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Rhododendron ponticum (R. ponticum), a rapidly spreading invasive species in Ireland, was investigated for its potential use in creating sustainable bioproducts. This study explored the utilization of R. ponticum biomass as a source of microfibrillated cellulose (MFC) for fungal cultivation. The production of MFC was evaluated employing a novel cryocrushing treatment combined with a twin-screw extruder (TSE). The results demonstrated a significant increase in film strength, up to 332.3 MPa, with increasing TSE steps compared to 72.5 MPa in untreated samples. X-ray diffraction (XRD) analysis revealed a decrease in crystallinity from 68.93 % to 59.2 %, following cryocrushing and TSE treatment. Additionally, MFC subjected to the highest TSE treatment (12 steps) was successfully used as a substrate for cultivating Agaricus blazei mushrooms using 0.2 wt%, 0.5 wt%, and 1 wt% MFC over a period of 7 days. Fourier-transform infrared spectroscopy (FTIR) confirmed the presence of chitin/chitin glucan within the fungal fibers. This research highlights the potential for transforming the invasive R. ponticum into valuable biocomposite materials. These MFC-fungus composites hold promise for various applications, including sustainable packaging, biodegradable plastics, and eco-friendly textiles.

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This research paper aims to enhance the fatigue resistance of polylactic acid (PLA) in Material Extrusion (ME) by incorporating natural reinforcement, focusing on rotational bending fatigue. The study investigates the fatigue behavior of PLA in ME, using various natural fibers such as cellulose, coffee, and flax as potential reinforcements. It explores the optimization of printing parameters to address challenges like warping and shrinkage, which can affect dimensional accuracy and fatigue performance, particularly under the rotational bending conditions analyzed. Cellulose emerges as the most promising natural fiber reinforcement for PLA in ME, exhibiting superior resistance to warping and shrinkage. It also demonstrates minimal geometrical deviations, enabling the production of components with tighter dimensional tolerances. Additionally, the study highlights the significant influence of natural fiber reinforcement on the dimensional deviations and rotational fatigue behavior of printed components. The fatigue resistance of PLA was significantly improved with natural fiber reinforcements. Specifically, PLA reinforced with cellulose showed an increase in fatigue life, achieving up to 13.7 MPa stress at 70,000 cycles compared to unreinforced PLA. PLA with coffee and flax fibers also demonstrated enhanced performance, with stress values reaching 13.6 MPa and 13.5 MPa, respectively, at similar cycle counts. These results suggest that natural fiber reinforcements can effectively improve the fatigue resistance and dimensional stability of PLA components produced by ME. This paper contributes to the advancement of additive manufacturing by introducing natural fiber reinforcement as a sustainable solution to enhance PLA performance under rotational bending fatigue conditions. It offers insights into the comparative effectiveness of natural fibers and synthetic counterparts, particularly emphasizing the superior performance of cellulose.

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In this research, Aloe Vera Gel (AVG) was incorporated into Unsaturated Polyester Resin (UPR) with jute-cotton union fabric to fabricate partially biodegradable composites. These composites were fabricated using a hand lay-up technique and characterized using Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetry Analysis (TGA), thermal conductivity measurements, water absorption tests, degradation assessments, cracking tests, and Universal Testing Machine (UTM) analysis. The study found that increasing the percentage of AVG in the composites led to a decrease in thermal conductivity, indicating improved insulation properties. Samples reinforced with AVG showed enhanced resistance to damage from iron nails, with reduced scratching and fiber displacement observed. However, the addition of AVG resulted in decreased thermal, mechanical, and water resistance properties compared to composites without AVG. FTIR analysis demonstrated interactions between AVG and the matrix materials. In degradation tests, composites subjected to an alkali environment (PH = 11.96) showed the highest weight reduction (2.22 %) compared to those without AVG. Similarly, composites buried in soil exhibited greater weight loss (2.38 %) than their counterparts lacking AVG. Overall, the developed composite's reduced heat transfer rate suggests its potential application as an insulating material in environments such as rural poultry housing and the automotive industry.

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The anticoccidial monensin (MON) is a high-concern emerging pollutant. This research focused on six low-cost bio-adsorbents (alfa, cactus, and palm fibers, and acacia, eucalyptus, and zean oak barks), assessing their potential for MON removal. Batch adsorption/desorption tests were carried out, and the results were fitted to the Freundlich, Langmuir, Linear, Sips, and Temkin models. The concentrations adsorbed by the six materials were very similar when low doses of antibiotic were added, while they differed when adding MON concentrations higher than 20 µmol L-1 (adsorption ranging 256.98-1123.98 µmol kg-1). The highest adsorption corresponded to the sorbents with the most acidic pH (<5.5) and the highest organic matter and effective cation exchange capacity values (eucalyptus bark and acacia bark, reaching 92.3% and 87.8%), whereas cactus and palm fibers showed the lowest values (18.3% and 10.17%). MON desorption was below 8.5%, except for cactus and palm fibers. Temkin was the model showing the best adjustment to the experimental data, followed by the Langmuir and the Sips models. The overall results indicate that eucalyptus bark, alfa fiber, and acacia bark are efficient bio-adsorbents with potential for MON removal, retaining it when spread in environmental compartments, reducing related risks for human and environmental health.

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Losses in irrigation canals occur during the process of water transportation. In irrigation conveyance water losses, seepage loss is the main contributor to total water loss. The most problematic factors are cracks and settlement of the lined canal in canal lining structures. Water loss occurs in earth channels, mainly due to erosion and the permeability of the material. The concrete, as it does not present cracks, will have a less impermeable layer. Usually, seepage loss comprises 20-30% of the total water loss, and it can be reduced to 15-20% with canal linings. By enhancing the flexure and split tensile strength of concrete, the rate of cracking in the canal lining can be controlled. Concrete's split tensile strength is one of the most important factors in crack control. The behavior (compressive, flexural, and split tensile properties, water absorption, linear shrinkage mass loss, etc.) of hybrid polypropylene and jute fiber-reinforced concrete (HPJF-RC) for the application of canal linings was studied. In this experimental work, a total of nine mixes were made with different lengths and contents of hybrid polypropylene and jute fiber-reinforced concrete (HPJF-RC) and a control mix. The SEM analysis was performed to explore the hybrid fiber cracking mechanism and the bonding of fibers with the concrete. The crack arresting mechanism of the HPJF-RC will help to reduce water losses in concrete canal linings. With this modern material, the water losses in canal linings can be minimized. The results of this experimental work would be helpful as a reference for both industry experts and academic researchers interested in the advancement of HPJF-RC composites.

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In the present paper, we have conducted a comprehensive analysis of vapor pressures of both saturated and unsaturated solutions, alongside a study of evaporation using synthetic and natural fabrics for industrial applications in brackish water treatment under zero liquid discharge (ZLD) philosophy. By determining the vapor pressures of saturated solutions, we obtained results consistent with those of other researchers, extending the range of tested temperatures from 1 to 50 °C and successfully fitting the parameters of an Antoine-type equation. Similarly, positive results were achieved for unsaturated solutions, where various parameters of different equations accounting for the salt concentration were estimated, simplifying the fitting procedure. Natural evaporation tests from water surfaces using saturated solutions revealed that salts with higher associated vapor pressures exhibit higher evaporation rates. On the other hand, hydrated salts retain water in their structure and are significantly affected by ambient humidity. Evaporation studies on natural and synthetic fabrics with saturated NaCl and CuSO4·5H2O solutions showed distinct behaviors. NaCl increased both the evaporation rate and salt deposition with each cycle. In contrast, CuSO4·5H2O reduced the absorption capacity by blocking the fabric's structure, decreasing the evaporation efficiency over successive cycles.

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The current demand for composites reinforced with renewable fibers is greater than it has ever been. In comparison to glass fibers, natural fibers yield the advantages of lesser density and cost. Although comparable specific properties exist between glass and natural fibers, the latter shows lower strength. However, with the copper coating and chemical treatment of natural fibers, the strength of the composites can be increased nowadays. The current research investigation focuses on the life cycle assessment of the raw, chemically treated, and copper coated fiber reinforced bagasse and banana composites to compare the emissions on the environment of these samples to prove their applicability. The study includes all the processes, from the extraction of fibers to the formation of composites, i.e., from cradle to gate, and detailed inventory. The ReCiPe H midpoint method has been utilized in SimaPro software to quantify the emissions. The results indicate that the maximum global warming emission is due to the energy consumption used during the manufacturing of these composites. Electricity contribution for chemically treated and copper coated composites in global warming contribution is slightly greater than that of raw composites i.e., 73.275 % in C- BG/P, 73.06 % in Cu- BG/P, 73.65 % in C- BN/P and 74.28 % in Cu- BN/P which is comparatively higher than 63.8 % in R- BG/P and 64.97 % in R- BN/P. The next major contributions come from polylactic acid for all the three samples of bagasse fiber reinforced PLA composite and banana fiber reinforced PLA composite. The raw samples also show improved fiber strength compared to chemical and copper coated samples.

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In this study, we investigated the use of deep eutectic solvents (DESs) at different molar ratios and temperatures as a green and efficient approach for microfibers (MFs) extraction. Our approach entailed the utilization of Firmiana simplex bark (FSB) fibers, enabling the production of different dimensions of FSB microfibers (FSBMFs) by combining DES pretreatment and mechanical disintegration technique. The proposed practice demonstrates the simplicity and effectiveness of the method. The morphology of the prepared microfibers was studied using the Scanning electron microscopic (SEM) technique. Additionally, the results revealed that the chemical and mechanical treatments did not significantly alter the well-preserved cellulose structure of microfibers, and a crystallinity index of 56.6 % for FSB fibers and 63.8 % for FSBMFs was observed by X-ray diffraction (XRD) analysis. Furthermore, using the freeze-drying technique, FSBMFs in water solutions produced effective aerogels for air purification application. In comparison to commercial mask (CM), FSBMF aerogels' superior hierarchical cellular architectures allowed them to attain excellent filtration efficiencies of 94.48 % (PM10) and 91.51 % (PM2.5) as well as excellent degradation properties were analyzed. The findings show that FSBMFs can be extracted from Firmiana simplex bark, a natural cellulose-rich material, using DES for environmentally friendly aerogel preparation and applications.

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A validation of the factorial, Taguchi and response surface methodology (RSM) statistical models is developed for the analysis of mechanical tests of hybrid materials, with an epoxy matrix reinforced with natural Chambira fiber and synthetic fibers of glass, carbon and Kevlar. These materials present variability in their properties, so for the validation of the models a research methodology with a quantitative approach based on the statistical process of the design of experiments (DOE) was adopted; for which the sampling is in relation to the design matrix using 90 treatments with three replicates for each of the study variables. The analysis of the models reveals that the greatest pressure is obtained by considering only the source elements that are significant; this is reflected in the increase in the coefficient of determination and in the predictive capacity. The modified factorial model is best suited for the research, since it has an R2 higher than 90% in almost all the evaluated mechanical properties of the material; with respect to the combined optimization of the variables, the model showed an overall contribution of 99.73% and global desirability of 0.7537. These results highlight the effectiveness of the modified factorial model in the analysis of hybrid materials.

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Low-density green polyethylene (LDGPE) composites reinforced with 5 wt% of bamboo fiber and 3 wt% of a compatibilizing agent (polyethylene grafted with maleic anhydride and tannin) were processed through extrusion and injection molding. Bamboo fiber, Bambusa Vulgaris, was characterized using Fourier-transform infrared spectroscopy (FTIR). The molded specimens were analyzed for their thermal, mechanical, and morphological properties. The estimated concentration was chosen to provide the best mechanical strength to the material studied. FTIR analysis of the fibers revealed the presence of groups characteristic of bamboo fiber and tannin. Differential scanning calorimetry revealed that both compatibilizing agents increased the matrix's degree of crystallinity. However, scanning electron microscopy (SEM) showed that, despite the presence of compatibilizing agents, there was no significant improvement in adhesion between the bamboo fibers and LDGPE.

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This article summarizes findings in the field of the history, composition, and mechanical properties of WPCs (wood-plastic composites) formed by combining two homogeneous substances, i.e., a polymer matrix with cellulose fibers in a certain ratio (with the addition of additives). In relation to a wide range of applied natural reinforcements in composites, it focuses on wood as a fundamental representative of lignocellulosic fibers. It elucidates the concept of wood flour, the criteria for its selection, methods of storage, morphological characteristics, and similar aspects. The presence of wood in the plastic matrix reduces the material cost while increasing the stiffness. Matrix selection is influenced by the processing temperature (Tmax = 200 °C) due to the susceptibility of cellulose fibers to thermal degradation. Thermoplastics and selected biodegradable polymers can be applied as matrices. The article also includes information on applied additives such as coupling agents, lubricants, biocides, UV stabilizers, pigments, etc., and the mechanical/utility properties of WPC materials. The most common application of WPCs is in automotive sector, construction, aerospace, and structural applications. The potential biodegradability and lower cost of applications featuring composite materials with natural reinforcements motivated us to delve into this type of work.

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The development of bio-insultation materials has attracted increasing attention in building energy-saving fields. In tropical and hot-humid climates, building envelope insulation is important for an energy efficient and comfortable indoor environment. In this study, several experiments were carried out on a bio-insulation material, which was prepared by using rice husk as a raw material. Square rice husk-based insultation panels were developed, considering the ASTM C-177 dimensions, to perform thermal conductivity coefficient tests. The thermal conductivity coefficient obtained was 0.073 W/(m K), which is in the range of conventional thermal insulators. In a second phase of this study, two experimental enclosures (chambers) were constructed, one with rice husk-based insulation panels and the second one without this insulation. The measures of the temperatures and thermal flows through the chambers were obtained with an electronic module based on the ARDUINO platform. This module consisted of three DS18B20 temperature sensors and four Peltier plates. Daily temperature and heat flux data were collected for the two chambers during the dry season in Panama, specifically between April and May. In the experimental chamber that did not have rice husk panel insulation on the roof, a flow of up to 28.18 W/m2 was observed, while in the chamber that did have rice husk panels, the presence of a flow toward the interior was rarely observed. The rice husk-based insulation panels showed comparable performance with conventional insulators, as a sustainable solution that takes advantage of a local resource to improve thermal comfort and the reduction of the environmental impact.

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Embarking on a pioneering investigation, this study unravels the extraordinary qualities of Tecoma stans Fibers (TSFs), freshly harvested from the rachis, establishing them as prospective reinforcements for biocomposites. Delving into their intricate characteristics, TSFs exhibit a unique fusion of physical resilience, with a density of 1.81 ± 0.39 g/cc and a diameter of 234.12 ± 7.63 µm. Complementing their physical prowess, their chemical composition boasts a harmonious blend of cellulose (70.1 ± 9.06 wt%), hemicellulose (13.56 ± 4.29 wt%), lignin (7.62 ± 2.39 wt%), moisture (4.21 ± 1.56 wt%), wax (2.37 ± 0.63 wt%), and ash (1.25 ± 0.36 wt%). In the realm of mechanical strength, TSFs showcase an impressive tensile strength of 639 ± 18.47 MPa, coupled with a robust strain at failure of 1.75 ± 0.13 % and a Young Modulus of 36.51 ± 1.96 GPa. Unveiling their crystalline intricacies, these fibers reveal a microfibril angle of 14.66 ± 0.15°, a crystalline index (CI) of 63.83 %, and a crystallite size (CS) of 9.27 nm. Beyond their mechanical marvels, TSFs exhibit unwavering thermal stability, enduring temperatures up to 297.36 °C, with a Tmax reaching an impressive 392.09 °C.

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This study focuses on examining the influence of bast fibers on the flammability and thermal properties of the polylactide matrix (PLA). For this purpose, Urtica dioica and Vitis vinifera fibers were subjected to two types of modifications: mercerization in NaOH solution (M1 route) and encapsulation in an organic PLA solution (M2 route). In a further step, PLA composites containing 5, 10, and 15 wt% of unmodified and chemically treated fibers were obtained. The results of the tests show that only biocomposites containing mercerized fibers had a nearly 20% reduced flammability compared to that of PLA. Moreover, the biofiller obtained in this way belongs to the group of flame retardants that generate char residue during combustion, which was also confirmed by TGA tests. The M2 modification route allowed to achieve higher mass viscosity than the addition of unmodified and M1-modified fibers. The reason is that fibers additionally encapsulated in a polymer layer impede the mobility of the chain segments. The inferior homogenization of the M2-modified fibers in the PLA matrix translated into a longer combustion time and only a 15% reduction in flammability.

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This work aims to evaluate experimentally different fibers and resins in a topologically optimized composite component. The selected ones are made of carbon, glass, basalt, flax, hemp, and jute fibers. Tailored Fiber Placement (TFP) was used to manufacture the textile preforms, which were infused with two different epoxy resins: a partly biogenic and a fully petro-based one. The main objective is to evaluate and compare the absolute and specific mechanical performance of synthetic and natural fibers within a component framework as a base for improving assessments of sustainable endless-fiber reinforced composite material. Furthermore, manufacturing aspects regarding the different fibers are also considered in this work. In assessing the efficiency of the fiber-matrix systems, both the specific stiffness and the specific stiffness relative to carbon dioxide equivalents (CO2eq.) as measures for the global warming potential (GWP) are taken into account for comparison. The primary findings indicate that basalt and flax fibers outperform carbon fibers notably in terms of specific stiffness weighted by CO2eq.. Additionally, the selection of epoxy resin significantly influences the assessment of sustainable fiber-plastic composites.

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The use of natural fibers in cementitious composites has been gaining prominence in engineering. The natural lignocellulosic fibers (NLFs) used in these composites have advantages such as reduced density, reduced fragmentation and concrete cracking, thus improving flexural performance and durability. Coconut-fiber is one of those natural fibers and its use presents technical, ecological, social and economic benefits, as it is improperly disposed of, representing a large waste of natural resources, in addition to causing environmental pollution.. Thus, composites reinforced with natural fibers are promising materials for the construction industry, as in addition to meeting the sustainability of buildings, there will also be a reduction in urban solid waste generated and gains for structures with the use of environmentally friendly materials that meet to active efforts and with greater durability. This work aims to evaluate the tensile behavior of green coconut-fibers subjected to different drying temperatures through chemical, thermal (TG/DSC), morphological, visual and mechanical analysis. Drying temperatures of 70 °C, 100 °C and 130 °C were analyzed and the results indicated that the drying temperature at 70 °C was satisfactory, providing fiber-reinforced composites with good tensile strength, combined with good ductility.

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Natural fibers have garnered considerable attention owing to their desirable textile properties and advantageous effects on human health. Nevertheless, natural fibers lag behind synthetic fibers in terms of both quality and yield, as these attributes are largely genetically determined. In this article, a comprehensive overview of the natural and synthetic fiber production landscape over the last 10 years is presented, with a particular focus on the role of scientific breeding techniques in improving fiber quality traits in key crops like cotton, hemp, ramie, and flax. Additionally, the article delves into cutting-edge genomics-assisted breeding techniques, including QTL mapping, genome-wide association studies, transgenesis, and genome editing, and their potential role in enhancing fiber quality traits in these crops. A user-friendly compendium of 11226 available QTLs and significant marker-trait associations derived from 136 studies, associated with diverse fiber quality traits in these crops is furnished. Furthermore, the potential applications of transcriptomics in these pivotal crops, elucidating the distinct genes implicated in augmenting fiber quality attributes are investigated. Additionally, information on 11257 candidate/characterized or cloned genes sourced from various studies, emphasizing their key role in the development of high-quality fiber crops is collated. Additionally, the review sheds light on the current progress of marker-assisted selection for fiber quality traits in each crop, providing detailed insights into improved cultivars released for different fiber crops. In conclusion, it is asserted that the application of modern breeding tools holds tremendous potential in catalyzing a transformative shift in the textile industry.

Natural fibers possess desirable properties, but they often lag behind synthetic fibers in terms of both quality and quantity. Genomic-assisted breeding has the potential to improve fiber quality traits in cotton, hemp, ramie, and flax. Utilizing available QTLs, marker-trait associations, and candidate genes can contribute to the development of superior fiber crops, underscoring the significance of advanced breeding tools.

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Short flax fibers have been modified by radiation-induced grafting using methacrylate monomers containing phosphorus to give them a flame-retardant character. Two methodologies, namely pre-irradiation and simultaneous irradiation grafting, were examined. Certain parameters, notably the dose and the irradiation source (e-Beam and γ rays), were evaluated. The grafting efficiency, in terms of phosphorus content (mass percentage), was measured by X-ray fluorescence spectrometry (XRF). Using simultaneous irradiation, 2.39 wt% phosphorus could be obtained from 10 kGy, compared to 100 kGy in pre-irradiation. Furthermore, for similar phosphorus levels, the location of the grafted polymer chains was different for the two methodologies. The effect of phosphorus content on thermal properties and fire behavior was evaluated on a microscopic scale using a pyrolytic flow combustion calorimeter (PCFC) and on a laboratory scale using a cone calorimeter. It was then pointed out that flammability was linked to the phosphorus content and likely its location, which is associated with the radiation-induced grafting methodology, showing that the grafting conditions influence the final fire properties. Simultaneous irradiation, thus, proved to be more interesting in terms of efficiency and final properties.

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Intelligent and green wearable technology becomes essential for new modern societies. This work introduces a multi criteria decision making model to properly assess and compare relative desired criteria for selecting the most suitable constituents for green body wearable bio-products made from bio-based materials. It aims to enhance the sustainability of intelligent green wearable devices by providing support in the selection process of lightweight, eco-friendly materials suitable for personal body wearable bio-products made of natural fiber composites to improve qualities that may help in better monitoring human vital signs and thereby address the health care concern. The relative intrinsic characteristic and merits of various natural fibers were utilized to compare and evaluate their relative performance in bio-composites. The model considered several evaluation factors like mechanical performance including tensile strength and modulus of elasticity, comfortability including size and weight, availability, fiber orientation, cellulose content, and cost. Results have demonstrated different priorities of the considered natural fibers relative to each evaluation factor. However, the model was capable of properly evaluating and ranking the best fibers relative to the whole conflicting evaluation criteria simultaneously. The closeness of priorities in several cases emphasizes upon using such decision making models to be able to judge the relative merits of natural fibers for such applications. It can also help designers to avoid bias during determining the best alternatives considering several conflicting evaluation criteria.