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Cellulose is a homopolymer composed of β-glucose units linked by 1,4-beta linkages in a linear arrangement, providing its structure with intermolecular H-bonding networking and crystallinity. The participation of hydroxy groups in the H-bonding network results in a low-to-average nucleophilicity of cellulose, which is insufficient for executing a nucleophilic reaction. Importantly, as a polyhydroxy biopolymer, cellulose has a high proportion of hydroxy groups in secondary and primary forms, providing it with limited aqueous solubility, highly dependent on its form, size, and other materialistic properties. Therefore, cellulose materials are generally known for their low reactivity and limited aqueous solubility and usually undergo aqueous medium-assisted pretreatment methods. The cationization of cellulose materials is one such example of pretreatment, which introduces a positive charge over its surface, improving its accessibility towards anionic group-containing molecules or application-targeted functionalization. The chemistry of cationization of cellulose has been widely explored, leading to the development of various building blocks for different material-based applications. Specifically, in coloration applications, cationized cellulose materials have been extensively studied, as the dyeing process benefits from the enhanced ionic interactions with anionic groups (such as sulfate, carboxylic groups, or phenolic groups), minimizing/eliminating the need for chemical auxiliaries. This study provides insights into the chemistry of cellulose cationization, which can benefit the material, polymer, textile, and color chemist. This paper deals with the chemistry information of cationization and how it enhances the reactivity of cellulose fibers towards its processing. [ABSTRACT FROM AUTHOR]

Paper-based packaging materials have gained attention from academia and industry for their outstanding environmental sustainability advantages. However, they still encounter major challenges, such as low mechanical strength and inadequate functionality, hindering the replacement of unsustainable packaging materials. Inspired by the remarkable strength of trees provided by cellulose fibers and the water and heat protection of trees provided by bark, this study developed a new biomass-based packaging material (SNC-C) that combines strength, thermal insulation, and water resistance. The material was created by simply blending straw nanocellulose (SNC) with oak bark (i.e., cork), which naturally provides water-resistant, thermal insulation, and unique regenerative properties. The dense layered structure formed entirely by SNC generates a tensile strength reaching up to 60.93 MPa. With the cork cavity structure, the heat transfer rate of the obtained material is reduced to 2.90–3.01 °C/(cm·min). The combining of the closed-cell structure and the suberin component of the cork results in a low water vapor transmission rate (WVTR) of the material of 400.30 g/(m2·24 h). This all-biomass material with excellent performance and low environmental footprint offers a promising solution for the development of sustainable multifunctional packaging materials. [ABSTRACT FROM AUTHOR]

Cigarette filter microplastics are composed of cellulose acetate that does not undergo biological or photo-degradation. These microplastics are readily dispersed and can be found abundantly in water, soil, and air. These fibers possess high absorption capabilities, allowing them to collect and retain pollutants such as toxic elements. As a result, they are regarded as potential dangers to living organisms. The purpose of this study was to analyze the immune response of human peripheral blood mononuclear cells (PBMCs) when exposed to cigarette filter microfibers, measuring the secretion of the inflammatory cytokines TNFα (tumor necrosis factor-alpha) and IL-6 (interleukin-6). In this study, we examined how used cigarette cellulose acetate microfibers affect the viability of peripheral blood mononuclear cells in an appropriate culture medium at three concentrations: 50, 100, and 200 µg/ml. In addition, this study investigated the release of inflammatory cytokines TNFα and IL6 from PBMCs exposed to 200 µg/ml cigarette filter cellulose acetate. The results showed that increasing the concentration of cellulose acetate fibers of one of the brands in the culture medium has a significant effect on reducing cell viability. The 200 µg/ml in DW is more effective than 50 and 100 µg/ml in reducing cell viability. Peripheral blood mononuclear cells showed an inflammatory immune response when exposed to 200 µg/ml cellulose acetate from cigarette filters. They produced inflammatory cytokines that showed a significant increase compared to the control sample. In general, it can be concluded that cellulose acetate fibers in contact with body cells stimulate them and cause an inflammatory response. [ABSTRACT FROM AUTHOR]

Cigarette butts are classified as plastic waste due to their composition of cellulose acetate fibers and are commonly found in beach sand. Their persistence in the environment, low biodegradability, and potential to interact with metals and metalloids during the aging process make them a significant subject of interest for research on coastal marine ecosystems. The aim of this study is to investigate the presence of metals such as hexavalent chromium Cr (VI), cadmium (Cd), and the metalloid arsenic (As) in cigarette butts (CBs), cigarette butt fibers (CBFs), and sand on a tourist beach in Cartagena, Colombia. The goal is to establish a baseline for potential contamination on the beach due to these elements. The methodology includes collecting samples of CBs, CBFs, and sand from different beach usage zones (active, rest, and service) and conducting standardized laboratory tests using atomic absorption spectroscopy for As and Cd and the standard colorimetric method for Cr (VI). The main findings indicate that arsenic levels reached 7.69, 5.75, and 3.47 mg As/kg in the sand, CBs, and CBFs, respectively. Cadmium and hexavalent chromium were found to be below the detection limit for the applied methodology. Additionally, mercury was detected at a concentration of 0.37 mg Hg/L in CBFs in the active zone in October. [ABSTRACT FROM AUTHOR]

There is growing interest in the use of bio-based materials as viable alternatives to petrochemical-based packaging. However, the practical application of bio-based films is often hampered by their poor barrier and poor mechanical properties. In this context, cellulose nanofibers (CNFs) have attracted considerable attention owing to their exceptional biodegradability, high aspect ratio, and large surface area. The extraction of CNFs from agricultural waste or non-food biomass represents a sustainable approach that can effectively balance cost and environmental impacts. The functionalization of CNFs improves the economics of raw materials and production processes while expanding their applications. This paper reviews recent advances in cellulose nanofibers, including their sources, surface modification, and characterization techniques. Furthermore, we systematically discuss the interactions of CNFs with different composites in the development of functional food films. Finally, we highlight the application of cellulose nanofiber films in food preservation. Due to their environmentally friendly properties, CNFs are a promising alternative to petroleum-based plastics. The aim of this paper is to present the latest discoveries and advances in CNFs while exploring the future prospects for edible food films, thereby encouraging further research and application of CNFs in the field of active food packaging. [ABSTRACT FROM AUTHOR]

Bamboo is widely distributed around the world as an excellent renewable resource. However, the structural and morphological changes in the bamboo samples in extracting bamboo cellulose fiber using alkaline-acidic sodium chlorite are unclear, and the potential for preparation of cellulose packaging films is yet to be explored. In this paper, the changes in micro-morphology, chemical structure, and pyrolytic behavior of moso bamboo powder during alkaline and acidic sodium chlorite pretreatment were intensively investigated. The bamboo cellulose fiber (BC) diameter decreased from 14.41 to 11.79 µm with the treatment as a result of the removal of amorphous materials such as lignin and hemicellulose. The BC was dissolved in NaOH/urea aqueous solution, and all-cellulose composite films were obtained with excellent mechanical properties and high transparency. When the BC contents reached 4 wt%, the resulting films had a light transmittance of about 90% in the visible light range (400–780 nm), and the tensile strength was as high as 57.9 MPa, which was much higher than that of the polyethylene packaging film (PE, 35 MPa). In addition, the film also suggests superior biodegradability compared to PE films. Therefore, the current shortage of raw materials and environmental pollution faced by plastic packaging materials may be expected to gain new inspiration in this study. [ABSTRACT FROM AUTHOR]

The agriculture and agri-food sectors produce substantial amounts of plant-based waste. This waste presents an identifiable research opportunity to develop methods for effectively eliminating and managing it in order to promote zero-waste and circular economies. Plant-based waste and by-products are acknowledged as valuable sources of bioactive compounds, including cellulose fibers. Direct application of these fibers in non-food sectors such as textiles can reduce the environmental impact of secondary raw materials. This review aims to provide an overview of novel concepts and modern technologies for efficiently utilizing plant-based waste and by-products from the agricultural and agro-industrial sectors to extract fibers for a variety of final applications, including the fashion industry. Two major routes are identified to produce cellulose fibers: the extraction and purification of natural cellulose fibers and the extraction and purification of cellulose pulp that is further processed into manmade cellulosic fibers. Scalability of experimental results at the laboratory or pilot level is a major barrier, so it is critical to develop closed-loop processes, apply standardization protocols, and conduct life cycle assessments and techno-economic analyses to facilitate large-scale implementation. [ABSTRACT FROM AUTHOR]

Cellulose-based materials are now commonly used, including in the field of acoustic comfort. Often presented as a less environmentally impactful alternative to traditional acoustic absorbents (such as melamine, glass wool, etc.), these cellulose-based materials are more frequently derived from recycling, undergoing, in most cases, a technical process that allows these cellulose fibers to be obtained, thus inheriting the acoustic properties of the latter, with limited or even non-existent control. This paper proposes a manufacturing process that allows for the production of cellulose foam with precise control over its porosity, pore size, and interconnections. In addition to exhibiting good sound absorption properties, this process also enables the fabrication of gradient-porous structures and other hybrid materials, which can result in remarkable sound absorption properties. [ABSTRACT FROM AUTHOR]

Recently, numerous studies have been carried out with natural fibers in cementitious composites, due to the viability of using this type of fiber as a substitute for synthetic fibers. In this field of study, the present research aims to evaluate the feasibility of using corn straw fiber for the production of innovative cementitious composites. Mortars with a composition of 1:1:6:1.55 (cement/lime/sand/water) containing 0, 2.5 and 5% corn straw fiber were produced. The corn straw fibers were treated with three different alkaline products: sodium hydroxide (NaOH), potassium hydroxide (KOH) and calcium hydroxide (Ca(OH)2). The compositions were evaluated by means of compressive strength, water absorption, density and porosity and consistency tests. Characterization tests were also carried out on the natural fibers subjected to the different treatments, where it was observed that chemical characterization revealed an increase in crystalline cellulose from 59.03% to 63.50% (NaOH), 62.41% (KOH) and 60.40% (Ca(OH)2), which enhances fiber strength. In the mortars, it was observed that the water absorption results were reduced when the alkaline treatments were used, reducing from 15.95% (composition without fibers) to 6.34% and 6.61% in the compositions with 2.5% and 5.0% of fibers treated with KOH, for example. The effects were also positive in the compositions with fibers treated in NaOH, where the water absorption values were 7.59% and 7.88% for the compositions containing 2.5% and 5.0% of treated fiber, respectively. Alkaline treatments also promote an increase in compressive strength when comparing the results of mortars with natural fibers and fibers treated with NaOH, for example. The result for mortars containing 5.0% untreated fibers was 0.22 MPa, while for the composition containing 5.0% fibers treated with NaOH, it was 3.79 MPa, an increase of more than 15x. This behavior is justified by the effect of the treatment, which, in addition to removing impurities from natural fibers, such as sugar, increases the crystalline cellulose content and the adhesion between fiber and matrix. Based on the results obtained, it is possible to conclude that (i) the treatment with NaOH increases the crystallinity and tensile strength of the fibers, promoting good properties for innovative cementitious composites; (ii) the treatment with KOH degrades the cellulose structure of the fiber, reducing the crystallinity and tensile strength; this promotes greater adhesion of the fiber to the matrix, reducing porosity and water absorption, but promotes a reduction in compressive strength when compared to composites with 2.5% natural fiber; and (iii) the treatment with Ca(OH)2 presents a reduction in water absorption and porosity, due to the impregnation of calcium in the fiber that improves the adhesion between fiber and matrix. [ABSTRACT FROM AUTHOR]

Natural fiber composites have gained increasing attention due to sustainability considerations. One often neglected aspect is the potential for the mechanical recycling of such materials. In this work, we compounded injection-molded polypropylene (PP) and polylactic acid (PLA) short cellulose fiber composites with fiber shares up to 40 percent by weight. Both matrix materials were reinforced by the addition of the fibers. We investigated a trifold full recycling process, where we subjected the materials produced in the first place to compounding, injection molding, testing, and shredding, and then repeated the process. Although the materials' properties assigned to degradation were found to decrease with progressive recycling, attractive mechanical properties could be preserved even after the third reprocessing cycle. [ABSTRACT FROM AUTHOR]

Packaging is an integral part of every food product, especially cheese. An important goal is to protect the product from spoiling and drying out. Two types of cheese were tested: soft goat's cheese and hard goat's cheese. They were evaluated for gloss, water activity, and colour. The aim of the research was to assess changes in the water activity of goat cheese in correlation with changes in gloss and color during storage in various forms of packaging, depending on consumer habits. The research problem was based on consumer observations regarding the repackaging of dairy products, including goat's cheese. Consumers have reported such a problem in previous studies. The question was asked: will it be necessary in the future to indicate to the consumer the appropriate form of repackaging for a given goat's cheese? It was shown that the best packaging for storing open feta-type goat salad cheeses was aluminum foil and hard goat cheeses in the producer's packaging. The method of storage only affects the change in gloss in the case of goat salad cheese and parameter a* hard cheese. At the same time, the need was noted to develop appropriate packaging that would serve to protect the product from spoilage and would not pose a threat to the natural environment after being thrown into the trash. Wrapping soft goat cheeses in cellulose fiber paper reduced water activity by 5% after 14 days of storage but did not encourage re-consumption. The key task for future research is, therefore, to carry out regular consumer surveys. Therefore, it is necessary to choose (develop) a packaging that would preserve the original quality of the cheeses when stored in these conditions. [ABSTRACT FROM AUTHOR]

In the papermaking industry, cellulose fibers often undergo a bleaching process which affects the surface of the fibers, or their overall morphology. The surface of the produced paper, which is most often used as a printing substrate, depends on the production method, the arrangement of the cellulose fibers, and the quantity and fineness of the filler. The micro-irregularities caused by the uneven distribution of fibers and surface particles of the filler make the paper's surface rough and affect the print quality and its stability when exposed to light from the moment of production to use. The unbleached cellulose fibers in the printing substrate contain natural pigments, lignin and hemicellulose that absorb UV radiation, as opposed to bleached fibers, which have higher whiteness and lightfastness. Therefore, the influence of UV radiation on the surface roughness of prints made on papers with natural unbleached and bleached hemp fibers was analyzed. This research confirmed that papers formed from unbleached fibers have rougher surface and that printed graphic products from bleached fibers have higher stability to UV radiation than those from natural, unbleached hemp fibers after 96 h of treatment in the Suntest chamber. [ABSTRACT FROM AUTHOR]

Copyright of Environmental & Social Management Journal / Revista de Gestão Social e Ambiental is the property of Environmental & Social Management Journal 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.)

Cellulose is widely distributed in higher plants and constitutes the most abundant natural biopolymer on Earth. Nanocellulose is a cellulose material with nanoscale dimensions, obtained through special processing and treatment. Up to now, nanocellulose has been widely investigated as a biosorbent to absorb various types of pollutants in wastewater due to its excellent properties, such as large specific surface area, antifouling behaviour, high aspect ratio, high heat resistance, excellent mechanical properties, biodegradability and biocompatibility. In addition, nanocellulose can be rationally structured by different recombination techniques such as membranes, sponges, aerogels, hydrogels and microspheres and provide specialised functionality for the adsorption of various types of pollutants from wastewater. This review introduces the basic properties, classification and modification methods of nanocellulose; discusses the preparation strategies of nanocellulose-based recombinant materials (including vacuum/pressurised filtration, sol–gel and electrospinning); reviews research progress in the adsorption of organic dyes and heavy metal Cr, as well as the separation of oil/water using nanocellulose-based recombinant materials; and explores the potential of nanocellulose in treating tannery wastewater. Finally, the problems faced by nanocellulose-based recombinant materials and future prospects are presented. [ABSTRACT FROM AUTHOR]

The depletion of conventional materials and their adverse environmental impacts have prompted a shift toward sustainable alternatives in composite materials engineering. In pursuit of this objective, this study investigated the mechanical properties of polypropylene matrix composites reinforced with Cordenka, an artificial cellulose fiber, and compared them to those reinforced with ramie, a natural cellulose fiber. Continuous strand composites were developed using the Multi-Pin-assisted Resin Infiltration (M-PaRI) process. The strands were subsequently sectioned into 15 mm lengths and injection-molded into dumbbell and strip specimens for mechanical characterization. The results showed that 20 wt% Cordenka/PP composites exhibited a tensile strength of 68.7 MPa, 2.04 times higher than neat PP and 1.66 times greater than the 20 wt% ramie/PP composites. Impact testing further demonstrated that Cordenka/PP composites absorbed 2 to 2.5 times more impact energy than ramie/PP composites, regardless of the presence of notches. Fiber length analysis indicated that Cordenka fibers maintained their length beyond the critical fiber length, allowing for efficient stress transfer and acting as a more effective reinforcement compared to ramie fibers, which were below this threshold. Consequently, the Cordenka/PP composites exhibited significantly enhanced mechanical performance. Scanning electron microscopy (SEM) analysis revealed fewer fiber pullouts in ramie-reinforced composites, suggesting superior interfacial adhesion to the PP matrix, although it did not translate to higher mechanical properties. These findings underscore the potential of Cordenka as a sustainable alternative to synthetic, non-biodegradable fibers in PP composites, providing improved mechanical properties and promising prospects for advanced composite applications. [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.)

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.)

New asphalt mixtures have been improved by using fibers (polypropylene, polyester, asbestos, carbon, glass, nylon, lignin, coconut, sisal, recycled rubber, PET, wood, bamboo, and cellulose), reducing the temperature and compaction energy for their collocation, minimizing the impact on the environment, increasing the tenacity and resistance to cracking of hot mix asphalt (HMA), preventing asphalt drainage in a Stone Mastic Asphalt (SMA). Hence, this paper aims to evaluate the influence of the chemical (lignin content, ash, viscosity, degree of polymerization, and elemental analysis), morphological (SEM), spectroscopic (FTIR-ATR and XRD), and calorimetric (ATG and DSC) properties of celluloses from bagasse Agave tequilana Weber var. Azul (ABP), corrugated paperboard (CPB) and commercial cellulose fiber (CC) as Schellenberg drainage (D) inhibitors of the SMA. The ABP was obtained through a chemical process by alkaline cooking, while CPB by a mechanical refining process. The chemical, morphological, spectroscopic, and calorimetric properties were similar among the analyzed celluloses, but CPB and ABP cellulose are excellent alternatives to CC cellulose for inhibiting drainage. However, CPB is the most effective at low concentrations. This is attributed to its morphology, which includes roughness, waviness, filament length, orientation, and diameter, as well as its lignin content and crystallinity. [ABSTRACT FROM AUTHOR]

Recent studies have focused on the development of bio-based products from sustainable resources using green extraction approaches, especially nanocellulose, an emerging nanoparticle with impressive properties and multiple applications. Despite the various sources of cellulose nanofibers, the search for alternative resources that replace wood, such as Lygeum spartum, a fast-growing Mediterranean plant, is crucial. It has not been previously investigated as a potential source of nanocellulose. This study investigates the extraction of novel cellulose micro/nanofibers from Lygeum spartum using a two-step method, including both alkali and mechanical treatment as post-treatment with ultrasound, as well as homogenization using water and dilute alkali solution as a solvent. To determine the structural properties of CNFs, a series of characterization techniques was applied. A significant correlation was observed between the Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) results. The FTIR results revealed the elimination of amorphous regions and an increase in the energy of the H-bonding modes, while the XRD results showed that the crystal structure of micro/nanofibers was preserved during the process. In addition, they indicated an increase in the crystallinity index obtained with both methods (deconvolution and Segal). Thermal analysis based on thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) confirmed improvement in the thermal properties of the isolated micro/nanofibers. The temperatures of maximum degradation were 335 °C and 347 °C. Morphological analysis using a scanning electron microscope (SEM) and atomic force microscope (AFM) showed the formation of fibers along the axis, with rough and porous surfaces. The findings indicate the potential of Lygeum spartum as a source for producing high-quality micro/nanofibers. A future direction of study is to use the cellulose micro/nanofibers as additives in recycled paper and to evaluate the mechanical properties of the paper sheets, as well as investigate their use in smart paper. [ABSTRACT FROM AUTHOR]

In this paper, we present the synthesis of composite materials comprised of α-cellulose and sugarcane bagasse cellulose fibers grafted with lactic acid and ε-caprolactone. These fibers were incorporated as reinforcements into a PLA matrix by extrusion, producing composite materials with improved mechanical properties. The grafting of lactic acid and ε-caprolactone onto the fibers was confirmed by FTIR spectroscopy, demonstrating the chemical modification of the fibers. The morphology of the fibers and composites was analyzed through scanning electron microscopy (SEM), showing that the fibers are encapsulated within the polymeric matrix. This suggests good PLA–fiber interaction for the 90 PLA/10 α-Cel, 90 PLA/10 LAC-g-α-Cel, and 90 PLA/10 ε-CL-g-α-Cel composite materials. The obtained composite materials were tested under tensile loading. Incorporating 10 wt% of LAC-g-FBA-Cel and α-Cel-g-FBA-Cel grafted fibers into the PLA matrix improved the tensile modulus by 28% and 12%, respectively, compared with PLA. The maximum tensile strength values obtained were for composite materials with 10 wt% PLA/α-Cel, LAC-g-α-Cel, and FBA-Cel with 23, 27, and 37% concerning PLA. DSC thermal studies showed a reduction in the glass transition temperature in the composites with grafted fibers. The results suggest better interfacial adhesion between the PLA matrix and both grafted and non-grafted α-cellulose fibers, which contributes to the observed improvements in the mechanical and thermal properties of the composite materials. The results demonstrate that the composites can be produced through extrusion. Once the optimal concentration has been determined, α-cellulose or sugarcane bagasse grafted with lactic acid and ε-caprolactone can be incorporated into the PLA matrix, exhibiting adjustable properties. [ABSTRACT FROM AUTHOR]

Polymeric fibers are often used as a drying additive for refractory castables because they can increase their permeability, reducing the risk of pressurization that is believed to trigger explosive spalling. Despite the potential of synthetic polymers to be engineered and obtain desired properties, the required parameters for inducing permeability enhancement remain unclear. This inhibits the development of novel designed drying additives and improvement of the numerical models. This work investigates the effect of polypropylene (PP), polyethylene (PE) and cellulose fibers on the water transport in refractory castables through rapid neutron tomography, enabling the in situ visualization of the water distribution, the drying front advance and the size, intensity and duration of moisture accumulation. PE and cellulose fibers accelerate drying fronts earlier than PP, in which PE exhibits larger moisture accumulation, residual moisture behind its drying front and a slower drying rate at higher temperatures despite the early water removal initiation. In contrast, cellulose emerged as a better candidate, due to a swelling–shrinkage based mechanism. The neutron tomography observations unveil the dynamic and intricate effect of fibers in the permeability, emphasizing that safer industrial processes require a deeper understanding of the underlying mechanisms to develop better fibers and accurate numerical models. [ABSTRACT FROM AUTHOR]

This study sequentially extracted five cell wall polysaccharides from passion fruit peels using water, cyclohexane-trans-1,2-diamine tetra-acetate (CDTA), Na2CO3, and NaOH at varying concentrations. The composition, structure, and physical properties of these polysaccharides were investigated. The results demonstrated that water-extracted polysaccharides yielded the highest content, accounting for 9.04% of the dry weight of the peel's alcohol-insoluble residue. This was followed by polysaccharides extracted with 4 mol/L NaOH (8.15%), 0.05 mol/L CDTA (7.38%), 0.05 mol/L Na2CO3 (5.36%), and 1 mol/L NaOH (3.89%). Water-extracted and 0.05 mol/L CDTA-extracted polysaccharides were dominated by homogalacturonan, with molecular weights of 198.46 kDa and 73.67 kDa, respectively. The 0.05 mol/L Na2CO3-extracted polysaccharides had a high percentage of rhamnogalacturonan (53.47%) and the most negligible molecular weight (30.29 kDa). The polysaccharides extracted with 1 mol/L NaOH and 4 mol/L NaOH were hemicellulosic in nature, primarily composed of xylose, glucose, mannose, and galactose. All polysaccharides exhibited shear-thinning flow behaviors in aqueous solutions. The 0.05 mol/L Na2CO3-extracted polysaccharides showed the highest apparent viscosity and demonstrated elastic behavior, with the elastic modulus G' exceeding the viscous modulus G". The water-extracted polysaccharides and the 0.05 mol/L CDTA-extracted polysaccharides exhibited a gel-to-sol transition at angular frequencies near 1.10 and 0.43 rad/s, respectively. The 0.05 mol/L Na2CO3-extracted polysaccharides displayed relatively excellent emulsifying ability and emulsion stability. Hemicellulosic polysaccharides exhibited lower viscosity and higher thermal stability. Thus, passion fruit peels contained abundant cell wall polysaccharides, with different polysaccharides showing varied potential for emulsification and food texture improvement. This study provides valuable insights for the in- depth development of the extraction and use of peel polysaccharide fractions. [ABSTRACT FROM AUTHOR]

In this study, a systematic review of the scientific literature was carried out to summarize the emerging evidence on microplastic pollution in natural caves. After the screening of 655 papers on the topic from a combined search on the Web of Knowledge and the Scopus databases, we found only 14 studies reporting quantitative data on microplastics from a total of 27 natural caves. Most of the assessments focused on water and sediment, with very limited investigations concerning the cave biota. Overall, the most common types of particles found in caves were small (<1 mm) fibers (~70–90% of items), transparent or light-colored, mostly made of polyethylene and polyethylene terephthalate. Anthropogenic cellulosic materials, however, represented a non-negligible portion of particles (i.e., ~20–30%). Microplastic concentrations in caves varied between 0.017 and 911 items/L for water and 7.9 and 4777 items/kg for sediment, thus falling within the levels of microplastic pollution found in other terrestrial, freshwater, and marine environments. Levels of microplastic pollution appear largely variable among caves, stressing the need to extend the geographic and environmental ranges of the assessments, which are currently concentrated on Italian caves on land, with very few case studies from other regions of the world and from marine caves. Despite their putative isolation, natural caves have a high vulnerability to microplastic contamination, requiring much more research effort to understand the potential risk that plastics pose to these fragile ecosystems. [ABSTRACT FROM AUTHOR]

Regenerated cellulose fibers are a highly adaptable biomaterial with numerous medical applications owing to their inherent biocompatibility, biodegradability, and robust mechanical properties. In the domain of wound care, regenerated cellulose fibers facilitate a moist environment conducive to healing, minimize infection risk, and adapt to wound topographies, making it ideal for different types of dressings. In tissue engineering, cellulose scaffolds provide a matrix for cell attachment and proliferation, supporting the development of artificial skin, cartilage, and other tissues. Furthermore, regenerated cellulose fibers, used as absorbable sutures, degrade within the body, eliminating the need for removal and proving advantageous for internal suturing. The medical textile industry relies heavily on regenerated cellulose fibers because of their unique properties that make them suitable for various applications, including wound care, surgical garments, and diagnostic materials. Regenerated cellulose fibers are produced by dissolving cellulose from natural sources and reconstituting it into fiber form, which can be customized for specific medical uses. This paper will explore the various types, properties, and applications of regenerated cellulose fibers in medical contexts, alongside an examination of its manufacturing processes and technologies, as well as associated challenges. [ABSTRACT FROM AUTHOR]

As the global population continues growing, the demand for textiles also increases, putting pressure on cotton manufacturers to produce more natural fiber from this already undersupplied resource. Synthetic fibers such as polyester (PET) can be manufactured quickly and cheaply, but these petroleum-based products are detrimental to the environment. With increased efforts to encourage transparency and create a more circular textile economy, other natural alternatives must be considered. This article discusses the existing condition and future possibilities for manmade cellulosic fibers (MMCFs), with an emphasis on using non-woody alternative feedstocks as a starting material. This work focuses on conversion technology suitable for producing textilegrade fibers from non-wood-based dissolving pulp, which may be different in nature from its woody counterpart and therefore behave differently in spinning processes. Derivatization and dissolution methods are detailed, along with spinning techniques and parameters for these processes. Existing research related to the spinning of non-woody-based dissolving pulp is covered, along with suggestions for the most promising feedstock and technology combinations. In addition, an emerging method of conversion, in which textile fibers are spun from a hydrogel made of an undissolved nano/micro-fibrillated fiber suspension, is briefly discussed due to its unique potential. Methods and concepts compiled in this review relate to utilizing alternative feedstocks for future fibers while providing a better understanding of conventional and emerging fiber spinning processes for these fibers. [ABSTRACT FROM AUTHOR]

The presence of harmful oxidizing gases accelerates the oxidation of cellulose fibers in paper, resulting in reduced strength and fading ink. Therefore, the development of highly sensitive NO2 gas sensors for monitoring and protecting books holds significant practical value. In this manuscript, ZnO/MoS2 composites were synthesized using sodium molybdate and thiourea as raw materials through a hydrothermal method. The morphology and microstructure were characterized by X-ray diffraction analysis (XRD), energy dispersive spectroscopy (EDS), field emission scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The ZnO/MoS2 composite exhibited a flower-like structure, with ZnO nanoparticles uniformly attached to the surface of MoS2, demonstrating advantages such as high specific surface area and good uniformity. The gas sensitivity of the ZnO/MoS2 nanocomposites reached its peak at 260 °C, with a sensitivity value around 3.5, which represents an improvement compared to pure ZnO, while also enhancing sensitivity. The resistance of the ZnO/MoS2 gas sensor remained relatively stable in air, exhibiting short response times during transitions between air and NO2 environments while consistently returning to a stable state. In addition to increasing adsorption capacity and improving light utilization efficiency, the formation of hetero-junctions at the ZnO-MoS2 interface creates an internal electric field that effectively promotes the rapid separation of photo-generated charge carriers within ZnO, thereby extending carrier lifetime. [ABSTRACT FROM AUTHOR]

Natural fiber composites have gained increasing attention due to sustainability considerations. One often neglected aspect is the potential for the mechanical recycling of such materials. In this work, we compounded injection-molded polypropylene (PP) and polylactic acid (PLA) short cellulose fiber composites with fiber shares up to 40 percent by weight. Both matrix materials were reinforced by the addition of the fibers. We investigated a trifold full recycling process, where we subjected the materials produced in the first place to compounding, injection molding, testing, and shredding, and then repeated the process. Although the materials’ properties assigned to degradation were found to decrease with progressive recycling, attractive mechanical properties could be preserved even after the third reprocessing cycle.

Abstract Research on polymer matrix composites has become increasingly important in both the academic and industrial sectors. The study of polymer-natural fiber composites, known for their eco-friendly properties, has gained significance. Sugarcane bagasse fibers, abundant as discarded agricultural byproducts, offer improved properties such as density, rigidity, strength, and cost-effectiveness, enhancing sustainability. As a result, experiments were performed on cellulose fibers pre-treated from sugarcane bagasse using 5% NaOH solution by simply soaking them for 4–5 h followed by washing with water. Further modifications involved esterification using phthalic anhydride and phthaloyl chloride via steam baths at 90 °C and oxidation using sodium percarbonate with a phase transfer catalyst (Adogen) at 80 °C. These chemically altered cellulose fibers exhibited significant peak changes in the FTIR spectra, a reduced crystallinity index in the XRD pattern, increased thermal stability as evidenced by TGA curve, and improved surface roughness in the SEM analysis. This paper emphasizes successful pretreatment procedures for isolating cellulose fibers from sugarcane bagasse and introduces three chemical treatments for surface functionalization which might find applications in the preparation of biocomposites.

Abstract Natural polymers are attractive sustainable materials for production of fibers and composite materials. Cotton and flux are traditional plants used to produce textiles with comforting properties while technologies like Viscose, Lyocell and Ioncell-F allowed to extent fiber use into regenerated cellulose from wood. Neither natural nor man-made fibers completely satisfy the needs for cellulose based fabrics boosting development of new approaches to bring more sustainability into the fashion. Technologies like Spinnova are arising based on the spinning of mechanically pretreated cellulose materials with a lower environmental impact though challenged by the fiber quality and strength related to the inconsistency of the mechanical fibers. Nanoscaled cellulose is an excellent solution to improve the consistency of spin fibers, but charges introduced by traditional chemical treatments prevent rebuilding native hydrogen bonding and compromise the mechanical properties especially in wet conditions. We used nanocellulose with low surface charge isolated using reactive eutectic media to spin fibers able to restore the native hydrogen bonding and enable constitutional mechanical strength of cellulose. We performed un-optimized spinning to reveal the intrinsic properties of the fibers and confirmed the preserved strength of wet fibers compliant with the low surface charge enabling further engineering towards cotton-like fabric from wood.

Of the three types of waste generated in beer processing, brewer's spent grain (BSG) is the most abundant and has a high potential for valorization. In this work, defatted BSG (DB) was subjected to an extraction process with subcritical water at different temperatures to obtain extracts rich in phenols and the cellulosic fractions, which were also purified by using hydrogen peroxide (H2O2). The results showed that the dry extracts obtained at 170 °C were richer in phenolics (24 mg Gallic Acid Equivalent (GAE) g−1 DB), but with lower antioxidant capacity (71 mg DB·mg−1 2,2-diphenyl-1-pikryl-hydrazyl). This extract also showed the highest antibacterial potential against L. innocua (80 mg·mL−1) and E. coli (140 mg·mL−1) than those obtained at lower temperatures. The purification of cellulose from the treated residues, using hydrogen peroxide, revealed that DB is a limited source of cellulose material since the bleached fractions showed low yields (20–25%) and low cellulose purity (42–71%), even after four bleaching cycles (1 h) at pH 12 and 8% H2O2. Despite this, the subcritical water extraction method highlights the potential of a simple process as a technological option to convert underutilized side streams like beer bagasse into added-value, potential ingredients for innovative food and pharmaceutical applications. [ABSTRACT FROM AUTHOR]

Both annual (cotton, flax, hemp, etc.) and perennial (trees and grasses) plants can serve as a source of cellulose for fiber production. In recent years, the perennial herbaceous plant miscanthus has attracted particular interest as a popular industrial plant with enormous potential. This industrial crop, which contains up to 57% cellulose, serves as a raw material in the chemical and biotechnology sectors. This study proposes for the first time the utilization of miscanthus, namely Miscanthus Giganteus "KAMIS", to generate spinning solutions in N-methylmorpholine-N-oxide. Miscanthus cellulose's properties were identified using standard methods for determining the constituent composition, including also IR and atomic emission spectroscopy. The dry-jet wet method was used to make fibers from cellulose solutions with an appropriate viscosity/elasticity ratio. The structural characteristics of the fibers were studied using IR and scanning electron microscopy, as well as via X-ray structural analysis. The mechanical and thermal properties of the novel type of hydrated cellulose fibers demonstrated the possibility of producing high-quality fibers from miscanthus. [ABSTRACT FROM AUTHOR]

Research on polymer matrix composites has become increasingly important in both the academic and industrial sectors. The study of polymer-natural fiber composites, known for their eco-friendly properties, has gained significance. Sugarcane bagasse fibers, abundant as discarded agricultural byproducts, offer improved properties such as density, rigidity, strength, and cost-effectiveness, enhancing sustainability. As a result, experiments were performed on cellulose fibers pre-treated from sugarcane bagasse using 5% NaOH solution by simply soaking them for 4–5 h followed by washing with water. Further modifications involved esterification using phthalic anhydride and phthaloyl chloride via steam baths at 90 °C and oxidation using sodium percarbonate with a phase transfer catalyst (Adogen) at 80 °C. These chemically altered cellulose fibers exhibited significant peak changes in the FTIR spectra, a reduced crystallinity index in the XRD pattern, increased thermal stability as evidenced by TGA curve, and improved surface roughness in the SEM analysis. This paper emphasizes successful pretreatment procedures for isolating cellulose fibers from sugarcane bagasse and introduces three chemical treatments for surface functionalization which might find applications in the preparation of biocomposites. [ABSTRACT FROM AUTHOR]

This study estimated genetic and phenotypic parameters, heritabilities, correlations, selection accuracy, and expected gain from selection for dry matter yield and nutritional traits in 178 half-sib ruzigrass families. Eight traits were evaluated, with nutritional quality measured via NIRS. Data analysis using mixed models and clustering revealed significant differences between progenies. Narrow-sense heritability ranged from 0.26 to 0.42, and selection accuracy ranged from 0.51 to 0.65. Genetic variation was lower for nutritional quality traits compared to dry matter yield. Dry matter yield had positive genetic correlations with neutral and acid detergent fiber and cellulose, but negative correlations with crude protein and hemicellulose. Clustering identified two groups of families: one correlated with in vitro dry matter digestibility and crude protein, and the other with remaining traits. Selecting for dry matter yield may reduce crude protein content but not affect digestibility; selecting for low fiber or high crude protein may improve forage quality. [ABSTRACT FROM AUTHOR]

Composite materials are synthesized by using natural cellulose fibers with matrix, due to their improved properties. In this work, banana and palm fibers are treated with 2% and 8% NaoH, respectively, for the removal of lignin and hemicelluloses. The hybrid composite was fabricated by using epoxy resin as the matrix and both the fibers as reinforcement through the hand lay-up method. By varying the banana and palm fibers in the range of 5-15% wt. and 7.5-22.5% wt. in the composite of 20% wt. and 30% wt. reinforcement, respectively, The composite consists of 5/15% wt. treated fibers, having more influence on compressive strength of 222.46 MPa and flexural strength of 535 MPa. However, 7.5/22.5% wt. treated composite has a higher impact resistance of 14.6 J and 10/10% treated composite gained a higher water absorption percentage weight of 1.16% at 216 hours. From the experiment, the composite with 5/15% wt. fibers of 20% wt. reinforcement and 80% wt. epoxy is suitable for making kitchen slabs. [ABSTRACT FROM AUTHOR]

This paper investigates the effects of pre-gelation on cellulose dissolved in LiCl/DMAc solutions to enhance the properties of regenerated cellulose materials. This study focuses on characterizing the crystallinity, molecular orientation, and mechanical performance of cellulose fibers and hydrogels prepared with and without pre-gelation treatment. X-ray diffraction (XRD) analysis reveals that crystallinity improvement from 55% in untreated fibers to 59% in fibers pre-gelled for 3 and 7 days, indicating a more ordered arrangement of cellulose chains post-regeneration. Additionally, XRD patterns show improved chain alignment in pre-gelled fibers, as indicated by reduced full width at half the maximum of Azimuthal scans. Mechanical testing demonstrates a 30% increase in tensile strength and a doubling of the compression modulus for pre-gelled fibers compared to untreated fibers. These findings underscore the role of pre-gelation in optimizing cellulose material properties for applications ranging from advanced textiles to biomaterials and sustainable packaging. Future research directions include further exploration of the structural and functional benefits of pre-gelation in cellulose processing and its broader implications in material science and engineering. [ABSTRACT FROM AUTHOR]

In this study, two green extraction methods are explored to valorize rice straw into cellulose fibers (CFs), namely subcritical water extraction (SWE) and combined ultrasound‐heating treatment (USHT). The resultant fibers are, thereafter, successfully pretreated with (3‐glycidyloxypropyl) trimethoxysilane (GPS) and incorporated at 3% wt into poly(butylene succinate) (PBS) by melt‐mixing. The green composites are shaped into films by thermo‐compression and characterized in terms of their performance for food packaging applications. The chemical analysis of the fibers reveals that SWE is more effective to selectively remove hemicelluloses than USHT, whereas silanization promotes the removal of lignin in both fiber types. Fiber incorporation, more notably in the case of the silanized fibers, restricts the movement of the PBS chains, indicating good interaction with the biopolyester matrix. In particular, CFs act as antinucleating agents in PBS, delaying both glass transition and crystallization from the melt phenomena and hindering crystal formation. Furthermore, the fibers mechanically reinforce and improve the oxygen barrier of the PBS films. The highest barrier enhancement is obtained for the thermo‐compressed composite film with silanized fibers obtained by SWE, yielding a decrease of nearly 20% in the permeability to oxygen versus the unfilled PBS film. [ABSTRACT FROM AUTHOR]

Sustainable functionalization of bacterial cellulose for cost‐effective bionanocomposites with desired properties has received growing attention in recent years. This article presents the results of work aimed at obtaining bionanocomposite materials based on bacterial cellulose, a natural and eco‐friendly material. Bacterial cellulose obtained from the Kombucha symbiotic culture of bacteria and yeast (SCOBY) fermentation process is functionalized by embedding with diatom frustules, silver nanoparticles (AgNPs), and poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS). The effects of functionalization on mechanical, optical, plasmonic, electrical, chemiluminescent, and antimicrobial properties are evaluated. Morphological characteristics of the nanocomposites are studied using electron microscopy. Addition of diatom frustules introduced into the SCOBY culture media results in bionanocomposite materials with enhanced tensile strength and increased ultraviolet (UV) blockage properties. In situ functionalization of bacterial cellulose with AgNPs tunes plasmonic and chemiluminescent properties, revealing the biosensing potential of the material. Modified bacterial cellulose shows antimicrobial activity in experiments with gram‐positive and gram‐negative bacteria. Dual functionalization of bacterial cellulose with PEDOT:PSS and AgNPs results in improved electrical conductivity of the bionanocomposite. Overall, bottom‐up physical functionalization approaches and the resulting bionanocomposite materials will open up new opportunities for the low‐cost production of green materials and contribute to the development of a sustainable economy. [ABSTRACT FROM AUTHOR]

This study investigates the effectiveness of various chemical methods, both ultrasound-assisted and non-assisted, for extracting cellulose from banana pseudostem (BPS) waste, comparing the results with commercial pine and eucalyptus cellulose fibers. Delignification treatments with NaOH (25% and 30%) and H2O2 (8%) were evaluated, applied with both conventional and focused sonication. Ultrasound-assisted methods, particularly with NaOH, achieved cellulose percentages as high as 99.5%. X-ray diffraction (XRD) analysis revealed that NaOH treatments significantly increased the cellulose crystallinity index, reaching up to 67.9%, surpassing commercial fibers. Scanning electron microscopy (SEM) results showed that NaOH treatments, especially at 30%, improved fiber morphology and exposure. Thermogravimetric analysis (TGA) indicated that methods using NaOH and focused sonication enhanced the thermal stability of the cellulose. Compared to commercial fibers, some samples obtained with the proposed methods demonstrated higher purity, yield, and thermal stability, highlighting the effectiveness of ultrasound-assisted and NaOH methods. [ABSTRACT FROM AUTHOR]

In this work, composites made of polylactide (PLA) and filled with alkali-pretreated rice husk (RH) were investigated. Composites containing 20, 30, and 40 wt.% of RH were synthesized. It was shown that alkaline treatment, along with the change in crystal lattice, led to an increase in the content of non-crystalline parts and the volume of intercrystalline spaces, and the internal surface of the cellulose fiber increased, which resulted in improved adhesion of the fiber with the matrix. The addition of rice husk to the PLA matrix led to an increase in the flexural modulus, which increased to 2881 MPa for the PLA/RH (80/20 wt.%) and 3034 MPa for the PLA/RH (70/30 wt.%) composites and lowered the peak load stress by approximately 43% for the composite with 20 wt.% RH and 56% for the composite with 30 wt.% RH. The reduction in the degree of PLA crystallinity allows macromolecules to move more freely in amorphous regions, which has a positive effect on increasing the flexibility of materials in general. The optimal formulation is a composite consisting of 30% RH and 70% PLA matrix. [ABSTRACT FROM AUTHOR]

Cellulose, a naturally abundant biopolymer, holds great potential as a sustainable alternative to synthetic fibers. However, the limited understanding and awareness surrounding cellulose utilization, particularly from agricultural origins, have impeded the complete harnessing of this highly biodegradable resource. This study aimed to extract and characterize cellulose from jute and banana fibers. The extracted cellulose exhibits a light yellow to white color, and microscopic analysis of the fibers showed micro‐fibrils. X‐ray diffraction (XRD) characterization indicated that the extracted cellulose from biomass primarily consists of cellulose II structures, except for the treated banana fiber (M:L = 1:8), which contains both cellulose I and II. Moreover, increasing the M:L ratio of alkali treatment enhanced the percentage of cellulose‐II, as observed from the XRD data. The findings of this study carry significant implications for the efficient production of cellulose fibers, with diverse applications spanning from high‐volume products like regenerated fibers, automotive parts, packaging, absorbent products (diapers), textiles, and precast concrete, drug delivery mediums, electronics, additive manufacturing, bone and tissue scaffolding, and so on. This research opens the door to harnessing the potential of cellulose derived from jute and banana fibers in various industries. Highlights: Extraction cellulose using the kraft process.Isolated cellulose shows a micron‐sized structure.Optimal extraction achieved with M:L ratio of 1:4.Applications of isolated cellulose: regenerated fibers, packaging, absorbent products (diapers), textiles, and so on. [ABSTRACT FROM AUTHOR]

Flotation deinking is one of the most widely used techniques for the separation of ink particles from cellulose fibers during the process of paper recycling. It is a complex process influenced by a variety of factors, and is difficult to represent and usually results in models that are inconvenient to implement and/or interpret. In this paper, a comprehensive study of several machine learning methods for the prediction of flotation deinking performance is carried out, including support vector regression, regression tree ensembles (random forests and boosting) and Gaussian process regression. The prediction relies on the development of a limited dataset that assumes representative data samples obtained under a variety of laboratory conditions, including different reagents, pH values and flotation residence times. The results obtained in this paper confirm that the machine learning methods enable the accurate prediction of flotation deinking performance even when the dataset used for training the model is limited, thus enabling the determination of optimal conditions for the paper recycling process, with only minimal costs and effort. Considering the low complexity of the Gaussian process regression compared to the aforementioned ensemble models, it should be emphasized that the Gaussian process regression gave the best performance in estimating fiber recovery (R2 = 97.77%) and a reasonable performance in estimating the toner recovery (R2 = 86.31%). [ABSTRACT FROM AUTHOR]

Combining cellulose‐based components with functional materials is highly interesting in various research fields due to the improved strength and stiffness of the materials combined with their low weight. Herein, the mechanical properties of opal films are improved by incorporating cellulose fibers and microcrystalline cellulose. This is evidenced by the increase in tensile strength of 162.8% after adding 10 wt% of microcrystalline cellulose. For this purpose, core–shell particles with a rigid, crosslinked polystyrene core and a soft shell of poly(ethyl acrylate) and poly(ethyl acrylate‐co‐hydroxyethyl methacrylate) are synthesized via starved‐feed emulsion polymerization. The synthesized particles' well‐defined shape, morphology, and thermal properties are analyzed using transmission electron microscopy, scanning electron microscopy, and differential scanning calorimetry measurements. Free‐standing mechanochromic opal films with incorporated cellulose and structural colors are obtained after processing the core–shell particles with cellulose via extrusion and the melt‐shear organization technique. The homogeneous distribution of the cellulose within the composite material is investigated using fluorescent‐labeled cellulose. The opal film's angle‐dependent structural color is demonstrated using reflection spectroscopy. [ABSTRACT FROM AUTHOR]

The discrimination of five subtypes of regenerated cellulose fibers, i.e., viscose, bamboo, lyocell, modal, and cupro, from both men's and women's clothing available on the prevalent apparel market was described. The examinations were conducted using optical microscopy (in transmitted white light and polarized light), scanning electron microscopy coupled with energy dispersive X-ray spectrometry (SEM–EDX), and Fourier Transform Infrared Spectroscopy (FTIR). The microscopic methods revealed characteristic features of the morphological structure of the examined fibers, enabling the identification of differences between the subtypes. As a result, the microscopic methods were found to be the most effective for identifying and distinguishing between the types of examined fibers. Although the FTIR technique did not allow for distinguishing between the fiber subcategories, it contributed to the enlargement of the IR spectra databases for regenerated cellulose fibers. Based on the findings, a general scheme of the procedure for identifying the tested fibers was proposed. [ABSTRACT FROM AUTHOR]