Natural Fiber Composites Research Articles

Hemp fiber reinforced dual dynamic network vitrimer biocomposites with direct incorporation of amino silane

Natural fiber composites are inexpensive and renewable alternatives to traditional fiber reinforced polymers (FRPs). However, existing natural fiber composites primarily rely on petrochemical based thermosetting matrices, which are difficult to recycle due to their stable crosslinked network structures. To address this challenge, it is desirable to develop natural fiber composites with inherently recyclable biobased matrices. In this study, we developed a dual dynamic network vitrimer matrix from hempseed oil and limonene derivatives and demonstrated its application in hemp fiber reinforced composites. To improve the weak interface between hemp fiber and the polymer matrix, a common challenge in the realm of natural fiber composites, we directly incorporated amino silane into the vitrimer matrix. The amino silane participated in the polymer network, increasing the crosslink density and toughening the matrix, as evidenced by the significant improvement of impact strength from 3.5 kJ/m2 to 10.3 kJ/m2. Moreover, the incorporation of amino silane resulted in a lower water absorption by 11 % in a 7-day soaking for the composites, demonstrating improved fiber/matrix interfacial interaction. Furthermore, our biobased vitrimer matrix exhibits both imine and hydroxy-ester dynamic bonds, which enable the recycling of the biocomposite through a mild and cost-effective aminolysis process (100 °C, 3 h, ambient pressure). The decomposed polymer matrix was successfully reused as a polyol for polyurethane adhesives, and the surface morphology of recovered hemp fibers was analyzed and compared with that of the original fibers. These findings will help broaden the use of vitrimers for practical natural fiber composite applications, raise awareness of the problem of recycling natural fiber composite waste, and shed light on the interfacial challenge of natural fiber reinforced vitrimer composites.

Influence of Anatomy, Microstructure, and Composition of Natural Fibers on the Performance of Thermal Insulation Panels.

The growing interest in environmentally friendly materials is leading to a re-evaluation of natural fibers for industrial applications in order to meet sustainability and low-cost objectives, especially for thermal insulation of buildings. This paper deals with the chemical and physical characterization of fibers extracted from seagrass (Posidonia oceanica) and alfa grass (Stipa tenacissima) for a possible substitution of synthetic materials for thermal insulation. Hemp (Cannabis sativa), a fiber broadly used, was also studied for comparison. The parameters characterized include porosity, thermal degradation, elemental composition, skeletal and particle density of the fibers as well as investigation of the thermal conductivity of fiber-based panels. Several technologies were involved in investigating these parameters, including mercury intrusion, thermogravimetric analysis, fluorescence spectroscopy, and fluid pycnometry. The fibers showed a degradation temperature between 316 and 340 °C for Posidonia, between 292 and 326 °C for alfa, and between 300 and 336 °C for hemp fibers. A high porosity allied with a reduced pore size was revealed for Posidonia (77%, 0.54 μm) compared to hemp (75%, 0.61 μm) and alfa (57%, 2.1 μm) raw fibers, leading to lower thermal conductivity values for the nonwoven panels based on Posidonia (0.0356-0.0392 W/m.K) compared to alfa (0.0365-0.0397 W/m.K) and hemp (0.0387-0.0427 W/m.K). Bulk density, operating temperature, and humidity conditions have been shown to be determining factors for the thermal performance of the panels.

Natural Fibers Composites: Origin, Importance, Consumption Pattern, and Challenges

This comprehensive review explores the multifaceted world of natural fiber applications within the domain of composite materials. Natural fibers are meticulously examined in detail, considering their diverse origins, which encompass plant-derived fibers (cellulose-based), animal-derived fibers (protein-based), and even mineral-derived variations. This review conducts a profound analysis, not only scrutinizing their chemical compositions, intricate structures, and inherent physical properties but also highlighting their wide-ranging applications across various industries. The investigation extends to composites utilizing mineral or polymer matrices, delving into their synergistic interplay and the resulting material properties. Furthermore, this review does not limit itself to the intrinsic attributes of natural fibers but ventures into the realm of innovative enhancements. The exploration encompasses the augmentation of composites through the integration of natural fibers, including the incorporation of nano-fillers, offering a compelling avenue for further research and technological development. In conclusion, this review synthesizes a comprehensive understanding of the pivotal role of natural fibers in the realm of composite materials. It brings together insights from their diverse origins, intrinsic properties, and practical applications across sectors. As the final curtain is drawn, the discourse transcends the present to outline the trajectories of future work in the dynamic arena of natural fiber composites, shedding light on emerging trends that promise to shape the course of scientific and industrial advancements.

A Comprehensive Review of Natural Fibre Reinforced Polymer Composites

The idea of composite materials is introduced in this article, with an emphasis on composites made of natural fibres and polymers. Composites are made up of various elements or phases that significantly affect the material's general characteristics. The matrix, the continuous phase, is typically made up of ceramics, metals, or polymers. Natural fibres that provide strength and stiffness make up the reinforcement component in natural fibre-reinforced composites. These composite materials have uses in the consumer goods, packaging, sports, and construction industries, in addition to providing environmental advantages. The paper presents a review of the literature on the creation and characterization of composites reinforced by natural fibres. To improve the mechanical, thermal, and chemical properties of the composites, numerous studies have looked at various kinds of natural fibres, surface modifications, coupling agents, and processing methods. The benefits and drawbacks of using natural fibres in composites are discussed in the article. It gives a general overview of how natural fibre-reinforced polymer composites have evolved and what uses they might have in the future. The article highlights current research initiatives and difficulties in enhancing the performance and compatibility of natural fibres with polymer matrices. The research advances the use of natural fibre composites as environmentally friendly substitutes across a range of industries by fostering a better understanding of their advantages and disadvantages.

Effect of abrasive grit grade on the abrasion wear behaviour of long banana-jute fibers reinforced hybrid epoxy composites

The effect of abrasive grit geometry on two-body abrasion wear behavior of long banana and jute fiber reinforced epoxy composites has been investigated. Epoxy (EP), Epoxy/4 wt% Banana fiber (BF)/4 wt%Jute fiber (JF) (EP8), Epoxy/8 wt%BF/8 wt%JF (EP16), Epoxy/12 wt%BF/12 wt% JF (EP24), and Epoxy/16 wt% BF/16 wt%JF (EP32) were the composite materials systems used for the investigation. These composites were processed and fabricated using hand—lay-up technique. The two body abrasion wear test was carried out in accordance with ASTM G99 under the influence of different SiC grit particles (180, 320, 400, and 600 SiC grit). The test was conducted at a room temperature under the abrasion load of 10 N and abrasion speed of 1 m s−1 over a distance of 100 m. The findings of the experiments revealed that wear response of composites depends on pressure, geometry of abrasion particles and their composition. The wear volume loss and specific wear rate decreases with increase in the rank of grit grade. Further, 16 wt% of fibers in composites exhibits the superior abrasion wear resistance. But the higher volume fraction of natural fibers in composites impaired the abrasion wear resistance. Higher rank of grit number was associated with the lesser wear volume loss because of the change in wear mechanism from abrasion to adhesion. In comparison to epoxy based composites, EP16 composite shows superior wear resistance. SEM images were used to examine the worn surfaces.

Thermo-Physical Analysis of natural fiber reinforced phenol formaldehyde biodegradable composites


 
 
 
 Natural fiber reinforced composites are composite materials which contain reinforced fibers from natural sources. Natural fiber composites can provide an effective and renewable solution for environment-friendly construction materials. For example, building insulation materials which are made of natural fibers can improve energy efficiency and reduce material waste generation. The fibers used in these composites are extracted mainly from plant sources such as bamboo, jute, sisal, and flax. Natural fibers have excellent mechanical and energy-dampening properties, making them ideal for manufacturers looking to replace traditional synthetic fiber reinforcements. They are also gaining popularity as replacements for plastic and metal components in many consumer goods. In this paper desert plant prosopis juliflora fibers were used as reinforcement in phenol formaldehyde resin to make composites. TGA, DSC and DMA were performed to analyze the change in thermal stability and mechanical properties of the prosopis juliflora fiber reinforced phenol formaldehyde composites. The alkali-treated fibers were prepared by immersing the PJ fibers in a 1% sodium hydroxide solution for 24 hours. The fibers were washed and dried before being mixed with the phenol formaldehyde resin. The composites were prepared with untreated and alkali-treated reinforced fibers. All specimens were left to cure at room temperature over night.
 
 
 

Enhancing mechanical properties of natural fiber composites: a study on the effects of fiber loading and filler addition

In this research, we conducted an extensive analysis of two distinct composite materials: NWBF/EP (nonwoven banana fiber/epoxy) and NWBF/EP/WNP (nonwoven banana fiber/epoxy with walnut powder). These composites were meticulously engineered, utilizing epoxy as the matrix, nonwoven banana fiber as the primary reinforcement, and walnut powder as the secondary reinforcement. Our investigation unveiled that the NWBF/EP/WNP hybrid composite exhibits superior mechanical properties in comparison to the NWBF/EP composite. Notably, the BW4 hybrid composite demonstrated a substantial increase in tensile strength, reaching an impressive 76.7 MPa. This enhancement underscores the potential for augmenting composite stiffness by elevating the WNP ratio up to a specific threshold, though exceeding this threshold leads to a reduction in epoxy resin content. Furthermore, our study revealed substantial improvements in flexural strength as WNP was introduced, with a noteworthy 5.8% rise at a 5% weight percent WNP loading. The pinnacle of flexural strength, 43.6 MPa, was achieved at a 20% weight percent loading. Impact toughness also displayed significant improvements, with the highest impact strength (5.2 J) observed in BW3. This highlights the potential for enhancing the toughness of the hybrid composite within a defined WNP weight percent range. We also gained valuable insights into hardness, void fraction, and the influence of walnut powder. The addition of walnut powder increased void fraction, reduced density, and enhanced various mechanical properties. Our evaluation of wear performance emphasized the pivotal role of factors such as sliding velocity, fiber content, sliding distance, and normal load. In conclusion, this research not only elucidates the mechanical advantages of the NWBF/WNP/epoxy hybrid composite but also offers critical insights for potential applications. The findings underscore the potential of these hybrid composites to serve as sustainable and competitive alternatives to synthetic fiber products in a range of engineering and manufacturing contexts.

Thermal Insulation of Roof using Composite Materials

Due to industrialization and urbanization the temperature is constantly rising day by day. Conventional roofs used by low-income community/society like metal, steel, aluminium, copper, etc will absorb heat and increases room temperature which creates discomfort for the people. Use of natural fibre composites as a roof material are said to have benefits for the environment. There is an expansion in the usage of natural composite materials as it helps to decrease the room temperature and provides the comfort for the users. In this research paper, an attempt will be made to develop composite materials for layering of roof using sugarcane bagasse and polymer. The composite formed by using both waste materials like sugarcane bagasse and polymer will be tested in terms of various parameters like thermal conductivity, tensile strength and impact test.

Sound Absorption Performance of Coir Fiber/Polylactic Acid Composite Microperforated Panel

Microperforated panel (MPP) is considered a unique and promising sound absorber, as its sound absorption performance depends on parameters such as perforation ratio, perforation diameter, and air gap thickness. In this study, the MPP was fabricated through conventional mixing, granulating, and hot compression methods. The MPP was made from coir fiber/polylactic acid (PLA) composite, outside the norm of using metallic materials to produce MPP. The panel's sound absorption performance was measured using an impedance measurement tube and then compared with pure PLA MPP, which was taken as a benchmark for this study for a fair comparison. The MPP produced in this study demonstrated outstanding sound absorption performance due to its porous and tortuous structure. The porous and tortuous structure coincided with the perforated hole mechanism in absorbing sound; thus, the performance was better than pure PLA MPP, which did not possess an apparent porous and tortuous structure. This study proved that natural fiber composite has considerable potential to be used for MPP production, as it is a sustainable and natural resource that brings less harm to the environment compared to the common usage of metallic materials.

Acoustic, vibration, and viscoelastic performance of wire EDM waste-reinforced natural fiber composites

Natural fiber composites are being promoted as cost-effective substitutes for synthetic materials due to its benefits like lightweight, recyclability, cost, and biodegradability. The main objective of the present work is to reuse the electrical discharge machining (EDM) waste wire in coated hemp/ramie fiber epoxy composites. The wire lengths of 1, 3, and 5 cm were used as reinforcement in composites and its effects were studied through mechanical characterizations, dynamic mechanical analysis (DMA), acoustic study, and vibration behavior. The 5 cm wire length composite (S4) secured better mechanical properties (tensile-26%, impact-33%, hardness-12%). Additionally, S4 displayed increased storage modulus and reduced loss modulus from DMA analysis. The natural frequency has increased by 15%, whereas decrease in damping ratio was observed for S4. The sound absorption coefficient of S4 composite was lower compared to S1 due to the stiffness and lower damping properties of the reinforced wire. The developed composite can provide the necessary strength and stiffness while reducing the overall weight of the vehicle in an automobile industry.

Static, dynamic and impact properties of a high-performance flax-fiber composite

As environmental issues become increasingly relevant nowadays, the need to develop new materials entirely or partially based on renewable resources is one fundamental step to reduce the consumption of fossil fuels and CO2 emissions. In that sense, natural fiber composites might represent an environmentally sustainable alternative to conventional solutions such as glass and carbon fiber composites, standard today for many lightweight structural applications; however, solutions are several and diverse in terms of technological process, base materials, mechanical properties, and analysis of their behaviour, necessary for safe industrial use, is still lacking for most resin-fiber combinations. Consequently, this work presents a comprehensive material characterization of a flax-fiber reinforced composite material, analyzing both the static and dynamic mechanical performances, targeting future crashworthiness applications. In particular static tensile, compressive, flexural and shear properties were investigated, while low-speed indentation, high strain-rate tensile and ballistic tests were carried out to probe the dynamic and impact features.

Effects of alkaline treatment and manufacturing process on mechanical and absorption properties of Wild Abyssinia Banana fiber reinforced epoxy composite

To enhance the properties of natural fiber composite, proper selection of an optimum alkaline concentration for fiber surface modifications and composite manufacturing techniques are the main criteria to be considered. This study examined how NaOH and manufacturing methodsaffect the mechanical and absorbency characteristics of a Wild Abyssinia Banana (WAB) epoxy composite. 2 %, 5 %, and 7 % (w/v) NaOH concentrations; hand-layup and hydraulic press manufacturing techniques have been considered. Petroleum, diesel, distilled, and artificial lake water (wastewater) were used for the absorption test. A 5 % NaOH treatment improves composite tensile, flexural, and impact strengths by 14.78 %, 8.59 %, and 29.63 %, respectively. Moreover, the 5 % NaOH treatment reduced the absorption rate of the WAB fiber composite. Hydraulic press manufactured untreated WAB fiber composite was observed to have 26.27 % and 13.45 % higher tensile and flexural strengths than hand layup. The treated WAB fiber-reinforced composite can be utilized in gas stations, home appliances, and finishing materials for construction applications.

Comparing non-biodegradable plastic with environmentally friendly natural fibre composite on car front bumpers design

Production of plastic is growing, and plastics are used in a variety of products. However, plastics are not biodegradable and do not decompose easily. To overcome the problems in decomposition of plastics, the use of a specific type of natural fibre composite (NFC) material for front-bumper in cars is considered in this investigation. NFCs have the advantages of being environmentally friendly, light weight and high strength. The use of jute fibre is adopted for the design of a car front bumper and compared with the plastic bumper through Finite Element Analysis. The aim is to identify their performances in terms of impact energy, strength and resilience. The results show that when both materials were simulated under the same impact force, jute fibre has a lower equivalent stress with 177.1 MPa compare with 293.18 MPa on plastic material. This finding indicates that jute fibre has greater yield limit and more resilient to fracture. The simulation result also shows that jute fibre has a higher equivalent stress of 65.55 MPa on the front bumper compare with a lower equivalent stress of 39.94 MPa on plastic. This suggests that plastic material will yield soon when an impact force is higher. The total deformation after the same impact force in jute fibre is 2.1 mm, which is significantly less than the deformation in plastic with 11.7 mm. Therefore, this research concludes that jute fibre can potentially replace plastic as a green composite material application to minimise environmental damages.Graphical abstract

Natural Fiber Composite Filaments for Additive Manufacturing: A Comprehensive Review

This research explores the potential and significance of 3D printing natural fiber composite (NFC) materials. The primary objective is to investigate the mechanical, thermal, and environmental properties of NFC filaments, mainly focusing on biodegradable, renewable fibers such as jute, hemp, flax, and kenaf. In addition to studying the properties of NFCs, our research delves into the challenges associated with processing, including moisture absorption and fiber-matrix interfacial bonding. The novelty of this work lies in the convergence of traditional composite materials with the versatility of 3D printing technology. NFC filaments offer unique advantages in terms of sustainability, and we examine their potential contributions to the circular economy. By using eco-friendly NFC materials in 3D printing, we aim to present a viable, environmentally responsible alternative to conventional synthetic composites. The importance of 3D printing NFCs stems from the ways their use can align with sustainability goals. These materials provide the advantages of renewability, reduced carbon impact, and in some cases, biodegradability. Their applications extend to various industries, such as automotive, construction, and packaging, where eco-friendly materials are increasingly sought. Such applications showcase the ways in which NFC-based 3D printing can contribute to a more environmentally responsible and sustainable future. This research explores the mechanical, thermal, and environmental properties of NFC materials, highlighting their unique advantages for 3D printing and the potential to have eco-friendly applications in diverse industries.

Effect of hybrid eco‐friendly reinforcement and their size on mechanical and flame retardant properties of polypropylene composites for technical applications

AbstractWhile the potential of natural fiber (NF) composites for various engineering applications is well‐recognized, a deep understanding of the intricate interactions within these composites remains crucial. This study examines the microstructural characteristics of the polymer matrix and evaluates the impact of reinforcement size, with a particular focus on fire sensitivity. Hybrid‐reinforced polypropylene (PP) composites were introduced using a unique tri‐hybrid system. This system combines long flax fibers (LFF) as primary reinforcement, with short basalt fibers (BF) and micro rice husk powder (RHP) as secondary reinforcements. These composites were fabricated using innovative extrusion, compression, and injection molding techniques. This novel fabrication method and strategic hybrid design bridged gaps in the composite structure, leading to significant enhancements in tensile and flexural strength. Improvements of 57.82%, 67.53%, and 60.02% over LFF/PP composites were observed, respectively. On the thermal front, the char residue surged by an impressive 497.51%. Flame properties, notably pHRR and THR, were reduced by 57.25% and 13.28%, respectively. These enhancements are attributed to the lignin in BF and the silica in RHP. The fire safety index further confirmed these improvements, with FGI and FPI increasing by 27.33% and 111.11%, respectively.

An Overview of the Additive Manufacturing of Bast Fiber-Reinforced Composites and Envisaging Advancements Using the Patent Landscape.

Natural fiber composites attract attention owing to their environmentally friendly attributes. Many techniques, including fiber treatment, coatings, and fiber orientations, are used to improve the strength of natural fiber-reinforced composites. Still, the strength needs to be improved as expected. At present, some automation in manufacturing is also supported. Recently, additive manufacturing (AM) of natural fiber-reinforced composites has attracted many researchers around the globe. In this work, researchers' attention to various natural fibers that are 3D printed is articulated and consolidated, and the future scope of the additive manufacturing of natural fiber-reinforced composite is envisaged using the patent landscape. In addition, some of the advancements in additive manufacturing of natural fiber composites are also discussed with reference to the patents filed lately. This may be helpful for the researchers working on AM of natural fiber composites for taking their research into new orientations.

Effect of weight percentage on physical and mechanical properties of coconut shell reinforced polymer composite

The utilization of natural fibers in composites has been increasing and developed to save the environment by using biodegradable materials. Synthetic fiber has many disadvantages than natural fiber such as lower mechanical properties, high cost, and higher environmental risk. Therefore, this study aims to develop natural fiber composites that are reinforced with coconut shell waste and study the effect of weight percentage (wt%) on their physical and mechanical properties. Testing samples were produced from coconut shell reinforced and polyester resin matrix. Coconut shell powder with a particle size of 500 μm and below is randomly distributed into polyster resin matrix. The coconut shell wt% varies from 10% to 30%. The physical and mechanical properties of the composite are determined by collecting data from the density test, hardness test, and tensile test performed based on ASTM standards. The finding results showed that the physical and mechanical properties of coconut shell reinforced polymer composite are influenced significantly by the wt% of coconut shell. The maximum tensile strength was achieved at 15% wt% of the coconut shell.

Selection and processing of natural fibers and nanocellulose for biocomposite applications: A brief review

In this study the recent developments in raw materials, manufacturing processes, and applications of natural fiber composites (NFCs) were reviewed. Natural fibers can represent a substitute for man-made fibers (including glass, aramid, and carbon) in a variety of biocomposite applications. Physical and chemical properties of the natural fibers are given and compared with the synthetic fibers. Advantages and disadvantages of NFCs in comparison with synthetic fibers such as glass and carbon fibers have been proposed. Criteria are described for the selection and processing of natural fibers for polymer composites used in different sectors such as automotive and building industries. The nanocellulose production methods, unique properties, and its recent industrial application in various sectors are given. This short review on NFCs considers their chemical, physical, and mechanical characteristics, as well as their various applications.

Tribological, mechanical, and metallurgical performance of natural fiber-reinforced composites: A comprehensive review

Composite materials have an ever-increasing demand for their application in numerous applications such as aerospace, automobile, petroleum, etc. These materials vary according to their chemical composition, properties, manufacturing techniques, etc. Natural fiber-reinforced composites are the composites where natural fibers such as plant, animal, and mineral fibers are used as reinforcement material. Reinforcement of these fibers yields composite material with extensive properties such as high strength, durability, reliability, etc. These properties lead them to commercial applications in several areas. Therefore, this paper describes various characteristics of the matrix, reinforcement, and resin used for natural fiber composite materials. Also, multiple parameters that affect the growth of these composites are investigated. The tribological behavior of natural fiber composites is focused mainly on friction, wear, and lubrication. Furthermore, the material's mechanical performance and metallurgical behavior are also given significant importance. These materials’ application in various fields is explored separately, and multiple conclusions are drawn.

Matrix-Material Fabrication Technique and Thermogravimetric Analysis of Banana Fiber Reinforced Polypropylene Composites

From the environmental consideration, it would be very interesting to use natural fibers such as banana, jute or coir as reinforcement materials instead of artificial fibers or any kind of synthetic materials. Natural fibers have many advantages over synthetic ones. Polypropylene banana fiber composites (PPBC) are prepared using untreated and alkalitreated banana fibers at 10-25% by weight of the fiber loading. The thermal properties of polypropylene natural fiber composites are very important for technological uses. Thermogravimetric measurements show that the incorporation of banana fiber into PP enhances the thermal stability of composites containing treated fibers, in comparison with untreated fibers. A composite of biodegradable polypropylene (PP) reinforced with short banana natural fibers was prepared by melt blending followed by a hot press molding system. The thermal properties of matrix materials were studied using thermogravimetric analyzers TGA units. It is observed that the introduction of short banana fibers slightly improved the thermo oxidative stability of PP-banana composites. Physical and chemical changes occurred through dehydration, phase transition, molecular orientation, crystallinity disruption, oxidation and decomposition, and incorporation of several functional groups. Systematic investigations of the thermal behavior of polymers in gas, vacuum or inert atmosphere give the knowledge of how change takes place in polymers. To understand such changes thermogravimetric analysis (TGA) and thermal analysis (TG) were performed. It is observed reinforcement of short banana fiber leads to little improvement in the thermooxidative stability of PPBC. Due to the enhancement of thermo-mechanical properties, such composites may be used as building materials namely roof materials, selling materials and many other engineering applications.