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The growing awareness of socioeconomic and environmental issues and the high percentage of petroleum resources consumed and new environmental regulations have fueled efforts to develop innovative, cutting-edge, environmentally friendly materials with a wide range of applications. Due to environmental and sustainability concerns, the advancement of biocomposites has resulted in tremendous breakthroughs in green materials in this century. Their primary goal is to replace current synthetic petroleum-based composites with natural resources. Materials derived from nonrenewable petroleum-based sources are hazardous and expensive to produce; on the other hand, biocomposites derived from natural sources are biodegradable, recyclable, non-abrasive, and compostable and have properties comparable to synthetic fiber composites. Natural fibers are low-cost, lightweight, biodegradable, renewable, and environmentally friendly alternatives to synthetic fibers like glass and carbon fiber. The long-term viability of natural fiber-based composite materials has led to increased use in various production industries. However, the manufacturing process of natural fiber-based biocomposites is still plagued by some difficulties, such as poor adhesive propensity, moisture absorption, poor fire resistance, low impact strength, and low durability. This review provides a panoramic view to provide insight into different aspects of biocomposites based on natural fibers and polymers in terms of properties and applications, which will pave the way for future biocomposites research in academic and commercial contexts. [ABSTRACT FROM AUTHOR]

With growing restrictions on the exploitation and trade of current stringed musical instruments fingerboard materials such as ebony and rosewood, for economical and ethical reasons, instrument makers are looking for alternative materials. The present work describes the development of a homogeneous 60% bio-based flax fibre composite material with physical properties similar to commonly used fingerboard woods. As a proof of concept, prototype guitar neck was built using the material, demonstrating its compatibility with existing guitar manufacturing techniques. [ABSTRACT FROM AUTHOR]

• This study focuses on composites, namely natural composites. • This natural composite comprises 40 to 50 wt% of rice straw fiber, neem saw dust fiber and hybrid composites. • A review of several RSNWP hybridization and chemical treatment techniques. • Morphology and mechanical properties of several materials tests were discussed. • Emerging applications of RSNWPs are also examined while keeping environmental sustainability in mind. Recent years have seen an increase in the use of natural fibers. Rice straw/natural fiber hybrid composites can recycle agricultural waste easily and eliminate fine silica ash pollution. Composite specimens are created by hand lay-up as per ASTM standards. Unsaturated polyester resins and rice straws are studied using scanning electron microscopy. Hybrid composites reinforced with rice straw and neem powder perform better. The optimal fiber content for impact and flexural strength is 50 % by volume fraction. RSNWP6 fibers with hybrid properties have more significant impact strength, hardness, and flexural strength than other fibers at 516.86 J/m, 45 BIU, and 80.03 MPa. [ABSTRACT FROM AUTHOR]

The purpose of this study is to evaluate in detail the usability of new cellulosic fibers extracted from the stem of the plant Strelitzia reginae, as a potential reinforcement for polymer composites. The morphological, physical, thermal, and mechanical properties of fibers were addressed for the first time in this paper. Both untreated and alkali-treated fibers were characterized, using scanning electron microscopy (SEM), Fourier-transform infrared, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), optical microscope, and X-ray diffraction (XRD) and applying tensile test for determining the mechanical behavior. For both fiber treated at one hour (T1H) and at four hours (T4H), the stem anatomy and fiber SEM micrographs showed a strong presence of fiber cells. Thermogravimetry and DSC showed that the fiber was thermally stable up to 233°C for untreated fiber, 254 and 240°C, respectively, In single-fiber tensile tests, it was observed that the fibers extracted from the stem of Strelitzia reginae were strong. The mean values of Young's modulus exhibited by untreated fibers and treated (T1H) and (T4H) are, respectively, 9.89 GPa, 12.08, and 18.39 GPa. Also mean values of tensile strength are 271.79, 306.23, and 421.39 MPa. The XRD reveals the presence of cellulose with a Crystallinity Index of 70% for raw fiber and 72% for the treated one. Fourier-transform infrared analysis well demonstrated the effect of chemical treatment. It can be concluded from the results of all above experiments that the Strelitzia reginae fibers (SR) could serve as a possible reinforcement in composite materials. [ABSTRACT FROM AUTHOR]

Mainly used for the paper industry, hemp fibres present a high potential for valorisation in new industrial of semi-structural or structural composites material applications. To reach certain markets, it is inevitable to certify their behaviour and durability in humid environment which is currently lacking in the literature. This article provides a better insight into the moisture sorption, on a wide range of relative humidity (HR), from 9 % to 98 %, and its effect on the evolution of the tensile behaviour and performances of hemp/epoxy unidirectional biocomposites. Tensile behaviour is significantly modified by moisture content with non-linear behaviour becoming more evidenced. Increase of moisture leads to an exponential decay of tensile modulus but a non-monotonic evolution through an optimum of tensile stress and strain at break. Complex compressive hygroscopic stress state at the fibre/matrix interface is hypothesised so that load transfer is kept until a moisture content threshold is reached and moisture induced degradation triggered. [ABSTRACT FROM AUTHOR]

Composite reinforcement is defined as a technique to improve the engineering characteristics of composite and a fiber reinforced composite (FRC) is a composite material consisting of a polymer matrix imbedded with high-strength fibers, synthetic fibers or natural fibers. Natural fibers have recently become attractive to researchers, engineers, and scientists as an alternative reinforcement for FRCs. Nanocomposite shows considerable applications in different fields because of larger surface area, and greater aspect ratio, with fascinating properties. Being environmentally friendly, applications of nanocomposites offer new technology and business opportunities for several sectors, such as aerospace, automotive, electronics, and biotechnology industries. Hybrid bio-based composites that exploit the synergy between natural fibers in a nanoreinforced bio-based polymer can lead to improved properties along with maintaining environmental appeal. This review article intended to investigate natural fiber/nanofiller-based hybrid composite with specific concern to their physical and mechanical properties. [ABSTRACT FROM AUTHOR]

Environmental awareness of the global waste problem has driven the development of new green composites made from either renewable or biodegradable materials. Among the variety of available green composites, natural composites based on poly-lactic acid (PLA) have shown noteworthy performance due to their short degradation time after disposal, good strength, and ease of processing by conventional methods. In particular, green composites manufactured with PLA matrix reinforced with Manicaria Saccifera fabric (MF) display mechanical properties that have shown to be very competitive compared with similar materials. In this study, the tensile properties of a green composite of PLA reinforced with MF are optimized by using a Taguchi method approach. The processing parameters, fabric chemical treatment parameters, compression molding parameters, and fiber content are analyzed simultaneously to yield the optimum biocomposite properties. The predicted optimum parameters are experimentally verified. Tensile tests and scanning electron microscope (SEM) analysis are used. Significant improvements on both the tensile strength (114.2%), and the elastic modulus (120.6%) of the biocomposite are achieved. [ABSTRACT FROM AUTHOR]

One of the big global, environmental, and socioeconomic challenges of today is to make a transition from fossil fuels to biomass as a sustainable supply of renewable raw materials for industry. Growing public awareness of the negative environmental effects of petrochemical-based products adds to the need for alternative production chains, especially in materials science. One option lies in the value-added upcycling of agricultural byproducts, which are increasingly being used for biocomposite materials in transport and building sector applications. Here, sunflower by-product (obtained by grinding the stems) is considered as a source of natural fibers for engineered biocomposite material. Recent results are shown for the main mechanical properties of sunflower-based biocomposites and the socioeconomic impact of their use. This paper demonstrates that sunflower stem makes a good candidate feedstock for material applications. This is due not only to its physical and chemical properties, but also to its socioeconomic and environmental rationales. [ABSTRACT FROM AUTHOR]

Natural fibers today are a popular choice for applications in composite manufacturing. Based on the sustainability benefits, biofibers such as plant fibers are replacing synthetic fibers in composites. These fibers are used to manufacture several biocomposites. The chemical composition and properties of each of the fibers changes, which demands the detailed comparison of these fibers. The reinforcement potential of natural fibers and their properties have been described in numerous papers. Today, high performance biocomposites are produced from several years of research. Plant fibers, particularly bast and leaf, find applications in automotive industries. While most of the other fibers are explored in lab scales they have not yet found large-scale commercial applications. It is necessary to also consider other fibers such as ones made from seed (coir) and animals (chicken feather) as they are secondary or made from waste products. Few plant fibers such as bast fibers are often reviewed briefly but other plant and animal fibers are not discussed in detail. This review paper discusses all the six types of plant fibers such as bast, leaf, seed, straw, grass, and wood, together with animal fibers and regenerated cellulose fibers. Additionally, the review considers developments dealing with natural fibers and their composites. The fiber source, extraction, availability, type, composition, and mechanical properties are discussed. The advantages and disadvantages of using each biofiber are discussed. Three fabric architectures such as nonwoven, woven and knitted have been briefly discussed. Finally, the paper presents the overview of the results from the composites made from each fiber with suitable references for in-depth studies. [ABSTRACT FROM AUTHOR]

[Display omitted] • Water absorption mechanism of natural fiber composites conforms Fickian's behavior. • Water absorption of composites increases with the fiber loading up to a certain extent. • Chemical treatment and modifier-based additives improve the water resistance of composites. • Hybridization with agro-waste fibers or nanofillers synergistically affects water absorption. • Moisture content of agricultural fiber composites is comparable with the existing materials. With the growing environmental impact related to the production, disposal, and recycling of synthetic fiber based polymeric matrix composites, environmentally friendly composites have been developed using materials based on natural resources. Of late, the disposal of agro-waste from industrial crops is another serious concern in developing countries. Based on the availability of agro-wastes, its usage for the development of sustainable composite materials is on the rise which constitutes a very interesting option for the construction industry. However, the water uptake characteristic of these natural fibers is established to be the most critical factor for the progressive deterioration of resultant composites' properties over time. Present review article attempts to comprehensively report studies related to water absorption properties of agricultural fiber reinforced polymer composites. This study is divided into three sections: The first section highlights the water absorption mechanism including the experimental measurement and prediction using Fickian modelling. The second part outlines the experimental results of water absorption capacity for various composites with different types of thermosets, thermoplastics and agro-wastes. The last section analyses the potentiality of agro-waste materials to partly replace the conventional composites in building material research. The impact of water absorption on the mechanical properties of composites is also demonstrated. The literature survey compares the moisture/water content level of previous findings with the existing wood-based products in service and the established standard requirement for industrial building materials. This review article will provide a comprehensive data source for further research in this topic to explore the application of agricultural fiber-reinforced polymer composites as cheap, primary building construction materials. [ABSTRACT FROM AUTHOR]

Over recent years, enthusiasm towards the manufacturing of biopolymers has attracted considerable attention due to the rising concern about depleting resources and worsening pollution. Among the biopolymers available in the world, polylactic acid (PLA) is one of the highest biopolymers produced globally and thus, making it suitable for product commercialisation. Therefore, the effectiveness of natural fibre reinforced PLA composite as an alternative material to substitute the non-renewable petroleum-based materials has been examined by researchers. The type of fibre used in fibre/matrix adhesion is very important because it influences the biocomposites' mechanical properties. Besides that, an outline of the present circumstance of natural fibre-reinforced PLA 3D printing, as well as its functions in 4D printing for applications of stimuli-responsive polymers were also discussed. This research paper aims to present the development and conducted studies on PLA-based natural fibre bio-composites over the last decade. This work reviews recent PLA-derived bio-composite research related to PLA synthesis and biodegradation, its properties, processes, challenges and prospects. [ABSTRACT FROM AUTHOR]