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This study offers design of the 'socially optimal' rebate and tax structures, corresponding to the maximum expected gain and minimum risk from migration of prospective risk-averse suppliers towards supplying sustainable products. Risk-averse behaviour is caused by small and medium-sized suppliers who are financially constrained from the perspective of a textile company. This study addresses the unexplored but serious issue of suppliers' willingness-to-pay for renouncing the option of migrating towards sustainable practices under uncertain market conditions for sustainable products, by using a mean-variance utility framework. The analytical model is validated using case-based real data collected from an Indian retailer who works with two types of suppliers in India: one natural fibre supplier and another chemical-based synthetic fibre supplier. Our model helps explain the effects of loss in expected market share and sudden increase in variability in market share for sustainable products respectively on the 'socially optimal' rate of tax and rebate. Also, we establish that with rate of tax increases, the 'socially optimal' rate of rebate on sustainable product must increase at an increasing rate to induce potential migration of suppliers towards sustainable practices. The implications of our findings on academics and practice are offered. [ABSTRACT FROM AUTHOR]

The "New Journal of Chemistry" published by the Royal Society of Chemistry features a variety of research papers on topics such as bioelectrocatalysis, photovoltaic properties, and electrochemical studies. The journal aims to connect the global chemistry community through high-impact publications and training courses. The articles cover a range of subjects, including the synthesis of materials for energy applications, catalysis, and optical properties of compounds. [Extracted from the article]

New design techniques are required to improve the stability of vitamin C (VC), which is essential for human health but is sensitive to environmental factors, in the stomach and its release in the body. The purpose of this study is to develop and characterise a fibre interlaced liposome (FIL) as a vehicle for better delivery of VC, with fruit fibres providing surface protection against degradation, which was confirmed by various studies. The optimised formulation was evaluated for its structural and surface morphological properties through zeta potential, FTIR, XRD, SEM, TEM, and DSC analyses. In vitro release studies were also conducted, and FIL-VC displayed a sustained release of VC (19.31%) compared to the control (67.54%) during the period of 8 h. FIL-VC demonstrates better release in simulated intestinal fluids (95.34%) than in gastric fluids (21.15%), indicating better stability and absorption in the gastrointestinal tract. In a randomized, double-blind, active-controlled, two-way crossover clinical study, FIL-VC showed 5.77-fold higher relative oral bioavailability in comparison with the unformulated VC. The AUC0−t for VC in FIL-VC (23.80 μg mL−1) was found to be significantly higher compared to unformulated VC (4.13 μg mL−1) after the oral administration of a single dose. These data show that FIL formulation resulted in a sustained release of VC with increased bioavailability, which could be beneficial for extended-release applications. [ABSTRACT FROM AUTHOR]

This paper explores the production and mechanical analysis of hemp bi-grid cores designed for use in sandwich structures, using an ad hoc continuous manufacturing process. The proposed customised manufacturing process allows for the production of cores with varying density values (ranging from 0.37 to 0.63 g/cm3). Both graded cores, with varying fibre content through the thickness, and non-graded cores were produced. The mechanical properties of these cores were evaluated under flexural and compressive testing with specific flexural strength reaching approximately 80 MPa·cm3/g and specific compressive elastic modulus around 340 MPa·cm3/g. Additionally, to assess their impact performance in sandwich panels, hybrid panels with CFRP skins were fabricated and subjected to Low Velocity Impact tests at 25 J, 45 J and 50 J. The results revealed that optimizing core density had increasingly beneficial effects as the impact energy increased. These findings suggest that the possibility of customising failure modes and tailor energy absorption capabilities of the proposed structures open the way for new, exciting perspectives for the development of innovative sandwich structures, broadening the application of natural fibres in various industrial sectors. [ABSTRACT FROM AUTHOR]

Highlights Using natural fibers in bio‐based product development offers a promising path toward an environmentally sustainable future. This study aims to characterize natural fibers obtained from food processing companies and artisans across Colombian regions, employing a methodology that can be extended to natural fibers characterization worldwide and supporting research focused on sustainable product development based on natural fibers. The thermal, mechanical, morphological, and surface properties of the fibers were measured using advanced techniques such as dynamic mechanical analysis‐DMA, thermogravimetry‐TGA, computed microtomograph, and 3D‐microscopy. The chemical composition was analyzed using Van Soest methodology and TGA thermogram deconvolution. Thermal characterization reveals that natural fibers start their degradation between 227 and 258°C, defining a safe thermal processing range for natural fiber‐reinforced polymer composites (NFRPC) products. Mechanical properties were measured at temperatures ranging from −50 to 150°C. Among the tested fibers, pineapple leaf fibers, hemp fibers, and toquilla straw exhibited superior mechanical performance up to 100°C suggesting their potential for developing bioproducts across various applications. In contrast, banana and coir coconut fibers showed lower tensile strength and tensile modulus. Surface roughness differs in the longitudinal and transverse directions, suggesting that chambira straw (Ra 0.067 mm), fique fibers (Ra 0.03 mm), and hemp and pineapple leaf fibers (Ra 0.021 mm) may be of interest for further investigation in NFRPC production. This research highlights the progress and challenges in utilizing natural fibers to develop sustainable products. It positively impacts regional economies, drives technological advancements, and expands the potential applications of natural fiber‐reinforced composites. Novel micro‐CT technique reveals accurate cross‐sectional areas of natural fibers Colombian natural fibers maintain stable tensile properties from −50 to 125°C Toquilla straw shows highest strength‐to‐density ratio among studied fibers Thermal analysis offers rapid verification of natural fiber chemical composition Ashby charts allow comparison of natural fibers and their uses in composites. [ABSTRACT FROM AUTHOR]

This study evaluated the influence of adding borosilicate residue (BS) as a flame retardant in polypropylene (PP) and natural fiber composites. The natural fibers used in this study come from the residue of the carpet industry, which is composed of PP and jute fibers (JT), while the PP used as the polymer matrix is postindustrial recycled material. The composites were produced by corotational twin‐screw extrusion and injection molding to obtain the test specimens. A coating process was carried out to add the water‐soluble fraction of BS to the surface of the compositions that did not receive it through incorporation during processing. To characterize the composites, flammability tests, thermogravimetric analysis (TGA), tensile strength test, and morphological analysis by scanning electron microscope (SEM) were performed. The addition of only 2 wt% BS content induces an increase in thermal stability of 32 and 109°C for composites with and without natural fibers, respectively. The addiction of 20 wt% BS elevates the elastic modulus up to 27% of the composites with and without natural fibers. The BS characterization indicates that it could be applied as a flame retardant when applied as coating methods using the water‐soluble fraction of BS, reducing the burning rate up to 92%. Flammability results are similar for formulations with and without natural fibers, indicating that the natural fibers did not influence the proposed flame retardant. The findings suggest that BS coating is a potential solution to improve the properties of natural fiber‐reinforced polymer composites while also promoting waste recycling. This approach produces composites with improved flammability, thermal stability, and mechanical properties, making them suitable for various end applications. [ABSTRACT FROM AUTHOR]

The use of waste‐based bio‐fillers in composite manufacturing has increased in recent years due to their sustainable and biodegradable characteristics. The current study fabricates jute/banana (JB) fiber‐reinforced epoxy composites incorporating waste‐derived eggshell (ES) bio‐filler and investigates the effect of ES bio‐filler on the mechanical, morphological, and water absorption properties of the composites. JB fibers (1:1) and varying ES filler contents (5, 10, 15, and 20 wt%) were used to manufacture the composites using the hand lay‐up technique. Their tensile, flexural, and impact properties, microstructure, chemical compositions, and water absorption are then examined. It is found that the composite composed of 15 wt% ES exhibits better tensile and flexural properties with a tensile modulus and strength of 4.42 GPa and 95.27 MPa, and a flexural modulus and strength of 3.96 GPa and 117.47 MPa, respectively, whereas the composite filled with 5 wt% ES shows a maximum impact strength of 46.83 kJ/m2 and drops with increasing bio‐fillers. Scanning electron microscopy reveals that composite failures occur due to jute and banana fiber fractures, filler–fiber‐matrix debonding, fiber pullout, and ES filler agglomeration. Moreover, water absorption reduces as the ES content rises, and the 20 wt% ES filler‐based composite shows a minimum water absorption of 7.67% after 240 h. This study provides some insights to promote the usage of ES bio‐filler in natural fiber composites to improve their mechanical and water absorption properties and their potential applications in the internal structures of automobiles, aircraft, and construction. [ABSTRACT FROM AUTHOR]

The development of eco-friendly materials is a challenging one in the research field. Natural fibers are more accessible, biodegradable, inexpensive, and less dense. They offer fewer health risks and are eco-friendly compared to synthetic fibers. Natural fiber-reinforced polymer composites are new, eco-friendly materials with excellent mechanical and practical applications. Adding biofillers to composites improves strength and will replace synthetic materials. Utilizing cellulose as a filler for a natural starch matrix is an effective way to reduce the environmental impact of non-biodegradable materials. This study covers the influence of natural Borassus flabellifer flower microcrystalline cellulose (BFF MCC) fillers on banana fiber-reinforced polymer matrix composites. Fourier-transform infrared spectroscopic peaks at 2357, 1730, and 1245 cm-1 were absent. This indicates that the amorphous proportion of banana fiber mat/BFF MCC-reinforced hybrid composites decreased. At 1% BFF MCC, thermogravimetric examination revealed an increase in the peak temperature of maximum degradation (389.6 °C). The hybrid banana composite's tensile strength (31.36 ± 4.39 to 39.83 ± 3.07 MPa) and flexural strength (71.05 ± 2.66 to 82.4 ± 1.66 MPa) were also improved after adding 3% BFF MCC as filler material. The primary objective is to evaluate the suitability of fiber-reinforced hybrid polymers with natural fillers for future engineering applications such as automotive parts, construction materials, 3D printing, etc. In addition, this study investigated how the reinforcement of microcrystalline cellulose can result in a material with enhanced performance as well as its mechanical characteristics (XRD, FTIR, TGA, and SEM characterization). [ABSTRACT FROM AUTHOR]

The growing demand for cotton and the low production rate required to meet global demands have encouraged viscose manufacturing from renewable sources. This work develops a sustainable method to extract viscose fibers (cellulosic‐based precursor) from jute, a renewable resource. Jute fiber is the second largest fiber crop in southern Asia, which contains 65%–70% cellulose and contributes to environmental benefits such as oxygen production, carbon dioxide emission, and heavy metal absorption during harvesting. The treated jute fiber was modified to regenerated cellulose (viscose), as confirmed by different characterizations. The Fourier‐transform infrared spectroscopy (FTIR) test 1423, 1365, 1033, and 1021 cm−1 represented that modified jute fiber resembled viscose fiber, and TGA attributed the thermal stability of glass transition below 100°C and thermal degradation to jute viscose fiber. XRD analysis provides a crystal index of 91.79% of viscose from jute fiber, which is higher than the 76.06% crystal index of raw jute. Here, SEM and physiomechanical properties were also characterized by raw jute and viscose from jute fiber. [ABSTRACT FROM AUTHOR]

The conversion of waste into value‐added products is critical to long‐term sustainability as waste disposal costs, landfilling space, and climate change would be reduced. Research and production industries investigate the possible use of natural fibers as a substitute for fossil fuels. Natural fiber‐reinforced polymer composites' physical and mechanical properties can be altered by natural fiber treatment, and the treatment choice relies on the desired properties and performance. In addition to cost‐profitability, environmental effects, and required performance, composites can be designed based on the product conditions. Disadvantages such as incompatibility of the hydrophilic natural fiber reinforcements with the hydrophobic polymer matrix often result in the tendency of the composite to have high moisture absorption, poor thermal stability, crystallinity, and mechanical strength. These factors critically impair the performance of the natural fibers as reinforcements in polymer composites, hence resulting in less‐favourable mechanical and physical properties. Physical, chemical, and biological treatments were examined to determine their effect on the durability and thermal, physical, and mechanical properties. It was observed that plasma treatment for bamboo fibers resulted in interfibral spaces and anchoring mechanisms between the resin and fibers, leading to increased load transfer. Chemical treatment at various concentrations improved the surface smoothness. The best mechanical, physical, thermal, and chemical properties for application as reinforcement in polymer composites were obtained at 6% for alkali treatments. Enzymatic treatment showed a significant impact on the impact and flexural strength of the composites. Factors such as duration, concentration, and extent of treatment need to be established for effective treatment, as prolonged treatments may damage the NFs' properties. This review comprehensively highlights the potential utilization of current natural fiber treatment methods for the potential of natural fibers as value‐added products for construction materials, considering their economical affordability, production of lightweight materials, sustainability, utilization of readily available waste material, and nature preservation. Furthermore, the three natural fiber treatment approaches for improving fiber‐matrix adhesion are discussed. The physical and mechanical properties of composites are highlighted, which aids in evaluating suitability for construction materials. [ABSTRACT FROM AUTHOR]

The requirement of excellent flexural stiffness in construction elements has initiated the use of fibre reinforcement. However, the processing complexity involved in the manufacture of synthetic fibres is environmentally hazardous. The use of natural fibres in geopolymer concrete (GPC) structures was investigated in this work using a hybridisation of natural and synthetic fibre. Natural basalt fibre (BF) was used with synthetic steel fibre (SF) in various proportions in GPC and tests were conducted to evaluate the workability, compressive strength, split tensile strength and flexural strength. It was found that, compared with the plain GPC, the addition of 1.5% BF and 0.5% SF resulted in 45%, 27% and 12% improvements in compressive, split tensile and flexural strengths, respectively. The compatibility between the SF and BF resulted in enhanced post-peak flexural behaviour, with 37% improvements in the modulus of elasticity and stiffness. As BF possesses more tensile strength than SF, the use of 1.5% BF and 0.5% SF provided better flexural and ductility properties than the use of SF alone, which could lead to the development of ductile GPC members under dynamic loading conditions. [ABSTRACT FROM AUTHOR]

In the current work, the dynamic and buckling properties of hybrid fiber-reinforced polymer composite beams are investigated. The hybrid composite beam is made of polyester matrix, carbon fiber, and jute fiber. The mechanical characteristics of carbon/jute/polyester composites were examined using ASTM standards. Experimental dynamic analysis was performed on jute, carbon, and hybrid carbon/jute composite beams. The validity of a finite element (FE) model based on higher-order theory was examined, and it exhibits outstanding agreement for composite beams when compared to experiments and literature. The hybrid composite beams have a considerable impact on structural stiffness when compared to neat jute/polyester composite beams. In this work, the effects of end conditions, taper angles, and composite layers are also investigated in relation to the dynamic and buckling properties of uniform and tapered hybrid carbon/jute/polyester composite beams. The findings imply that hybrid composites can be a superior substitute material for automotive applications. [ABSTRACT FROM AUTHOR]

AbstractSeveral studies focus on enhancing soil strength through the incorporation of natural or synthetic fibers. However, there is limited published data on the effectiveness of rice husk in soil reinforcement. The use of rice husk as a reinforcing material is supported by the fact that rice is one of the most produced and consumed cereals globally. In this article, we analyze the behavior of a clayey soil from southern Brazil with the addition of 0.5, 0.75, and 1% rice husk (RH), comparing it to coconut coir (CC) and curauá fibers (CU). In unconfined compressive strength tests (UCS), increases in soil strength of 20, 40, and 140% were observed for RH, CC, and CU, respectively, compared to pure soil. From consolidated undrained triaxial compression tests, both unreinforced soil and soil reinforced with 1% RH, CC, and CU were examined. The triaxial tests revealed an increase in the internal friction angle of 72 and 98%, alongside a decrease in cohesion of 57 and 94% due to the addition of CC and CU, respectively, in terms of effective stress. In contrast, RH did not significantly enhance the soil’s behavior, likely due to its shorter fiber length. [ABSTRACT FROM AUTHOR]

Basalt-based natural fiber hybrid composites with fillers are always the most anticipated composite material candidates for lightweight structural applications. Current work focusses on the preparation, characterization and testing of Basalt (B)/Hibiscus vitifolius (HV) based epoxy biocomposites with and without cashew nutshell fillers. Individual fiber reinforced composites (with 40 vol% of fibers) and hybrid composites (with 40 vol% of fibers in the ratio 1:1) filled with 10–30 vol% of fillers were manufactured using compression moulding techniques. The X-ray diffraction spectrum showed the crystal size and crystallinity index for all biocomposites. It showed a monoclinic crystal structure with an irregular surface of the fiber and filler. The FTIR spectrum showed the chemical composition presented in the biocomposites. The presence of filler and fibers was confirmed by different spectral peaks. Hybrid biocomposites were then subjected to mechanical and thermal investigations. The mechanical properties of the biocomposites showed that the tensile, flexural, and impact strength of the biocomposites varies with the concentration of the cashew nutshell filler. The surface morphology of the fractured sample showed the presence of fabric layer, fiber fracture and pull out, and homogenous dispersion of the fillers in the biocomposites. Thermal degradation curves showed that the thermal stability of biocomposites is improved by adding filler up to 20 vol% because the filler acted as a barrier element for the thermal degradation of biocomposites. From the results, it could be understood that these biocomposites find their applications probably in lightweight structures. [ABSTRACT FROM AUTHOR]

Natural plant fiber‐based packaging materials emerges as sustainable alternatives to conventional plastic and non‐biodegradable packaging. This paper presents an extensive review of the current technological status quo and commercial applications of natural plant fiber‐based packaging such as fiber‐based foams, molded pulp packaging, fiber‐based bottles, fiber‐based flexible packaging, fiber‐based blister packaging and stretchable paper. It focuses on the manufacturing processes and newest technology advancement of environmentally sustainable materials, meanwhile, the currently industry‐leading, cutting‐edge commercial products also are discussed. In conclusion, the paper advocates for the pivotal role natural plant fiber‐based packaging plays in transforming the packaging industry, addressing waste reduction, resource conservation, and climate change. It encourages the wider adoption of these materials while acknowledging the complexities involved and the need for continuous research and development to ensure their viability and effectiveness in meeting stringent packaging requirements. [ABSTRACT FROM AUTHOR]

Highlights The automotive, aerospace, and sports industries are increasingly utilizing hybrid composites made from natural fiber reinforcements. This study evaluated the performance of a composite made from kenaf and pineapple fibers, manufactured using the compression molding process, with graphene nanoparticles added at varying weight concentrations of 0.5, 1.0, 1.5, and 2.0 wt%. Results showed that adding 0.5 wt% graphene increased the tensile, flexural, and impact strength of hybrid composite by 133.75%, 90.24%, and 25.67%, respectively. Microstructural analysis revealed that graphene integration has enhanced the interfacial bond between the fiber and the matrix, creating resin‐rich areas. Furthermore, the free vibrational analysis indicated that graphene‐infused composites exhibited higher natural frequencies, improving their energy‐absorbing capabilities. Water absorption tests demonstrated that the inclusion of graphene reduced water penetration by improving interfacial bonding, minimizing voids, and decreasing surface energy, which limited water pathways in the composite. Furthermore, the composites with 0.5 wt% graphene showed a contact angle of 80.8°, indicating lower hydrophilicity compared to neat composites, which had a contact angle of 70.7°. This research emphasizes the advantages of hybrid composite materials derived from kenaf and pineapple fibers, specifically for applications in vehicle interiors and construction, including wall panels and separators. Hybrid composite was prepared using the compression molding process. Adding 0.5 wt% graphene improved the mechanical properties of composites. Hybrid composites with lower wt% graphene had higher natural frequencies. The composites with 0.5 wt% graphene had better water absorption properties. [ABSTRACT FROM AUTHOR]

Polylactic acid, a biodegradable thermoplastic derived from renewable sources, has notable environmental advantages and versatile properties. However, recycled PLA often experiences reduced mechanical strength and altered chemical composition due to the recycling process, limiting its suitability for 3D printing filament applications. Recognizing the inherent limitations of recycled PLA (rPLA), this research employs a unique method of coating rPLA with dopamine (DA) and reinforcing it with kenaf fibers (KF) at various weight fractions, introducing a novel multiscale modeling approach to address the challenges of interfacial bonding and tensile performance in recycled polymers. The methodology integrates experimental single filament tensile testing with multiscale finite element modeling to accurately predict the composite’s mechanical behavior across different scales. The findings reveal that a 5% kenaf fiber weight/volume fraction provides the optimal balance between tensile strength, stiffness, and toughness, achieving a significant 49.3% improvement over the unreinforced rPLA. However, increasing the kenaf fiber content beyond 5% leads to a decline in mechanical properties, attributed to higher fiber agglomeration and suboptimal fiber-matrix interactions. The novelty of this research lies in its combined use of PDA coating, natural kenaf fiber reinforcement, and advanced multiscale modeling to enhance and predict the performance of rPLA-PDA/kenaf composites, paving the way for sustainable, high-performance materials in 3D printing applications. [ABSTRACT FROM AUTHOR]

Highlights This study presents a novel equation that obtains the intrinsic flexural modulus of a natural fiber from its microfibril angle (MFA) and its crystalline cellulose content, once having estimated both parameters from X‐ray diffraction (XRD). The percentage of crystalline cellulose was estimated as the content of cellulose times the crystallinity index. Moreover, the MFA of abaca strands was obtained through an equation relating MFA with the strain at break of the strands and by XRD azimuthal integration, obtaining similar results. Fully bio‐based composites, consisting of biopolyethylene reinforced with of abaca strands at 20 to 50 wt% contents, were tested to assess the impact of the natural fibers on the flexural modulus of the composites. The intrinsic flexural modulus was also evaluated by using three micromechanics models (Hirsh equation, Halpin and Tsai equation, and its modification by Nielsen). The values obtained from the application of the new equation, the micromechanics methods, and the literature showed satisfactory agreement. Evaluation of the flexural modulus of abaca strand reinforced bio‐polyethylene composites. Use of micromechanics models to obtain the intrinsic modulus of abaca strands. Formula that correlates the intrinsic flexural modulus of abaca to its crystalline cellulose content and microfibril angle. [ABSTRACT FROM AUTHOR]

Hybrid kenaf/glass fiber reinforced polymer composites have emerged as promising structural materials, garnering significant attention due to their unique blend of natural kenaf fibers and synthetic glass fibers. However, despite their potential, there remains a gap in the comprehensive understanding of their quasi‐static mechanical behavior, creep resistance, and fatigue performance. This paper addresses this gap by presenting recent advancements in studying these key properties of hybrid composites. Studies reveal that the combination of kenaf and glass fibers results in enhanced tensile, flexural, and impact strengths compared to individual fiber composites. Additionally, the hybridization offers improved creep resistance, with the glass fibers reinforcing the polymer matrix against deformation under sustained loads. Furthermore, investigations into fatigue properties demonstrate the resilience of hybrid composites to cyclic loading, contributing to prolonged service life in high‐stress environments. By elucidating the interplay between kenaf and glass fibers, this review underscores the potential of hybrid composites in various structural applications. The synergistic effects between natural and synthetic fibers offer a balance between sustainability, performance, and durability, making hybrid kenaf/glass fiber reinforced polymer composites a compelling choice for industries seeking lightweight, high‐performance materials in which aligns with the sustainable development goals (SDGs) especially on Goal 12. Highlights: In composite engineering, combining glass and kenaf fibers could cut production costs, yield high‐performance materials, and promote green technology.Substituting part of the glass fiber with kenaf can enhance the strength‐to‐weight ratio and promote greater biodegradability in current synthetic composites.Quasi‐mechanical properties of hybrid kenaf/glass‐based composites was enhanced by optimal stacking sequences, filler addition, and fiber treatment.Failures due to fatigue and creep can be reduced by hybridizing kenaf/glass fiber composites can prevent in polymer composite due to enhance elastic modulus.Enhanced tribological performance of hybrid kenaf/glass‐based composites due to less damage in microstructure via good interlocking of kenaf and glass in matrix. [ABSTRACT FROM AUTHOR]

Highlights Hybrid composites have attracted considerable interest from researchers due to their balanced combination of ecological and mechanical properties. This paper examines the physical and mechanical behavior of hybrid composites reinforced with nano‐silica and woven jute/kenaf fiber. The hybrid composites were fabricated using hand layup techniques with varying weight percentages of nano‐silica (1.5, 3, 4.5, and 6 wt%) and three different fiber layering sequences (JKJK, JKKJ, and KJJK). The mechanical properties, including tensile, flexural, interlaminar shear strength, impact resistance, and hardness, along with the physical properties such as density and moisture absorption, are evaluated for the fabricated composite samples. The jute/kenaf composite fabricated with KJJK layering sequence and 4.5 wt% nano‐silica particles exhibited reduced void content (1.983%) and low moisture absorption (4.87%). The addition of 4.5 wt% nano‐silica to KJJK composites achieved a maximum tensile strength of 86.38 ± 2.9 MPa and a maximum tensile modulus of 4.238 ± 0.094 GPa. In KJJK hybrid composites, the incorporation of 4.5 wt% nano‐silica led to a 70.11% increase in flexural strength and a 47.05% increase in flexural modulus. Surface morphological analysis of the specimens was conducted using SEM to examine cracks, fiber pullout, and different failure modes within the hybrid composite. Developed the jute/kenaf composites with 1.5, 3, 4.5, and 6 wt% of nano‐silica. Nano‐silica into jute/kenaf composites reduced void content and moisture absorption. The composites with 4.5 wt% nano‐silica had better mechanical properties. Layering sequence jute and kenaf affect the mechanical properties. Morphological analysis confirms the improved adhesion with nano‐silica. [ABSTRACT FROM AUTHOR]

Highlights In recent years, natural fibers have been commonly used to reinforce various polymers, resulting in composites with excellent mechanical properties. To address the challenge of delamination and significant fiber pull‐out in inter‐laminar hybrid composites during stretching, this study focused on preparing intra‐laminar hybrid textile composites using basalt fibers (BFs) and jute fibers (JFs) as raw materials. Moreover, the mechanical properties of BF/JF intra‐layer blended fabric composites were investigated. The prepared composites underwent tensile, flexural, impact, and dynamic mechanical analysis (DMA). The results indicated that intra‐laminar blended composites demonstrated superior mechanical properties compared to inter‐laminar blended fabric composites. The DMA results revealed that the intra‐laminar blended composites featured a high peak loss factor. Morphological analysis indicated enhanced stress transfer from fiber‐to‐fiber and fiber‐to‐matrix in the intra‐laminar blended composites. Fiber blending can expand the application areas of natural fibers. Fiber blending can reduce interlayer damage. Intra‐layer blending differs from interlayer hybrid composites. Strong bonding between fibers facilitates effective stress transfer. “Green” composites exhibit exceptional mechanical properties. [ABSTRACT FROM AUTHOR]

Highlights This paper investigates how combining natural and synthetic fibers within yarns, altering the degree of hybridisation, and varying weave architectures affect the homogenized elastic properties and stress distributions in 2D woven composite laminae using a two‐scale homogenization scheme. The novelty lies in integrating a micro‐scale representative volume element model with a meso‐scale repeating unit cell model to capture intra‐yarn natural/synthetic fiber hybridisation. The study focuses on 2/2 twill and 5‐harness satin woven laminae with flax/E‐glass, hemp/E‐glass and basalt/E‐glass hybrid yarns, all with a total fiber volume fraction of 0.6. Fiber distributions are created through a random sequential expansion algorithm for hybrid RVEs, while periodic meso‐structures are used to define weave architectures for RUCs. Results show that yarn‐level fiber hybridisation significantly influences matrix stress distributions, with variations of up to 22%. In contrast, weave architecture has a minimal effect, with variations in homogenized properties below 2%. Varying fiber types, degrees of hybridisation and weave architectures allow for the tailoring of yarn and lamina properties and altering the stress distributions at micro‐ and meso‐scales and potentially influencing damage mechanisms. The modeling approach for analyzing the mechanical behavior of intra‐yarn hybrid natural/synthetic woven laminae could potentially be used to tailor their tolerance to damage. Two‐scale homogenization integrates RVE and RUC for 2D woven hybrid composites. Analyzed flax/E‐glass, hemp/E‐glass, basalt/E‐glass in twill and satin weaves. Intra‐yarn hybridisation significantly affects properties and stress fields. Hybridizing fibers offers tailored properties and may improve damage tolerance. [ABSTRACT FROM AUTHOR]

Natural fiber-reinforced biocomposites offer sustainable alternatives to conventional plastics. This study investigates the development of biocomposites using coconut spathe fiber, a renewable byproduct, reinforced with corn starch and poly(vinyl alcohol). The composites demonstrated significant mechanical properties, including a tensile strength of 46.8 MPa, flexural strength of 42.1 MPa, and an impact strength of 11.2 kJ m−2. Water absorption was limited to 33.6% after 24 hours, indicating hydrolytic stability. Biodegradation tests confirmed the complete breakdown of the material in composting conditions. These findings highlight the potential of coconut spathe-based biocomposites for applications in the automotive and packaging industries, addressing the need for sustainable and biodegradable materials in place of non-degradable thermoplastics. [ABSTRACT FROM AUTHOR]

Cultivated cotton plants are the world's largest source of natural fibre, where yield and quality are key traits for this renewable and biodegradable commodity. The Gossypium hirsutum cotton genome contains ~80K protein-coding genes, making precision breeding of complex traits a challenge. This study tested approaches to improving the genomic prediction (GP) accuracy of valuable cotton fibre traits to help accelerate precision breeding. With a biology-informed basis, a novel approach was tested for improving GP for key cotton fibre traits with transcriptomics of key time points during fibre development, namely, fibre cells undergoing primary, transition, and secondary wall development. Three test approaches included weighting of SNPs in DE genes overall, in target DE gene lists informed by gene annotation, and in a novel approach of gene co-expression network (GCN) clusters created with partial correlation and information theory (PCIT) as the prior information in GP models. The GCN clusters were nucleated with known genes for fibre biomechanics, i.e., fasciclin-like arabinogalactan proteins, and cluster size effects were evaluated. The most promising improvements in GP accuracy were achieved by using GCN clusters for cotton fibre elongation by 4.6%, and strength by 4.7%, where cluster sizes of two and three neighbours proved most effective. Furthermore, the improvements in GP were due to only a small number of SNPs, in the order of 30 per trait using the GCN cluster approach. Non-trait-specific biological time points, and genes, were found to have neutral effects, or even reduced GP accuracy for certain traits. As the GCN clusters were generated based on known genes for fibre biomechanics, additional candidate genes were identified for fibre elongation and strength. These results demonstrate that GCN clusters make a specific and unique contribution in improving the GP of cotton fibre traits. The findings also indicate that there is room for incorporating biology-based GCNs into GP models of genomic selection pipelines for cotton breeding to help improve precision breeding of target traits. The PCIT-GCN cluster approach may also hold potential application in other crops and trees for enhancing breeding of complex traits. [ABSTRACT FROM AUTHOR]

Nowadays, when regenerable alternative green sources are attracting more caution under sustainability targets, kapok and coconut fibers, known as natural fibers, have come to the fore as a very significant raw material source. In this experimental study, compressive strength, thermal insulation, and pore structure characteristics of kapok fiber (KP)– and coconut fiber (CC)–incorporated concrete samples under different curing conditions were analyzed. For that purpose, randomly distributed fiber-incorporated concrete mixtures containing 0%, 0.5%, 1%, and 1.5% KP and CC fiber by the weight of cement were prepared and under H2O2 and NaClO curing conditions, the effects of KP and CC fiber inclusion on properties mentioned above of fiber-incorporated concrete samples were researched in detail. Experimental results depict that a maximum thermal conductivity coefficient decrease of 24.31% was detected at a content ratio of 1.5% by the reason of the pore modification effect of used natural fibers in the H2O2 curing group. Because of the remarkable pore modification effect of KP fiber incorporation into the cement matrix compared to the CC fiber inclusion cases, strong linear correlations revealing the insulation-strength mechanism could be detected for both H2O2 and NaClO curing cases. This work intends to promote sustainable development in the building industry by integrating natural fibers into concrete mixtures as an innovative design approach. [ABSTRACT FROM AUTHOR]

A high-efficiency biosorbent based on the low-priced jute fiber was developed, characterized, and applied to remove the emerging organic contaminant diclofenac from aqueous solutions. Jute fiber was treated by NaOH (named AJF) followed by grafting different amounts of trimethyl[3-(trimethoxysilyl) propyl] ammonium chloride (named AJF-TTSAC). The composition, morphology, porosity, and adsorption features of the neat and modified jute fiber were evaluated and compared. The surface of neat JF was smooth, nonporous, and free of cracks. NaOH treatment increased the fibrillation, created cracks and grooves, and increased the oxygen content, total pore volume, and surface area. In comparison to AJF, grafting TTSAC filled in the crevices, grooves, and spaces between fibrillates, and decreased the total pore volume and surface area. The adsorption of diclofenac by the neat and modified JF occurred at highly acidic pHo and peaked at pHo 3. Among the neat and modified JF, AJF-TTSAC5 was the most efficient followed by AJF. The efficiency of AJF and AJF-TTSAC5 was highest using 1.00 g/L, at 35 °C and was not affected by the presence of NaCl. The Elovich, pseudo-first-order, and pseudo-second-order models described the adsorption kinetic satisfactorily with the marginal advantage of Elovich for AJF and pseudo-second-order for AJF-TTSAC5. The isotherm study exposed the multilayer and physisorption nature of the adsorption of diclofenac onto AJF and AJF-TTSAC5. The Langmuir monolayer saturation capacity of AJF-TTSAC5 was 37.43 mg/g which revealed its great potential relative to other adsorbents in the literature. The AJF and AJF-TTSAC5 were easily regenerated using distilled water and kept good performance for 5 repetitive cycles. [ABSTRACT FROM AUTHOR]

Natural lignocellulosic fibers (NLFs) have shown a great potential as reinforcements in composites in recent decades. Among other reasons, environmental concerns and the depletion of oil reserves justify research on natural composites as they offer an environmentally friendly alternative and align with the principles of sustainable development. Among the plethora of NLFs available in nature, the ubim fiber (Geonoma baculifera) has not yet been investigated as a reinforcement for composites in potential engineering applications. Therefore, this study evaluates, for the first time, the mechanical properties of epoxy composites with 10, 20, and 30 vol% of ubim fibers. These properties were assessed through Izod impact, tensile and flexural tests as well as dynamic mechanical analysis (DMA). The data were statistically analyzed using the ANOVA method. Scanning electron microscopy (SEM) analysis indicated a transition from a purely brittle fracture mechanism to a ductile-brittle combination as the fiber volume in the composite increased. Tensile tests of the composites demonstrated an increasing trend in strength and elastic modulus with fiber volume. The results of the flexural tests also displayed a similar trend in strength and elasticity modulus for the composites. The results of DMA tests showed that composite materials with a 30 vol% of ubim fibers exhibited a high glass transition temperature and a low tan δ value, suggesting higher stiffness of this composite compared to others. Overall, the results indicated that the incorporation of 30 vol% ubim fibers into the composites significantly improved their mechanical properties compared to other tested fiber fractions. Additionally, their functional characteristics, such as simplicity in the manufacturing process, low cost, and excellent strength-to-weight ratio, make these composites particularly suitable for applications in sectors such as the automotive industry, construction panels, and packaging. These factors contribute to the development of an efficient, sustainable, recyclable and environmentally friendly composite. [ABSTRACT FROM AUTHOR]

Due to increasing environmental concerns, there is growing interest in sustainable natural fiber-based hybrid composites. However, these materials face significant challenges across various fields and applications. This study aims to enhance jute-palmyra fiber-reinforced epoxy hybrid composites by incorporating nano-silica particles. The research investigates the improvement of physical, mechanical, and tribological characteristics of the composites with functionalized silica nanoparticle concentrations ranging from 0 % to 4 wt.%. Results show that increasing SiO2 content enhances the composite's density. Specifically, the composite with 3 wt.% SiO2 exhibits the highest flexural strength (71.20 MPa), while 2 wt.% SiO2 demonstrates superior tensile strength (55.52 MPa), impact resistance (4.02 J), and hardness (36 HV). Dry sliding wear tests using an L16 orthogonal array design reveal that hybrid nanocomposites with 2 wt.% SiO2 display superior wear resistance under specified conditions. These findings underscore the significant performance advantages of SiO2-natural fiber hybrid composites, highlighting their potential in sustainable material applications. [ABSTRACT FROM AUTHOR]

The increasing demand for sustainable materials in high-value applications, particularly in the automotive industry, has prompted the development of biocomposites based on renewable or recyclable matrices and natural fibers as reinforcements. In this context, this paper aimed to produce composites with improved mechanical and thermal properties (tensile, flexural, and heat deflection temperature) through an optimized process pathway using a biobased polyamide reinforced with short basalt fibers. This study emphasizes the critical impact of fiber length, matrix adhesion, and the variation in matrix properties with increasing fiber content. These factors influence the properties of short-fiber composites produced via primary processing using extrusion and shaped through injection molding. The aim of this work was to optimize extrusion conditions using a 1D simulation software to minimize excessive fiber fragmentation during the extrusion process. The predictive model's capacity to forecast fiber degradation and the extent of additional fiber breakage during extrusion was evaluated. Furthermore, the impact of injection molding on these conditions was investigated. Moreover, a comprehensive thermomechanical characterization of the composites, comprising 10%, 20%, and 30% fiber content, was carried out, focusing on the correlation with morphology and processing using SEM and micro-CT analyses. In particular, how the extrusion process parameters adopted can influence fiber breakage and how injection molding can influence the fiber orientation were investigated, highlighting their influence in determining the final mechanical properties of short fiber composites. By optimizing the process parameters, an increment with respect to bio-PA11 in the tensile strength of 38%, stiffness of 140%, and HDT of 77% compared to the matrix were obtained. [ABSTRACT FROM AUTHOR]

The introduction of bio-based matrices in automotive applications would, in principle, increase their sustainability and, in case the use of secondary raw materials is also involved, even result in reduced resource depletion. The bio-based polymer composite matrix that has been mainly brought forward towards industrial application is poly(lactic acid) (PLA), which has often been proposed as the replacement for matrices based on polyolefins in fields such as packaging and short-term commodities since, in general, it matches the needs for conventional thermoplastic production processes. The passage to the automotive sector is not obvious, though: problems affecting durability, the relation with water and the environment, together with the requirement for outstanding mechanical and impact performance appear very stringent. On the other hand, PLA has obtained durable success in additive manufacturing as a competitor for acrylonitrile butadiene styrene (ABS). Also, the perspective for 3D and 4D printing does not appear to be confined to bare prototyping. These contrasting pieces of evidence indicate the necessity to provide more insight into the possible development of PLA use in the automotive industry, also considering the pressure for the combined use of more sustainable reinforcement types in automotive composites, such as natural fibers. [ABSTRACT FROM AUTHOR]

Cricula trifenestrata Helfer (commonly known as Amphutukoni muga/Cricula silkworm), a wild sericigenous insect produces golden yellow silk similar to Antheraea assamensis (muga silkworm), with significant potential as a natural fiber and biomaterial. Cricula is considered as a pest as it competes for food with muga, which produces the prized golden silk. This study focuses on decoding the mitochondrial genome of C. trifenestrata using next-generation sequencing technology and includes comparative analysis with Bombycoids and other lepidopteran insects. We found that the Cricula mitogenome spans 15 425 bp and exhibits typical gene content and arrangement consistent with other Saturniids and lepidopterans. All protein-coding genes were found to undergo purifying selection, with the highest and lowest conservation observed in the cox1 and atp8 gene, respectively, indicating their potential role in future evolutionary events. We identified two types of mismatches: 23 "G–U" and 6 "U–U" pairs, similar to those found in Actias selene among the Saturniids. Additionally, our study uncovered the presence of two 33 bp repeat units and a "TTAGA" motif in the control region, in contrast to the typical "ATAGA" motif, suggesting functional similarity with evolving sequences. Furthermore, phylogenetic analysis supports the close relationship of Cricula with other species within the Saturniidae family. [ABSTRACT FROM AUTHOR]

[Display omitted] • Genome-wide mining of QTLs of fiber yield and fiber quality traits were beneficial to better understanding their genome level distributions. • A total of 64 stable QTLs of fiber yield and 75 stable QTLs of fiber quality were identified, which formed 33 clusters, indicating that the correlations between fiber yield and quality traits have complex genetic components. • These QTLs formed expression network, via their candidate genes, to orchestrate fiber development and the formation fiber yield and quality. • The candidate gene, GH_D07G2262, an upland cotton cellulose synthase 4 (GhCesA 4) gene had pleiotropic functions during cotton fiber development, which positively regulates fiber length and strength, and negatively lint percentage. Upland cotton is an important allotetrapolyploid crop providing natural fibers for textile industry. Under the present high-level breeding and production conditions, further simultaneous improvement of fiber quality and yield is facing unprecedented challenges due to their complex negative correlations. The study was to adequately identify quantitative trait loci (QTLs) and dissect how they orchestrate the formation of fiber quality and yield. A high-density genetic map (HDGM) based on an intraspecific recombinant inbred line (RIL) population consisting of 231 individuals was used to identify QTLs and QTL clusters of fiber quality and yield traits. The weighted gene correlation network analysis (WGCNA) package in R software was utilized to identify WGCNA network and hub genes related to fiber development. Gene functions were verified via virus-induced gene silencing (VIGS) and clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 strategies. An HDGM consisting of 8045 markers was constructed spanning 4943.01 cM of cotton genome. A total of 295 QTLs were identified based on multi-environmental phenotypes. Among 139 stable QTLs, including 35 newly identified ones, seventy five were of fiber quality and 64 yield traits. A total of 33 QTL clusters harboring 74 QTLs were identified. Eleven candidate hub genes were identified via WGCNA using genes in all stable QTLs and QTL clusters. The relative expression profiles of these hub genes revealed their correlations with fiber development. VIGS and CRISPR/Cas9 edition revealed that the hub gene cellulose synthase 4 (GhCesA4 , GH_D07G2262) positively regulate fiber length and fiber strength formation and negatively lint percentage. Multiple analyses demonstrate that the hub genes harbored in the QTLs orchestrate the fiber development. The hub gene GhCesA4 has opposite pleiotropic effects in regulating trait formation of fiber quality and yield. The results facilitate understanding the genetic basis of negative correlation between cotton fiber quality and yield. [ABSTRACT FROM AUTHOR]

This study delves into the realm of M70, high-performance concrete (HPC) with a focus on enhancing its mechanical and sustainable properties through the incorporation of nanomaterials, specifically nanosilica, and organic composites derived from abaca fibers. HPC is pivotal in contemporary construction for its superior durability, strength, and resistance to environmental factors. The integration of nanosilica aims to refine the microstructure of the concrete at the nanoscale, enhancing its strength and durability. Simultaneously, the introduction of organic composites from abaca fibers seeks to impart eco-friendly characteristics to the concrete mix, addressing sustainability concerns. The research methodology involves systematically varying the proportions of nanosilica (0%, 0.5%, 1.0%, 1.5%) as a partial replacement for cement in the concrete and additionally, abaca fibers (0%, 0.25% and 0.5%) were used to enrich the durability. Mechanical testing will be conducted to assess the impact of these additives on the concrete's structural performance, while durability testing will focus on resistance to environmental factors such as moisture and chemical exposure. The outcomes of this study enriching the concrete performance and optimization of high-performance concrete (1% of nanosilica and 0.25% of abaca fiber) is the superior quality compared to all other mixes. [ABSTRACT FROM AUTHOR]

In the present work, sugarcane bagasse (SCB) fibers were used as natural reinforcement to low-density polyethylene matrix to benefit from and get rid of unexploited Egyptian natural resources in bio-composites applications. The samples were prepared by injection molding processes using various fiber content (10 wt%, 20 wt% and 30 wt%). The fibers were treated chemically with 3% sodium hydroxide (NaOH) to improve compatibility and adhesion with the matrix. Maleic anhydride was added as a coupling agent to improve interfacial adhesion. The mechanical properties such as tensile and flexural tests were performed according to ASTM standards. The chemical resistance of fabricated composites was also examined. The results indicated that the alkali treatment modified the fiber surface and increased the interaction between the fiber and the matrix. They also showed that adding the coupling agent improved the interfacial adhesion between the fibers and the polyethylene. Additionally, the results showed that the maximum improvement of the fabricated composites with various fiber loadings was found at the 30 wt% treated coupled composites with tensile strength (17.5 MPa) and flexural (19.6 MPa). This reflected an enhancement in tensile strength by 41% and flexural strength by 72% at 30 wt% fiber compared to the neat polymer, respectively. The results also indicated that chemical resistance decreased with increasing fiber content. But it was found that the chemical resistance for aqueous solution 3.5 wt% Nacl was enhanced when the coupling agent was used. The greatest improvement in the resistance was observed for coupled treated SCB composite, followed by coupled untreated SCB composites. This reflected that the addition of maleic anhydride (MAPE) along with the composites improved the chemical resistance of the composites for aqueous solution 3.5 wt% Nacl. [ABSTRACT FROM AUTHOR]

This paper presents a comparative study on the effect of two local Libyan grasses, Stipa tenacissima (locally known as Halfa) and Retama raetam (locally known as R'tem) on the mechanical properties of styrene-butadiene rubber composites (SBR). For this purpose, the effect of filler type and content (10, 20, 30 and 40 wt%) on the mechanical properties of the composites including stress at break, elongation at break, impact strength and microhardness were evaluated. The stress at break of SBR increased only with the addition of 20 wt% and 30 wt% of Halfa. The highest value of stress at break was obtained by composites made with 20 wt% Halfa content. The elongation at break was significantly decreased with the addition of Halfa and R'tem. Generally, the elongation at break of the composites made with R'tem was slightly higher than that of composites made with Halfa. On the other hand, the addition of Halfa resulted in composites with relatively higher impact properties. The impact strength of these composites was increased with increasing the Halfa content up to 30 wt% after which it was decreased noticeably. However, the impact strength of composites made with R'tem did not follow a clear path with increasing R'tem content. Furthermore, the incorporation of Halfa and R'tem resulted in a significant increase in the hardness properties of the composites. R'tem showed to produce composites with higher hardness compared to those made with Halfa. Composites made with Halfa possess better toughness and ductility to a certain degree in comparison to composites made with R'tem. Although, Halfa appears to be relatively better than R'tem in reinforcing SBR, both fillers appeared to be good candidate filler to produce low cost and density polymer composites with acceptable mechanical properties. [ABSTRACT FROM AUTHOR]

This study offers a detailed examination of vinyl ester composites strengthened with nettle fibres and annealed biosilica from foxtail millet husk biomass waste. The primary objective is to investigate how the different dwell time processed heat treated biosilica particles perform under repeated and prolonged loading applications in natural fibre-reinforced polymer composite materials. The biosilica particles were annealed at 1200 °C and dwelled for 2 h and 4 h. The results highlight VNS32 (resin with nettle fibre of 30 vol.% and biosilica of 2 vol.%) as the superior composite, exhibiting higher fatigue counts of 29,108, 27,898, and 26,247 for 25%, 50%, and 75% of the ultimate tensile strength (UTS). Similarly, VNS32 demonstrates superior values in creep and dynamic mechanical analysis (DMA). In creep testing, VNS32 shows creep strain values of 0.0015, 0.0019, and 0.0035 for 5000 s, 10,000 s, and 15,000 s, while in DMA, it achieves a storage modulus of 5.6 GPa at 107 °C and a loss factor of 0.42. These findings suggest that the utilization of prolonged annealed biosilica contributes to enhanced structural integrity and uniform load transfer, both in normal and cyclic loading conditions at specific temperatures. Moreover, these composites could be used in automotives, lightweight building material applications, drones, defence and food packaging where lightweight and high strength is required. [ABSTRACT FROM AUTHOR]

Natural fibre-reinforced hybrid polymer composites have gained significant attention worldwide in mechanical, aerospace, and automotive applications. Advanced machining techniques, such as abrasive water jet machining, have emerged as a solution to various challenges in this field, offering benefits such as the ability to shape complex geometries, achieve superior performance, improve surface characteristics, and attain high levels of accuracy. The research proposes a new approach for producing biodegradable hybrid composites composed of polylactic acid, bamboo particles, and montmorillonite clay using an innovative solvent-free stir-casting technique optimised for maximum efficiency. To systematically analyse the surface roughness, kerf angle, and material removal rate, a Box–Behnken design of experiments was employed, with the traverse rate, abrasive feed rate, and stand-off distance considered design variables. Analysis of variance was used to determine the significance of the differences between means of variables, while response surface methodology was utilised to establish the explicit relationship between the design variables and the response of the composite machining. The particle swarm optimisation algorithm was also employed to determine the optimal values of the design parameters for machining composites. The results showed that the traverse rate was the most influential factor, followed by the abrasive feed rate. In contrast, the stand-off distance had a relatively lower level of influence. The optimal process parameters were identified, resulting in a minimum surface roughness of 5.56 μm, a kerf taper of 0.0044 radians, and a material removal rate of 1175 g/min. [ABSTRACT FROM AUTHOR]

The use of nano-fillers as reinforcement in natural fibers-based hybrid composites has gained prominence in multiple sectors in recent years because of their virtuous mechanical and physical characteristics. The impeccable properties of nano-fillers like their high aspect ratio and larger surface area have made them to be used in areas for instance, sectors like aviation, automotive, and biotechnology fields. This study focuses on examining how various weight percentages of nano-calcium carbonate (NCaCO3) fillers (2%, 5%, 7%) impact the elastic properties of innovative hybrid composites blended with banana and kenaf fibers, combined with epoxy. The elastic characteristics of the suggested composite, including longitudinal elastic modulus (LEM), transverse elastic modulus (TEM), longitudinal Poisson's ratio (LPR), and longitudinal shear modulus (LSM), are analyzed through micromechanical models such as the Mori–Tanaka (M–TA) model, generalized self-consistent (GS-C) model, and modified Halpin–Tsai (M-HT) model. The composite consisting of a solitary banana fiber sheet, a solitary NCaCO3 mix epoxy sheet, and another solitary kenaf fiber sheet is modeled in ANSYS APDL simulation software. The composite's layers are organized in a specific order: starting with banana fiber at 90° orientations, followed by a layer of NCaCO3 and epoxy at 0° orientations, and concluding with kenaf fiber at 90° orientations. The ANSYS software is employed to analyze the total sum deformation and strength of the suggested composite. The outcomes obtained from this research are contrasted and confirmed through comparison with existing literature. The inclusion of 7 wt% of NCaCO3 in the suggested hybrid composite is found to have the highest elasticity and ductility in comparison with 2 wt% and 5 wt% of NCaCO3. The composite containing 7 wt% NCaCO3 demonstrates the greatest load-bearing capability. Additionally, while calculating the elastic characteristics of the proposed composite, both the modified Halpin–Tsai (M-HT) model and the generalized self-consistent model (GS-C) outperform the Mori–Tanaka model (M–TA). Furthermore, the hybrid impact is computed for the suggested composite to analyze the tensile strain rates at which failure occurs for banana and kenaf fibers within the composite hybrid structure. The computed hybrid value of 0.5 indicates that the failure rate of a non-hybridized composite is 50% more than the hybridized composite. This signifies that the hybrid composites have high load-bearing strength, high elasticity, and stiffness. [ABSTRACT FROM AUTHOR]

Featured Application: Building materials for products with lower carbon footprints and increased mechanical properties. This article's aim is to analyze physical, mechanical, and fracture properties as well as the thermal investigation of geopolymer composites reinforced with flax, glass fiber, and also the hybrid combination of fibers. Two types of matrices were considered as composites matrices. The first composition was based on fly ash and river sand. The second matrix composition contained fly ash and glass spheres. The content of reinforcement was 1% by mass. Compressive strength and three-point bending fracture tests were performed. The values of fracture toughness and fracture energy were determined. The resonance method was used to verify the dynamic characteristics, such as the dynamic modulus of elasticity and the dynamic Poisson ratio. The results show that single-type fibers in composites based on fly ash and glass spheres did not affect compressive strength. However, introducing hybrid reinforcement increased compressive strength by about 10% compared to the reference specimens. Flax fibers and hybrid reinforcement ensured higher fracture toughness and energy. The results also revealed great potential for glass sphere application to geopolymer materials in terms of fracture mechanics and thermal properties. Despite the lower strength properties in relation to geopolymers based on sand aggregate, applying reinforced fibers into the composite with glass spheres enhanced the compressive strength compared to other materials. Materials modified with glass spheres have a thermal conductivity twice as low as that of materials containing river sand. [ABSTRACT FROM AUTHOR]

Hybrid composites made of natural fibers are replacing composites made of synthetic fibers, which is better for the environment. In this study, a Cotton/Corn Hybrid Composite was prepared using compression moulding and evaluated the Abrasive Water Jet Machining (AWJM) process variables on surface quality. The AWJM investigations were conducted using experimental design approaches, with variables including water pressure, nozzle transfer speed, and standoff distance. Among these variables, it was determined that nozzle transfer speed had the most influential impact on surface quality. The optimal machining parameters P2, s1, and d1 were identified, resulting in a surface roughness of 4.459 μm. This demonstrates that accomplishing better surface quality is attainable through the suitable parameter selection. Further, the prediction model's efficiency was validated by establishing a strong relationship between the experimental, predicted, and validated surface roughness values. This highlights the model's reliability in predicting and optimizing surface quality in the AWJM process. [ABSTRACT FROM AUTHOR]

Fiber‐reinforced composites have emerged as versatile materials with applications spanning diverse industries, driven by their exceptional mechanical properties and lightweight nature. This review provides a comprehensive overview of natural fiber‐reinforced composites, focusing on their enhanced mechanical and functional properties achieved through modern processing techniques. The study delves into various manufacturing methods, such as thermoforming, additive manufacturing, compression molding, electro‐spinning, pultrusion and autoclave molding, which have significantly contributed to the advancement of these composites. The review further investigates the multifaceted properties of these composites, which highlights the versatility and applicability of these materials and provides a holistic understanding of their potential applications. Additionally, the work addresses current research gaps and identifies prospects, shedding light on the evolving landscape of natural fiber‐reinforced composites. The synthesis of processing techniques, material properties and potential applications offers valuable insights for researchers, practitioners and industries aiming to harness the full potential of these sustainable and high‐performance materials. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Natural plant fibers are hierarchical structures with multi-level microstructures. With advances in composite material science, these fibers have been widely used in various polymer products. Therefore, it is crucial to quantitatively understand the relationship between their microstructures and mechanical behavior. This paper utilizes the Mori-Tanaka micromechanics model, viscoelasticity theory, and Zakian's inversion method to study the impact of plant fiber microstructure on the viscoelastic behavior of multiscale structures. At the microscopic scale, the macromolecular polymer (matrix) and cellulose (fiber) are first homogenized. The second homogenization involves the cell wall microstructure, and the third homogenization considers the porosity of the cell wall and lumen to predict the effective modulus of fiber bundles. By applying the principle of elasticviscoelastic correspondence, the viscoelastic mechanical parameters of plant fibers are calculated. The study examines the effects of cellulose crystallinity and lumen porosity on the structural stiffness and viscoelastic properties of fibers, identifying these factors as key influences on the mechanical behavior of plant fibers. Given their significant economic potential, the feasibility of using tobacco plant fibers as bio-based materials is also explored. [ABSTRACT FROM AUTHOR]

The use of nano-fillers as reinforcement in natural fibers-based hybrid composites has gained prominence in multiple sectors in recent years because of their virtuous mechanical and physical characteristics. The impeccable properties of nano-fillers like their high aspect ratio and larger surface area have made them to be used in areas for instance, sectors like aviation, automotive, and biotechnology fields. This study focuses on examining how various weight percentages of nano-calcium carbonate (NCaCO3) fillers (2%, 5%, 7%) impact the elastic properties of innovative hybrid composites blended with banana and kenaf fibers, combined with epoxy. The elastic characteristics of the suggested composite, including longitudinal elastic modulus (LEM), transverse elastic modulus (TEM), longitudinal Poisson's ratio (LPR), and longitudinal shear modulus (LSM), are analyzed through micromechanical models such as the Mori–Tanaka (M–TA) model, generalized self-consistent (GS-C) model, and modified Halpin–Tsai (M-HT) model. The composite consisting of a solitary banana fiber sheet, a solitary NCaCO3 mix epoxy sheet, and another solitary kenaf fiber sheet is modeled in ANSYS APDL simulation software. The composite's layers are organized in a specific order: starting with banana fiber at 90° orientations, followed by a layer of NCaCO3 and epoxy at 0° orientations, and concluding with kenaf fiber at 90° orientations. The ANSYS software is employed to analyze the total sum deformation and strength of the suggested composite. The outcomes obtained from this research are contrasted and confirmed through comparison with existing literature. The inclusion of 7 wt% of NCaCO3 in the suggested hybrid composite is found to have the highest elasticity and ductility in comparison with 2 wt% and 5 wt% of NCaCO3. The composite containing 7 wt% NCaCO3 demonstrates the greatest load-bearing capability. Additionally, while calculating the elastic characteristics of the proposed composite, both the modified Halpin–Tsai (M-HT) model and the generalized self-consistent model (GS-C) outperform the Mori–Tanaka model (M–TA). Furthermore, the hybrid impact is computed for the suggested composite to analyze the tensile strain rates at which failure occurs for banana and kenaf fibers within the composite hybrid structure. The computed hybrid value of 0.5 indicates that the failure rate of a non-hybridized composite is 50% more than the hybridized composite. This signifies that the hybrid composites have high load-bearing strength, high elasticity, and stiffness. [ABSTRACT FROM AUTHOR]

Purpose: The paper aims to investigate the dynamic measurement of the water vapour resistance. The water vapour diffusion kinetics depends on the fibre's material. So, water vapour resistance measurement times till the equilibrium steady state can vary in the case of natural fibres compared to synthetic fibres. Devices for determining water vapour resistance according to the ISO 11092 standard allow static values to be measured. Design/methodology/approach: In this study to investigate the dynamic of the water vapour resistance, a new parameter named "holding period" was introduced and defined as the time from sample placement on the measuring head until the measuring process begins. The holding period was varied as 0, 30, 60, 90, 120, 180, 240 and 300 s. Wool and cotton knitted fabrics were tested as natural fibres and compared to 100% polyester and 90% polyester/10% elastane as synthetic fibres. Measurements were conducted under both air velocities of 1 and 2 m/s. The experimental test data were statistically analysed based on ANOVA and four-in-one residual plots. Findings: Statistical analysis of experimental tests shows that the holding period affects water vapour resistance in both air velocities of 1 and 2 m/s and on the measured values in the case of hydrophilic fibres. Research limitations/implications: The study of the dynamic relative water vapour permeability of natural and synthetic is an important area of interest for future research. Practical implications: It is recommended to hold the samples on the top of the head measurement before starting the test. Originality/value: Following the ISO 11092 standard, the static values of the water vapour resistance were measured without considering the dynamic behaviour of the water vapour diffusion through the textile fabrics. This paper fulfils an experimental dynamic measurement of the water vapour resistance. [ABSTRACT FROM AUTHOR]

The automotive industry is under significant pressure to curb greenhouse gas emissions from their products as the negative impacts on the environment are increasingly apparent. As such, there is significant interest within the industry to develop low-carbon footprint materials. Natural fiber composites are therefore appealing due to both their decreased carbon footprint, as well as their relatively low cost, low density, and beneficial acoustic properties. This research specifically focuses on the use of paper fibers as composite reinforcements. Paper offers additional benefits over other natural fiber types in that it is globally available, does not compete with food resources, and has well-established quality control techniques. The goal of this work was to study the manufacturing of polypropylene (PP)-paper fiber composites using a hybrid wet-lay/compression molding processing. The processing parameters studied included molding temperature, molding duration, and molding pressure. Paper composites were characterized for properties including flexural strength, impact strength, and water uptake rate. An optimal set of processing parameters was identified in which cycle time and energy inputs (e.g. temperature and pressure) were minimized while retaining desired material properties. [ABSTRACT FROM AUTHOR]

Highlights Continuous plant yarn‐reinforced polylactic acid (PLA) composites were produced through in situ 3D printing, focusing on how plant fiber attributes influence the crystallization, mechanical, and rheological properties of the printed composites. The aim of this study was to assess the viability of plant fibers as substitutes for synthetic ones in engineering additive manufacturing. Plant fibers promoted the crystallization of PLA due to their shear induction and nucleation agent induction effects. The inherent triangular void defect during printing decreased with increasing plant fiber‐volume fraction. Rheological analysis revealed a transition to more elastic behavior post‐fiber addition, indicating solid‐like properties. The tensile strength of flax fiber‐yarn/PLA composite (volume fraction of 50.79%) was 342.37% higher than that of pure PLA, with a 22.2% lower density than pure PLA. Flax fiber demonstrated a superior reinforcement effect than carbon fiber in compressive strength for 3D printed honeycomb sheets with lower energy consumption and footprint. Optimizing fiber characteristics holds promise for high‐performance 3D‐printed natural fiber composites, particularly in vehicle applications. Plant fiber/polylactic acid (PLA) composites were in situ printed with a volume fraction of 50.79%. Plant fibers promoted the crystallization of PLA during the printing process. The tensile strength of flax fiber/PLA increased by 342.3% with a 22.2% lower density than PLA. Flax fiber showed a better reinforcement than carbon fiber in a compressive test of printed honeycomb. [ABSTRACT FROM AUTHOR]

Highlights In this study, a comparative analysis of the use of recycled PET (R‐PET) in synthetic and natural fiber blended composites was made. PET, R‐PET, and PP yarns were folded with reinforcing fibers by commingling technique and then fabrics were prepared using weaving technology. Hot compression molding technology was used for composite fabrication. Tensile and impact characterization revealed the significant influence of reinforcing and TP fibers on mechanical properties. R‐PET matrix glass fiber reinforced composites exhibited 41.77% higher tensile strength than virgin PET and 20.41% higher than PP. In terms of tensile strength for linen reinforced samples, R‐PET shows an impressive 181% improvement over virgin PET and 154% over PP. According to the drop weight test results, glass fiber reinforced R‐PET matrix sample exhibited a peak load value 53% higher than that of the virgin PET matrix, although it was 9.47% lower than the PP matrix. In linen fiber reinforced samples, R‐PET demonstrated a 57.73% improvement over virgin PET but lower by 9.47% compared to the PP matrix. During this time, DSC, TGA, FTIR, and flammability tests were also performed on the composite samples. The results showed that R‐PET has easy processability as a matrix material and provides better wetting of the reinforcing fibers. For this reason, it has been shown that R‐PET matrix samples provide better mechanical properties than both PET and PP matrix samples. It has also been determined that R‐PET is a more suitable matrix material compared with natural fiber reinforced composites. Commingled yarns were used for preparing composites. R‐PET yarns were used as matrix in preparing glass and linen reinforced composites. R‐PET was compared with virgin PET and PP yarns. R‐PET showed great potential in easy preparation of TP composites. Composites made with R‐PET showed improved thermal and mechanical properties. [ABSTRACT FROM AUTHOR]

AbstractIn this work, an attempt is made to produce a ductile construction system using natural fiber-based engineered cementitious composite (ECC) beams where the conventional longitudinal steel reinforcements are replaced using glass fiber-reinforced polymer (GFRP) bars. In total, sixteen medium-scale reinforced ECC beams were tested under an un-symmetric three-point bending configuration to generate shear failure. The parameters considered as a part of the experimental program include (a) type of longitudinal reinforcement (steel or GFRP) and (b) type of natural fiber (flax, hemp, kenaf and pineapple). In addition, a detailed analytical study was performed using the Architectural Institute of Japan (AIJ) method, and a modified equation was proposed for predicting the shear behavior of FRP reinforcement using ECC beams. Test results reveal that the use of GFRP reinforcements resulted in the reduction of peak load from 33.6% to 65.4% when compared to similar steel-reinforced R-ECC beams. However, the failure mode was highly ductile due to the excellent fiber bridging mechanism, multi-crack formation and effective stress redistribution at the crack tip. The predictions obtained from the modified AIJ method improved the accuracy of shear capacity FRP-reinforced ECC sections when compared to the experiments. [ABSTRACT FROM AUTHOR]

Translation abstract Investigating natural rubber latex (NRL) composites through compressive testing for renewable and sustainable building materialsThis article explores the innovative use of natural rubber latex (NRL) as a fundamental component in the development of sustainable and renewable composite building materials, particularly focusing on incorporating wood chips as reinforcing particles. The study investigates the compressive mechanical properties of various composite formulations, analysing the influence of NRL contents and particle types – considering different wood species, shapes and sizes. Key factors such as particle geometry, NRL content, and sample preparation methods are identified as crucial factors in enhancing the mechanical properties of these composites. The results show that NRL composites exhibit distinctive characteristics like non‐linear behaviour, hysteresis, stress relaxation, and the Mullins effect during compression tests. The significance of these composite materials in construction is heightened by their potential to utilize NRL sourced from plants other than rubber trees, such as dandelions, thus advancing sustainable construction practices. This research aims to focus attention on exploring new, flexible, and highly customized composite materials by utilizing natural fibres and NRL across a range of construction applications. [ABSTRACT FROM AUTHOR]

Research on the sustainable production of building materials has been increasing from time to time. The construction industry is one of the sectors that leads to the depletion of significant amounts of nonrenewable resources, such as minerals. The ecosystem is deteriorated, and carbon dioxide (CO2) emissions are enormous in the environment due to the use of fossil fuel-based materials. The purpose of this paper is to review the use of plant fibers (hereafter NF) for reinforcement in cementitious concrete. Concrete, plant fibers, their chemical nature, and characteristics are highlighted in an overview. The most important issues in NF-concrete compatibility were discussed, which could provide research opportunities. Modification of NFs and the cement matrix are examined as methods for improving compatibility and degradation. Moreover, the properties and longevity of cementitious materials that are reinforced with natural fibers are also examined. Finally, the review emphasizes the significant research gaps and future research prospects identified in the reviewed papers. [ABSTRACT FROM AUTHOR]