositional and structural features were obtained across all particle size classes after DES treatment. Subsequent high-pressure microfluidization (700 bar, five passes) yielded LCNF with consistent morphology across all fractions: uniform fibril diameters (24.6–26.2 nm), a discernible lignin coating, and excellent colloidal stability (zeta potential: −86.3 to −95.0 mV). Field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) confirmed well-dispersed nanofibrous networks. Collectively, these findings show that the full range of fine SCB fractions can be effectively valorized into high-performance LCNF through sequential THT–DES pretreatment, enabling comprehensive utilization of industrial grinding outputs and advancing circular bioeconomy objectives. Full article

Wood–polymer composites (WPCs) consistently garner considerable attention owing to their material versatility and sustainability, resulting in numerous review studies across diverse disciplines. Nonetheless, since a comprehensive synthesis that consolidates these disparate reviews is lacking, this study performs a meta-synthesis of review articles focused on WPCs employing a science-mapping approach enhanced by CiteSpace software. A systematic search of the Web of Science Core Collection (last updated in June 2025) was conducted, yielding 51 review-type articles selected using PRISMA screening guidelines. Network-based co-citation, clustering, and keyword analyses reveal that recent WPC research centers on three interconnected areas: (i) reinforcement and interfacial engineering, (ii) processing–structure–property relationships, and (iii) sustainability-focused design involving recycling, fire safety, thermal pretreatment, and PCM-based thermal management. Sixteen author/reference clusters and nine keyword clusters highlight well-defined knowledge communities on durability and fire safety, nano- and bio-based reinforcements, recycled and bioplastic matrices, and advanced manufacturing techniques such as co-extrusion, flat-pressing, 3D printing, and wood–polymer impregnation. Timeline and burst analyses show that mechanical performance remains the primary focus, while emerging areas include recycled/waste-derived polymers, cellulose micro- and nanofibers, moisture-resistant hybrids, and wood-based additive manufacturing for construction applications. Full article

At present, composite phase change materials are widely studied for battery thermal management. However, to ensure the battery’s thermal safety, it is necessary not only to control the temperature during regular operation, but also to prevent sudden thermal runaway. This basic function depends on the flame-retardant properties of the composite phase change materials. In this study, a hexagonal double-layer hollow nanocage S2 with defect orientation was prepared and combined with carbon nanotubes (PNT) derived from polypyrrole (PPy) tubes to form a high adsorption mixture. Multifunctional composite phase change material PNT/S2@PEG/TEP was prepared by adsorbing and coating polyethylene glycol 8000 (PEG-8000) and triethyl phosphate (TEP) with microfibrillated cellulose nanofibers (CNF) as the skeleton. The characterization shows that its thermal conductivity is 0.65 W/m·K and its phase transition enthalpy is 146.1 J/g, demonstrating its excellent thermal regulation. Microcalorimetric testing (MCC) confirmed its flame-retardant ability, attributed to the strong adsorption of PNT/S2 on PEG-8000 and TEP, the improvement in PNT’s thermal conductivity, and the contribution of CNF to flexibility. This composite phase change material, with excellent comprehensive properties, has broad application prospects in thermal safety for electronic equipment, significantly expanding its practical scope. Full article

Biocomposite films based on polylactic acid (PLA) reinforced with cellulose nanofibers (CNFs) extracted from Salicornia ramosissima by-products were developed and characterised using solvent casting (SC) and electrospinning (ES) techniques. The primary objective was to assess their suitability as sustainable food packaging materials that are compatible with high-pressure processing (HPP). The SC films exhibited a transparent, homogeneous morphology with superior ductility and water vapour barrier performance, whereas the ES films displayed a fibrous, porous structure with enhanced tensile strength and rigidity. The incorporation of CNFs significantly improved the mechanical properties, particularly the tensile strength and Young’s modulus, with optimal reinforcement achieved at a loading of 0.5%. Thermal and spectroscopic analyses confirmed the effective integration of CNF without compromising the thermal stability of PLA. Pouch-type packages from CNF-reinforced SC films withstood industrial HPP conditions without rupture or leakage, demonstrating their technical feasibility for food packaging applications. This study presents the first demonstration of Salicornia ramosissima by-product valorisation for CNF production and its application in HPP-compatible food packaging, addressing both circular economy goals and emerging food processing technologies. Full article

This study investigated the preparation of bacterial nanocellulose yarn, a high-strength and high-modulus cellulose-based textile material. Compared with the previously used wet spinning and electrospinning methods, the film-cutting, drawing and twisting treatment method in this paper retains the natural structure of BNC. This can greatly transfer the high performance of BNC nanofibers to BNC yarns, making the mechanical properties of the prepared yarn much higher than those of the BNC yarns prepared by the above two methods. It was produced through a film-cutting and twisting process utilizing bacterial nanocellulose as the primary component. The effects of drafting and twisting on the characteristics and properties of the yarn were systematically examined. Comparative analyses were conducted between the bacterial nanocellulose yarn and conventional cotton yarn of equivalent fineness and twist in terms of appearance, tensile properties, frictional behavior, and bending resistance. Optimal tensile mechanical properties of the bacterial nanocellulose yarn were achieved at 1% elongation and a twist number of 160 r/20 cm, resulting in a breaking strength of 751.56 MPa and an elongation at break of 11.56%, surpassing those of cotton yarn of similar specifications. The spinnability assessment revealed a smooth surface for the bacterial nanocellulose yarn, characterized by low friction coefficient, robust bending resistance with a bending modulus of 718.76 GPa. These findings offer valuable empirical data and theoretical insights to guide the subsequent textile processing and utilization of bacterial nanocellulose yarn. Full article

Pineapple waste is an underexplored source for producing nanocomposites, from which nanocellulose, namely cellulose nanocrystals (CNCs) or cellulose nanofibers (CNFs), can be produced. This review summarizes extraction methods from different pineapple residues (leaves, crown leaves, stem, peel, pulp, and pomace), covering top-down processes (hydrolysis, oxidation, carboxymethylation, and mechanical fibrillation) and bottom-up strategies (ionic liquids and deep eutectic solvents). The review examines the influence of the morphology and crystallinity of nanocellulose on the functional performance of the nanocomposites. Strategies for processing pineapple-derived nanocellulose composites are analyzed by technique (solution casting, film stacking, and melt blending/extrusion) and polymer matrices (starch, PVA, chitosan, PLA, PHBV, PBAT, proteins, and polysaccharides), including typical loading levels for most polymer-reinforced systems (0.5–5 wt.%), while higher levels (15–50 wt.%) are used in particular cases such as PVA, CMC, and cellulosic matrices. The impact on mechanical strength, barrier behavior, UV shielding, and optical properties is summarized, along with reports of self-reinforced and hybrid cellulose-derived matrices. A benchmarking section was prepared to show nanocellulose loading ranges, trends in properties, and processing-relevant information categorized by type of matrix. Finally, the review describes the potential roles of pineapple waste within a bioeconomy context and identifies some extraction by-products that could be incorporated into diverse value chains. Full article

This study presents a complete and zero-waste valorization strategy for barley straw through the synthesis of bio-polyols and the concurrent utilization of its cellulose fraction as lignin-containing cellulose nanofibers (LCNF) for the development of bio-based polyurethane (PU) foams. Two types of bio-polyols were prepared: one derived from lignin isolated via biomass fractionation, named lignin bio-polyol (LBP), and another obtained directly from unfractionated barley straw, called straw bio-polyol (SBP), thereby incorporating all lignocellulosic constituents into a single reactive matrix. LCNF, produced from the same feedstock, was incorporated at different loadings to achieve full biomass utilization and reinforce the polyurethane foam structure. Foams prepared with LBP exhibited lower density and a more homogeneous structure, whereas those synthesized with SBP developed a stiffer, more crosslinked network. The incorporation of LCNF generally increased apparent density and mechanical performance, with optimal reinforcement at 3 wt.% in foams with SBP and 5 wt.% in LBP foams, corresponding to a 62.5 and 121% enhancement in compressive strength relative to their respective control foams. Moreover, the use of barley straw bio-polyol shifted some thermal degradation peaks toward higher temperatures, evidencing improved thermal resistance. Overall, this dual-route strategy provides a sustainable and versatile methodology for the comprehensive valorization of lignocellulosic biomass, enabling a systematic understanding of the role of each structural component in polyurethane foam synthesis. The resulting materials offer a renewable, low-impact pathway toward high-performance polymeric materials. Full article

The growing scarcity of natural renewable resources has accelerated interest in producing nanomaterials from waste streams. Nanomaterials offer exceptional reinforcement capabilities for advanced composites, driving the need for sustainable and scalable production routes. While prior reviews have broadly examined nanomaterial synthesis from biomass or industrial residues, they often overlook textile waste as a strategic feedstock. This review uniquely focuses on the upcycling of textile waste—one of the most abundant yet underutilized waste streams—into high-value nanomaterials, thereby advancing circular economy principles. Unlike earlier studies that primarily discuss energy recovery or generic recycling, this work systematically explores mechanical, chemical, and thermal conversion routes tailored for textiles, leading to the production of cellulose nanofibers, cellulose nanocrystals, and carbon nanoparticles, which represent a significant class of biodegradable nanomaterials. Furthermore, a comprehensive analysis of the physicochemical properties of the nanomaterials and their emerging applications in water purification and environmental remediation is provided. An alternative pathway for nanomaterial synthesis from waste rather than renewable sources, providing information on the effective extraction of nanomaterials from mixed fiber compositions and dye residues present in textile waste, is also highlighted. By addressing current challenges and outlining future research directions, this review establishes a roadmap for sustainable textile waste valorization, marking a critical step toward eco-friendly nanomaterial production. Full article

As a fundamental component of sodium-ion batteries, separators are considered to isolate two electrodes and simultaneously allow for the transport of ions. Cellulose separators have attracted widespread interest for their remarkable properties. In this study, we prepared composite separators comprising cellulose nanofibers (CNFs) and halloysite nanotubes (HNTs) for sodium-ion batteries. When the content of the HNT was up to 60%, the tensile strength and elongation at break of the composite separator (denoted as C/H-60) were 24.39 MPa and 2.22%, respectively. Importantly, the C/H-60 separator demonstrated a high porosity (69.08%), improved ionic conductivity (1.142 mS/cm), decent thermal stability, and good electrolyte retention (91.3% electrolyte uptake). The assembled sodium-ion battery containing the composite separators had an excellent rate capacity and cycling property. The proposed composite separators are expected to be applied in high-performance sodium-ion batteries. Full article

This study presents a comprehensive investigation into the large-scale production of synthetic and hybrid (nanoparticle-loaded) nanofibers using needleless electrospinning. A diverse range of polymers, including polyamide 6 (PA6) and its other polymer combinations, recycled PA6, polyamide 11 (PA11), polyamide 12 (PA12), polyvinyl butyral (PVB), polycaprolactone (PCL), polyacrylonitrile (PAN), polyvinylidene fluoride (PVDF), polyurethane (PU), polyvinyl alcohol (PVA), and cellulose acetate (CA), were utilized to fabricate nanofibers with tailored properties such as polymer solution concentrations and various solvent systems. Furthermore, an extensive variety of nano- and micro-particles, including TiO₂, ZnO, MgO, CuO, Ag, graphene oxide, CeO₂, Er₂O₃, WO₃, MnO₂, and hyperbranched polymers, were incorporated into the polymeric systems to engineer multifunctional nanofibers with enhanced structural characteristics. The study examines the impact of polymer–nano/micro-particle interactions, fiber morphology, and the feasibility of large-scale production via needleless electrospinning. The resulting nanofibers exhibited diameters starting from 80 nm, depending on the polymer and processing conditions. The incorporation of TiO₂, CeO₂, WO₃, Ag, and ZnO nanoparticles into 15% PA6 solutions yielded well-dispersed hybrid nanofibers. By providing insights into polymer selection, nano- and micro-particle integration, and large-scale production techniques, this work establishes a versatile platform for scalable hybrid nanofiber fabrication, paving the way for innovative applications in nanotechnology and materials science. Full article

Food packaging serves a pivotal role in daily life, facilitating the efficient transportation of food and extending its shelf life. Petroleum-derived plastic packaging is extensively employed; however, its non-biodegradable nature poses significant environmental pollution and ecological degradation. Natural polymers (e.g., proteins such as gelatin and corn gluten protein; polysaccharides including pectin, chitosan, starch, cellulose, and alginate) and synthetic polymers (e.g., polyvinyl alcohol, polylactic acid, and polyhydroxyalkanoates) can be utilized to fabricate food packaging films, thereby achieving green and eco-friendly objectives. Nevertheless, the inferior mechanical strength and inadequate antibacterial activity of biopolymer-based packaging have restricted their practical applications. In recent years, nanomaterials (e.g., nanoparticles, nanotubes, nanofibers, and nanosheets) have been employed to enhance the performance of food packaging, emerging as a research hotspot. Notably, nanoparticles possess unique properties, including a high specific surface area, excellent dispersibility, and multifunctionality, which enables them to be easily incorporated into film matrices. Owing to their unique chemical structures, nanoparticles form strong interactions with film matrices, leading to a denser spatial structure. This not only markedly enhances the mechanical strength of the films, but also simultaneously improves their antibacterial and antioxidant capabilities. This review classifies and summarizes common nanomaterials based on their chemical compositions, providing a theoretical foundation and technical reference for the future development and application of nanomaterials in the field of bio-based active food packaging. Full article

In this work, nanofibers and cellulose nanocrystals from the native Amazonian bamboo Guadua weberbabeuri were used in structural cementitious composites. Through the preparation of bamboo nanofibers—bleached cellulose pulp (BCP) and cellulose nanocrystals (CNC), as well as obtaining shredded bamboo (SB) and delignified cellulose pulp (DCP)—the additions corresponding to the additive nanomaterials were characterized with physical tests such as water absorption, specific mass, void index, and dimensional variation. A mechanical tensile strength test was carried out at 28 days, with an incorporation content of 0.40% of mass in relation to the cement. The results indicated, in relation to the control, improvement in the physical properties, especially in the additions with nanofibers and cellulose nanocrystals. For the mechanical tensile strength tests, the indicator allowed an increase of 14.60% with the addition of nanofibers and 12.70% in the addition of nanocrystals. Therefore, with the execution carried out, it could be seen that the incorporation was able to generate optimization in the joint performance of the materials under analysis, reinforcing the practices and ideals arising from civil engineering, nanotechnology, and sustainability. Full article

High-performance spun bionanocomposite fibers, composed of high-molecular-weight chitosan (HMW), low-molecular-weight chitosan “oligomers” (LMW), and cellulose nanofibers (CNFs), were successfully fabricated via gel spinning of viscous aqueous chitosan (CHI) based formulations into a NaOH coagulation bath. The X-ray diffraction (XRD) analysis revealed that the incorporation of cellulose nanofibers contributed to enhance crystallinity of chitosan in spun fibers. The spinning process, which comprised sequential acidic solubilization, basic neutralization, stretching, and drying steps, produced chitosan/CNF composite fibers with high crystallinity, further enhanced by the incorporation of low molecular weight chitosan. The cellulose nanofibers seem to promote CHI crystallization, by acting as nucleation sites for the nucleation and growth of chitosan crystals, with those latter of LMW further enhancing crystallization and orientation due to higher mobility of shorter polymer chains. Two-dimensional XRD patterns demonstrated the preferential alignment of both CNFs and chitosan crystals along the fiber axis. Increasing the proportion of short-chain chitosan led to a reduction of the viscosity of collodion, facilitating the spinning of solutions with higher polymer concentrations. The X-ray diffraction (XRD) analysis revealed that the addition of low-molecular-weight chitosan (LMW), with an intermediate molecular weight Mw of ~4.4 × 10⁴ g/mol, produced the most significant improvements in the crystallinity index (CrI) and orientation. This structural enhancement corresponded to superior mechanical properties like Young’s modulus, yield stress σ_y, and stress-at-break σ_b of the processed composite fibers. By incorporating that intermediate molecular weight chitosan, a Young’s modulus as high as 20 GPa was achieved for the spun composite fibers, which was twice higher than the modulus of around 10 GPa obtained by adding the lowest molecular weight chitosan of Mw ~ 2.9 × 10⁴ g/mol in the composite, and largely above the modulus of around 5 GPa obtained for fiber just spun with chitosan without incorporation of cellulose nanofibers. Full article

Electrospun fibers serve as a medium for the targeted release of active compounds, facilitating the desired therapeutic effects in drug administration. The point of this study was to find the best conditions for making electrospun fibers from cellulose acetate (CA) and poly(ε-caprolactone) (PCL), mixed with pure oxyresveratrol extract from Artrocarpus lakoocha Roxberg (Moraceae). Additionally, the study focused on evaluating the antioxidant properties, antityrosinase activity, and freeze–thaw stability of the resulting fibers. We incorporated a concentration of oxyresveratrol at 0.1% w/w into various mass ratios of CA/PCL blended fiber sheets (1:0, 3:1, 1:1, 1:3), utilizing mixed solvents of acetone/DMF (2:1% v/v) and chloroform/DMF (9:1% v/v) for preparation. The fiber sheets displayed a continuous and uniform structure, with fiber diameters ranging from 300 to 1000 nanometers. We investigated the release kinetics of oxyresveratrol from the fibrous substrates using the total immersion technique, specifically in phosphate-buffered saline at a pH of 7.4. The results showed that the fiber sheet with a 3:1 w/w ratio of CA to PCL and a 0.1 w/w loading of oxyresveratrol showed the most significant release of oxyresveratrol at the 2 h mark, and it continued to release consistently at this peak value for up to 24 h. The antioxidant and anti-tyrosinase properties of oxyresveratrol in fiber sheets were more stable than those of free oxyresveratrol at the same concentrations. The fiber sheet presents a promising avenue for a user-friendly transdermal patch application. Full article