Natural Fiber Reinforced Polymer Composites Research Articles

Optimized random forest model for predicting flexural properties of sustainable composites

AbstractIn an era of technological advancements, the quest for sustainable products has taken a center stage. The utilization of natural fiber reinforced polymer composites has become crucial in the manufacturing of eco‐friendly products due to their low cost, renewability, biodegradability, and comparable properties to synthetic composites. Coir‐based composites have been utilized in roofing, composite panels, furniture, and bio‐based insulation applications, providing enhanced strength and sustainability. In the current investigation, an exploratory data analysis (EDA) was conducted to understand the relationship between the various input variables and the flexural properties of short coir polymer composites (SCPCs). The data analysis revealed that manufacturing process had a significant impact on the flexural properties of SCPCs. Based on the insights gained from the EDA, an optimized Random Forest prediction model was developed to predict the flexural properties. Genetic algorithm approach for hyperparameter optimization led to lower objective loss in contrast to Bayesian optimized Random Forest model. The model's performance was subsequently evaluated through holdout validation, and the outcome demonstrated the model's proficiency in accurately predicting the properties. The developed model can be used as a tool for optimizing the design of SCPCs for specific applications, by predicting the flexural properties of the composites.Highlights Flexural behavior of short coir polymer composites was analyzed and modeled. Manufacturing process has the highest impact on the flexural properties. Random forest model predicted the flexural properties with high accuracy. Genetic algorithm optimized model further enhanced the model performance. The developed framework provides insights into designing biocomposites.

Effect of alumina fillers on physical and mechanical properties of luffa/groundnut shell natural fiber reinforced polymer composites

AbstractThis study aims to investigate the physical and mechanical properties of epoxy composites reinforced with hybrid luffa waste and groundnut shell waste natural fibers and to evaluate the effect of different filler loadings of alumina on the mechanical behavior of the hybrid composites. The luffa fibers were made to undergo mercerization in 10% NaOH solution. All the treated fibers and the alumina fillers were characterized using X‐ray diffraction analysis (XRD). The study used three different filler loadings of alumina (Al2O3) (5%, 10%, and 15% by volume) and three different fractions of treated luffa‐waste groundnut shell hybrid fibers (10%, 30%, and 50% by volume). The composites were fabricated using the hand layup technique, and the prepared test specimens were subjected to mechanical and physical properties testing as per ASTM standards. The experimental findings indicated that the inclusion of Al2O3 filler improved the physical and mechanical characteristics of the natural fiber‐reinforced hybrid composites. The results showed that the composites with 30 vol. % fibers (1:1 luffa fiber: groundnut shell fiber) and 10 vol. % Al2O3 content showed enhanced tensile, flexural, shear, and impact strength and hardness. Besides, a good synergy between the alumina fillers, natural fibers, and the polymer matrix was observed in the surface morphology of the composite specimen. The developed composites can be used in low and medium‐load‐bearing structural and non‐structural applications.Highlights Development of hybrid polymer composites with luffa and novel groundnut shell fibers Hybridization of alumina ceramic particles with natural fiber hybrid composites Assessment of physical and mechanical properties of the polymer composites

Free vibration analysis of jute/kenaf/banana hybrid biocomposites: effects of various stacking sequences

This work provides an insight of the free vibration behaviour based on experimental modal analysis of hybrid natural fibre reinforced polymer composites fabricated via compression moulding method. This study aims to study the impact of different polymer matrices (vinyl ester and epoxy) and stacking order of different natural fibres (Jute, Kenaf and Banana) on the composite’s free vibration characteristics. Jute-Kenaf-Banana-Epoxy (JKBE) matrix composites exhibited enhanced free vibration properties compared to single fiber reinforcements, except the banana/epoxy composites. Additionally, Jute-Kenaf-Banana-Vinyl ester (JKBV) composites demonstrated improved free vibration properties in comparison to single fiber reinforcements, with the exception of kenaf/vinyl ester composites. Kenaf-Banana-Jute-Jute-Banana-Kenaf-Epoxy (KBJJBKE) and Kenaf-Banana-Jute-Jute-Banana-Kenaf-Vinyl ester (KBJJBKV) hybrid composites showed the highest natural frequencies of 68.36 Hz and 97.66 Hz, respectively. However, there was no significant improvements in the natural frequencies of Jute-Kenaf-Banana-Kenaf-Banana-Jute-Epoxy (JKBKBJE) and Jute-Kenaf-Banana-Kenaf-Banana-Jute-Vinyl ester (JKBKBJV) hybrid composites. The highest damping factor was observed for JKBKBJE (0.153) and JKBKBJV (0.224) hybrid composites. These hybrid composites with better free vibration properties shall be a potential candidate in the automobile interior applications.

Investigation of physical, mechanical, tribological and biodegradable properties of hybrid natural fibre reinforced polymer composite

This study has investigated the effect of natural fibres such as kenaf, coconut and jute and their combination as reinforced in an epoxy polymer matrix natural fiber reinforced polymer (NFRP) on mechanical properties (impact, flexural, tensile strength and hardness), thermal stability, tribological properties and biodegradability. The raw fibres were chemically treated with 3% NaOH for 24 h, and 10 wt.% was blended in the epoxy matrix. Further, a composite surface morphology and fibre dispersion were analysed using a scanning electron microscope. An improvement of an average of 30.39%, 1157.7% and 30.98% in impact strength, hardness and tensile strength, respectively, compared to pure epoxy composite. Further, the tribological study has shown a lesser frictional coefficient (∼0.275) in hybrid NFRP than in other composites where EN31 Steel disc is used as the counterbody. Moreover, the mixed NFRP has demonstrated excellent biodegradable properties compared to other NFRP and pure composites.

In English

Natural fibre reinforced polymer composites nowadays are considered to be attractive cheap, safe and eco-friendly materials. The main problem of such composites related to the hydrophilicity of plant fibres may be successfully solved by chemical modification of their surface. However, some characteristics of the materials may be suppressed after this procedure. Therefore, the aim of the research is to find out the impact of chemical modification of filler on thermooxidative stability, tensile and flexural strength, as well as on biodegradability of polymer composites. The novelty of this work is in the examining new materials on the basis of Si-containing epoxyurethanes and chemically treated hemp woody core (HWC). Woody core that is the side product of hemp industry requiring its apropriate utilization was exposed to mercerization with sodium hydroxide solution and to further functionalization with epoxidized soybean oil (ESO) or 3-aminopropyltriethoxysilane (APS). Raw and surface treated HWC was used as reinforcement for two types of organic-inorganic epoxyurethane matrices made from sodium silicate, polyurethane prepolymer based on polyisocyanate and castor oil, and either diglycidyl ether of bisphenol-A (DGEBA) or ESO as epoxy component. Functionalization of HWC led to better mechanical properties of composites. Compared to the corresponding materials including untreated filler, maximum increase in flexural strength (26 %) was observed for the samples with ESO-containing epoxyurethane and silanized HWC, while maximum increase in tensile strength (53 %) was revealed for the ones with DGEBA-containing epoxyurethane and oil treated HWC. Thermooxidative stability was also higher for composites reinforced with functionalized HWC. The specimens with APS-treated HWC performed the best at thermal decomposition. The values of their T50% were up to 68 °C more than those for composites with unmodified filler. At the same time, the samples based on APS- or ESO-treated HWC were the most resistant to biodegradation, which may be concluded from their smallest weight loss during soil burial test.

Optimizing Biomedical Facilities Performance with Dombeya Fiber-Paper Particle Hybrid Reinforced Epoxy Composites

Since the last two decades, the use of natural fiber reinforced polymer composites has garnered significant application considerations over the synthetic fiber reinforced composites due to their numerous advantages and unique properties. Likewise, epoxy resin has attracted the interest of many researchers for composite synthesis, basically because of its chemical stability, thermal and mechanical characteristics. Hence, the primary aim of this study was to investigate the influence of dombeya fiber and paper particulate on the physical and mechanical properties of dombeya fiber and paper particulate-reinforced polymer composites for structural applications. Dombeya fiber and paper particles are renewable and biodegradable materials, thereby making them environmentally friendly materials to replace synthetic materials. Hand lay-up technique was utilized to fabricate the hybrid-reinforced biocomposites after which they were subjected to mechanical, wear, density, and moisture absorption properties. The surface morphology of the fractured surface was also analyzed to investigate its microstructural features. It was discovered from the results that hybrid biocomposites demonstrated improved properties over the unreinforced composite, with composites from 9-wt% dombeya fiber-paper particles reinforced biocomposite exhibiting the most suitable properties with commensurate density with the unreinforced epoxy matrix. These obtained characteristics support the material as a suitable material for biomedical apparatus application such as orthopedic implants, surgical instruments, and bone fixation devices. 

Exploring the use of natural fiber-reinforced polymer composites in electronic circuit boards

Sustainable banana fiber has become potential alternative reinforcement materials instead of synthetic fibers for the development of the polymer composites. These natural fiber-reinforced polymer composites can be utilized for numerous applications. The current study aims to fabricate the epoxy/banana fiber composites under varying fraction of banana fibers. Compression molding process was employed to fabricate the composites since it is frequently used for production of large-scale composite parts like automotive components. Various weight percentages of banana fiber (50%, 60%, 70%, and 80% by weight) and epoxy (50%, 40%, 30%, and 20% by weight) were utilized for the development of the composites. Results revealed that the combination of the epoxy (40 wt. %)/banana fiber (60%) has the higher tensile strength of 22.67 MPa, flexural strength of 39.56 MPa, impact strength of 2.97 kJ/m2, and Barcol hardness of 35.24 among the various combinations of the epoxy and banana fiber composites. This work highlights the viability of sustainable materials within the materials engineering field, promoting the development of eco-friendly alternatives in composite fabrication.

Bamboo fiber reinforced poly (acrylonitrile-styrene-acrylic)/chlorinated polyethylene via compabilization

In the quest to enhance the performance of natural fiber-reinforced polymer composites, achieving optimal dispersion of fiber materials within a polymeric matrix has been identified as a key strategy. Traditional approaches, such as the surface modification of natural fibers, often necessitate the use of additional synthetic chemical processes, presenting a significant challenge. In this work, taking poly (acrylonitrile–styrene–acrylic) (ASA) and bamboo fiber (BF) as a model system, we attempt to use the elastomer-chlorinated polyethylene (CPE) as a compatibilizer to tailor the mechanical properties of ASA/CPE/BF ternary composites. It was found that increasing CPE content contributed to more remarkable reinforcing efficiency, where composite with 15 phr CPE exhibited a nearly four-fold increase in reinforcing efficiency of tensile strength (20 %) compared with that of composite system without CPE (4.1 %). Such improvement was ascribed to the compatibilizing effect exerted by CPE, which prevented the aggregation of BF within polymeric matrix. Surface properties suggested the stronger interface between CPE and BF compared to that between ASA and BF and thereby contributed to the compabilizing effect. Since no chemical process was involved, it is suggested that the introduction of elastomer to be a universal, green and sustainable approach to achieve the reinforcement.

Experimental investigation on mechanical performance and drilling behavior of hybrid polymer composites through statistical and machine learning approach

The current study focuses on fabricating partially biodegradable composites added with nettle and grewia optiva fibers in epoxy. The mechanical properties of various fiber reinforcement combinations, such as tensile, impact, and flexural strength were evaluated. One of the main issues when drilling natural fiber-reinforced polymer composites is delamination damage. Therefore, the drilling ability of the hybrid composites was investigated by various drilling operation conditions: drill diameter (4, 6, 8 mm), feed rate (0.125, 0.212, 0.3 mm/rev) and spindle speed (400, 600, 800 rev/min). The experimental investigation was carried out using a twist drill at dry and ambient temperatures. The response surface methodology (RSM) was adopted during the investigation and the contribution of feed rate (65.31%) was found as the dominant factor, followed by spindle speed (35.83%) and drill diameter (10.72%) to influence the delamination factor of hybrid composites. The grey relation analysis was further applied to the experimental results to rank the experiments. Scanning electron microscopy was used to examine the fractured surface of tested samples and delamination damage caused by drilling operations. The developed composites offered a maximum tensile strength (34.3 MPa), impact strength (11.13 J) and flexural strength (23.91 MPa) observed in the hybrid composites for a reinforcement combination of 5% nettle and 15% grewia optiva fibers. The prediction models developed by RSM and artificial neural network (ANN) were matched with the investigated results and ANN was noticed to be more accurate than the RSM. The research work will be beneficial for the industries involved in the development of structural panels reinforced with nettle and grewia optiva fibers.

Formulation of a Composite Material for Thermal Comfort from Bamboo Fibers and HDPE Reinforced with Bauxite Red Mud and MAPE: Physico-Mechanical and Thermal Properties

The modern, dynamic world can’t imagine its development without carrying the concept of advancement in composite materials. Various researches are going on in this field to achieve the desired standard. Natural fiber reinforced polymer composite (NFPC) has a huge affinity to interchange the composite made up of synthetic fiber. This is primarily because of the advantages like light-weight, non-toxic, nonabrasive, easy availability, low cost and biodegradable properties. The specific mechanical properties like specific tensile modulus and other specific properties of natural fiber gives a satisfying result for composites as compared to synthetic fiber based composites. The general objective of this work was to develop a composite from bamboo fibers and HDPE reinforced with red bauxite mud residues to ensure good thermal stability and improve the physico-mechanical properties in traction and flexion. The morphology of the composites showed that there was a homogenous dispersion of BF at lower weight fraction, although fibre agglomeration was noticed at higher weight fraction. The results of this study revealed that treated bamboo fibres are suitable for reinforcing HDPE. It appears from these studies that the formulations produced are in accordance with the ASTM standard and can validly be used for the thermal comfort of buildings to improve the comfort of the population in sustainable habitats.

Review on Properties of Natural Fiber Reinforced Polymer Composites: Effect of Gamma Radiation and Nano particles.

Materials comprised of a polymer matrix with natural fiber reinforcement are known as natural fiber reinforcement polymer composites (NFRCs). Scientists have recently become quite interested in these composite materials because they provide improved properties over conventional synthetic fiber reinforced polymer composites at a lower cost and with benefits to the environment. However, a number of factors, including gamma radiation exposure and the addition of nanoparticles, can impact the properties of NFRCs. This review will focus on the effects of gamma radiation and nanoparticles on the mechanical, thermal, and water-resistance properties of NFRCs. In order to help in the creation of new and improved NFRCs for diverse applications, this review seeks to provide a thorough understanding of the characteristics of NFRCs and how they might be impacted by gamma radiation and nanoparticles.

The influence of different fiber sizes on the flexural strength of natural fiber-reinforced polymer composites

This experiment aimed to investigate the impact of varying fiber lengths on the flexural strength of coconut fiber composites with epoxy resin. Coconut fiber composite panels were produced using rectangular molds. The effects of various fiber sizes, especially 2, 4, and 6 mm, respectively, were compared with fiberless and continuous fiber polymer composites on the flexural strength of Natural Fiber-reinforced Polymer Composites (NFPC). The lowest flexural strength is 10.04 MPa, was obtained for the NFPC sample with a fiber length of 2 mm, while the highest flexural strength value was 10.70 MPa with a fiber length of 6 mm. Generally, flexural strength is influenced by variations in fiber size but not significantly. The flexural modulus and flexural strength values exhibit the same trend. Fiber pullouts are visible on the fracture surface of the sample, and voids in the form of trapped gas are also apparent on the sample surface. Short fiber size is one of the causes of fiber pullout, which can reduce the flexural strength of short fiber polymers.

A Systematic Review of Natural Fiber-Reinforced Polymer Composites in Prosthetic Socket Fabrication

This review systematically examines the burgeoning field of natural fiber-reinforced polymer (NFRP) composites in prosthetic socket fabrication. The review begins by exploring the historical context and recent shift towards sustainable and biocompatible materials in prosthetics, with a specific focus on NFRP. It delves into the composition and properties of NFRP, detailing the types of natural fibers used and the characteristics of these innovative composites. The review highlights the advantages of NFRP in prosthetics, notably their biocompatibility, sustainability, and mechanical properties that are pertinent to prosthetic applications. The technical aspects of fabricating prosthetic sockets with NFRP are examined, discussing both traditional and advanced manufacturing techniques and design considerations that take into account anatomical and biomechanical factors, as well as the need for customization. The clinical outcomes and user experiences with NFRP prosthetic sockets are evaluated, focusing on their durability, functionality, and comparison with traditional materials. User-centric perspectives, including comfort, satisfaction, and adaptation challenges, are also considered. Crucial challenges and limitations in the field are identified, such as technical and fabrication complexities, consistency and quality control issues, as well as clinical and practical barriers like accessibility, cost, and the necessity for specialized training. The review outlines future directions and research needs, emphasizing potential innovations in NFRP, integration with emerging technologies, and the importance of translational research and interdisciplinary collaboration. The review underscores the significant role NFRP could play in advancing prosthetic technology, envisioning a future where prosthetic design is not only user-friendly and functional but also sustainable

The effect of different wrapping schemes on the shear capacity of rc beams using the finite element method

Structural strength degradation was a highly important issue in the construction sector. In recent years, studies on the use of Natural Fiber Reinforced Polymer (NFRP) composites as external reinforcement have been started. The innovation of using abaca fibers as a mixture in NFRP composites provides a sufficiently high tensile strength. This innovation has the potential to be further developed to optimize the mechanical properties and applications of the composite. With the current technological advancements, numerical analysis carried out using various software based on finite element methods is one tool to solve the engineering problem. One of them was the ATENA software. This research aimed to strengthen the shear capacity of reinforced concrete beams using abaca FRP composites with various wrapping schemes (two sides wrap, U wrap, and complete wrap). The beams were modeled and analyzed by ATENA software. The solution of this problem was solved using the arc-length method. The numerical analysis results showed an increase in the maximum shear capacity by 11%, 14%, and 18% for two sides, U, and complete wraps, respectively. The crack angle on the complete wrap beam occurred at 37 degrees, and it was the largest among the other beams.

A Review on Composite Material Reinforced With Natural Fibers

Abstract: Materials plays vital role for survival of any manufacturing industry. Conventional materials are replaced by composite material because of their high specific strength, strong damping capacity and high specific modulus. In modern era, natural fiber reinforced polymer composites came into light because of promising properties of natural fibers such as light weight, water resistance, high impact strength, environment friendly etc. In this study, different types of natural fibers that can be used as reinforcement in polymer composite are discussed. Various methods of production and steps involved in processing of natural fiber reinforced composite are presented. Then, mechanical and tribological properties of these composites are reviewed and presented. The different applications of natural fiber reinforced polymer composite are also discussed.

Tensile Properties Characterisation of Hybrid Luffa/GCW Fiber Reinforced Polymer Composite

Extensive research has been conducted on fiber reinforced polymer (FRP) composites, which have demonstrated superior mechanical properties compared to their individual components. In order to add on to current research trends, the use of ground coffee waste (GCW) and Luffa fibers reinforced polyethylene (PE) composites were fabricated to produce a hybrid natural FRP composite. Tensile testing of the composite indicates that the optimum fiber volume to be between 15% and 35%, as the tensile strength exhibited 9.32 MPa and 8.75 MPa, respectively. Similarly, the tensile modulus of the fabricated composite peaked at 25% with 238 MPa, then declined to 173 MPa at 35%. This indicates that the fibers effectively reinforce the polymer matrix, but once the composite reaches its optimal fiber volume, a decrease in both tensile strength and tensile modulus is observed. The reduction in tensile properties can be attributed to an uneven distribution of load-bearing capacity throughout the composite, as the fibers are no longer able to fully support the matrix once the optimal fiber volume is reached. The specific tensile strength and specific tensile modulus also shows that with the inclusion of Luffa fiber and GCW microfiber contributed to a lighter weight composite. In a nutshell, the hybrid composite fabricated using 25% fiber volume exhibited a tensile strength almost similar to its neat matrix counterpart, though has a noteworthy value in terms of its tensile modulus. The hybrid composite can be as strong in terms of tensile strength, but far more significant in its rigidity, in comparison to the neat polyethylene laminate. Therefore, it showed that the hybrid natural Luffa/GCW FRP has the potential in the engineering industry, such as lightweight furniture, household appliances, automotive parts, and other composite engineering applications.

Impact of Fused Deposition Modeling Process Parameters and Heat Treatment on Mechanical Characteristics and Product Quality: A Review

Fused Deposition Modeling (FDM) is indeed one of the most commonly used methods of additive manufacturing, particularly for printing polymers and fiber-reinforced polymer composites. When compared to more conventional production meth ods like injection molding, the key benefits of FDM include producing components with intricate shapes, minimal material wastage, shorter production times, and lower costs because no tooling is needed. However, the strength and surface quality of the product produced using this technique are lower, that can be improved by selecting the optimized design variable and applying heat treatment depending on how the product will be used in an industry. This review paper provides an overview of the effect of different process parameters on mechanical properties, print time, and surface characteristics of the parts made of polymers and fiber-reinforced polymer composites in addition to the challenges encountered during the printing of composites. It also discusses the new material’s development, such as natural fiber-reinforced polymer composites, the impact of heat treatment, and the void formation influence on the mechanical properties, build time, dimensional accuracy, and surface finish of 3D-printed parts.

The Improvement of the Tribological Behaviour of Chemically Treated Abaca Fibre-Reinforced Polymer Composites.

Abaca fibres that have excellent mechanical properties are widely applied in the production and preparation of eco-friendly polymer composites as reinforcement materials. However, the weak interfacial bonding property of the abaca fibre and composite matrix limits the further extended application of abaca fibre-reinforced polymer composites. In this research, the findings demonstrate that, compared to raw abaca fibres, the interfacial shear strength (IFSS) value between the treated fibre and matrix is improved by 32% to 86%. Moreover, chemically treated abaca fibres could not only improve the wear resistance of the polymer composites, but also could promote the formation of primary and secondary plateaus. The best wear resistance behaviour was demonstrated by the sample with abaca fibres treated with 3% NaOH and 5% silane solutions, which had a maximum reduction in the sum wear rate of 28.44%. This research will provide detail on theoretical guidance and technical support for the development of eco-friendly natural fibre-reinforced polymer composites.

A Review on Mechanical Properties of Natural Fibre Reinforced PLA Composites

Abstract: Presently, scientists and researchers are in an endless quest to develop green, recyclable, and eco-friendly materials. Natural fibre reinforced polymer composites became popular among materialists due to their lightweight, high strength-to-weight ratio, and biodegradability. However, all-natural fibre reinforced polymer composites are not biodegradable. Polymer matrices like poly-lactic acid (PLA) and poly-butylene succinate (PBS) are biodegradable, whereas epoxy, polypropylene, and polystyrene are non-biodegradable polymer matrices. Besides biodegradability, PLA has been known for its excellent physical and mechanical properties. This review emphasises the mechanical properties (tensile, flexural, and impact strengths) of natural fibrereinforced PLA composites. Factors affecting the mechanical properties of PLA composites are also discussed. It also unveils research gaps from the previous literature, which shows that limited studies are reported based on modeling and prediction of mechanical properties of hybrid PLA composites reinforcing natural fibres like abaca, aloe vera, and bamboo fibres.

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.