Mechanical Properties Of Natural Fibers Research Articles

Effect of Nano Additive on Mechanical Properties of Natural Fiber Reinforced Soil

ABSTRACT Organic soil is a poor bearing medium and is susceptible to uncharacteristic volume change and settlement behavior. Geotechnical design of substructures in organic soil is often of high economic value to account for its weak geotechnical properties. Fiber reinforcement improves the strength of the soil. However, fibers act as a mechanical reinforcement in soil mass rather than enhancing the intrinsic nature of the soil. But chemical additives alter its behavior, thereby improving its strength. This study investigates the strength and hydraulic conductivity (HC) of low plastic organic silt reinforced with banana fiber and nano-silica. Banana fiber was added in dosages of 0.25%, 0.50%, 0.75% and 1%. The optimum fiber dosage was 0.75%. Nano-silica was added to the 0.75% banana fiber reinforced soil at dosages of 0.2%, 0.4%, 0.6% and 0.8% to improve the strength of the reinforced soil. The effect of aging on HC and unconfined compressive strength (UCS) was studied for a period of 90 d. Results showed that nano-silica and banana fiber beneficially complemented each other in the enhancement of geotechnical properties. Nano-silica increased the strength of fiber-reinforced soil, and banana fiber averted the brittle failure nature imposed by the nano-silica. Also, it improved drainage characteristics through aggregation action.

Fabrication and Characterization of Cement-Based Hybrid Concrete Containing Coir Fiber for Advancing Concrete Construction

Nowadays, the incorporation of natural fiber, such as coir fiber, to high-strength concrete has sparked a lot of attention in the construction materials industry. This is because coir fibers are significantly cheaper and more widely accessible than synthetic fibers. Natural fibers such as bamboo, flax, hemp, and coir have distinct microstructures and chemical compositions from cement-based materials. The physical and mechanical properties of natural fiber, such as coir fiber, are significantly correlated with fiber concentration and cellulose component. However, coir fiber has high stretching to failure, while bamboo, flax, and hemp fibers are very resistant to stress and increase stiffness. Based on these distinctive fiber qualities, it is anticipated that coir fiber would facilitate the development of cement-based materials for advanced concrete building applications. In this paper, coir fiber-reinforced cement-based concretes were evaluated in terms of workability, compressive strength, flexural strength, splitting tensile strength, modulus of elasticity, and permeability. The relationship between strength and fiber content was analyzed to understand the impact of coir fiber on the properties of coir fiber-reinforced cement-based concrete. Based on the results obtained, it is determined that 2% coir fiber modification offers the highest compressive strength, splitting tensile strength, and flexural strength. Moreover, the modulus of elasticity is increased, and the permeability is plummeted by the volume fractions of coir fiber 1%, 2%, and 3% because the blending of coir fiber has a bridging and dispersing mechanism of the force-carrying capacity in concrete. In conclusion, coir fiber might be a viable choice for improving the strength and durability of concrete. Therefore, the sparing use of coir fiber presented in this research can be implemented for the manufacturing of concrete in the future.

Effect of epoxy concentrations on thermo-mechanical properties of kenaf fiber – recycled poly (ethylene terephthalate) composites

The effect of different concentrations of epoxy surface coating treatment on the thermal and mechanical properties of kenaf fiber reinforced recycled poly (ethylene terephthalate) (RPET) composites was studied. Silane-treated kenaf fibers (SKF) were epoxy-coated with optimized coating concentrations (in the ratios of 1:4, 1:5, and 1:6 epoxy to acetone solutions) to improve the thermal degradation/decomposition resistance and interfacial bonding with RPET matrix. The different epoxy coated-silane treated kenaf fibers 1:4 ESKF, 1:5 ESKF, and 1:6 ESKF were compounded with RPET at an optimized temperature of 240°C, and their constituents’ composites KF/RPET, 1:4 ESKF/RPET, 1:5 ESKF/RPET, and 1:6 ESKF/RPET were subjected to thermal, mechanical and microstructural investigation. The obtained results showed some remarkable effects of epoxy concentrations on the chemical and surface structures of the treated fibers. Thermal properties of both ESKF and ESKF/RPET composites were more stable and improved with different concentrations of epoxy treatment compared to the untreated counterparts. 1:4 ESKF and 1:5 ESKF were the most thermally stable with onset degradation and DTG decomposition temperatures of 331.6°C and 381.7°C, and 324.0°C and 388.7°C respectively. Mechanical properties of the epoxy-coated composites were higher and further improved with epoxy concentrations and fiber loadings compared to uncoated composites. Hence, the epoxy concentration of 1:4 gave the maximum tensile and impact properties, and at 10 wt. % fiber loading within the lower loading regions, followed by 1:5 with outstanding flexural properties. The coated-treated composites showed strong fiber/matrix bonding with no evidence of fiber decomposition compared to the untreated composites with poor fiber/matrix interaction. The current research findings are original and valid for improving the thermal degradation resistance and stability of natural fibers, and the mechanical properties of natural fiber reinforced engineering thermoplastic composites. The epoxy coated – silane-treated textile kenaf fibers reinforced with recycled PET composites have the potentials to be utilized in high-temperature industrial and engineering applications.

Mechanical Properties of Natural Fibre Reinforced Geopolymer Composites: A Review

The cement production consumes many natural resources and energy, pollutes the environment, and cannot meet the current building materials’ green and sustainable development requirements. Therefore, geopolymers have gained popularity as cement replacements in recent years. Geopolymers have promising characteristics such as low energy consumption and carbon footprint, valuable compressive strength, fire resistance, flame resistance and good durability. However, these materials suffer from low tensile and flexural strength. Hence, fibres are added to overcome these issues and enhance their toughness index. Natural fibres are biodegradable, low-cost, renewable materials and widely available in many countries. This article reviewed previous Natural Fibre Reinforced Geopolymer Composites (NFRGC) studies, focusing on compressive strength, tensile and flexural strengths, and toughness. In addition, the available literature on the effect of the treatment methods of natural fibres on the mechanical properties of NFRGC has been addressed. The findings indicate that adding the appropriate type and content of natural fibres to geopolymer composites can enhance their mechanical properties. However, more attention should be paid to the effects of the pre-treatment of natural fibres on the performance of NFRGC.

A novel integrated BPNN/SNN artificial neural network for predicting the mechanical performance of green fibers for better composite manufacturing

Since the mechanical properties of green cellulosic fibers are only determined experimentally with high diversity, introducing prediction methods for such intrinsic properties of fibers based upon chemical composition is of paramount importance. In this work, double integrated artificial neural networks are utilized to perform novel predictions and classifications of the intrinsic mechanical properties of natural fibers to enhance their implementations in green bio-composites. The predictions and classifications were based upon the green fibers’ chemical composition. The developed model was built up utilizing experimental data for mechanical properties of various cellulosic fiber types commonly used in natural fiber reinforced composites. The first stage back propagation neural network (BPNN) was developed to predict the intrinsic mechanical properties, while the second stage was used to classify the natural fibers based upon shallow neural networks (SNN). The second layer of the model was built based upon shallow neural networks that was capable of classifying the natural fibers. The SNN model was built with 20 hidden layer size and the number of output neurons was set to 11, which equals to the number of fibers classes specified by the dataset. The developed model was capable of predicting all of Young’s modulus, ultimate tensile strength, and elongation at break properties from only two intrinsic properties of fibers; cellulose and moisture content. The overall percentage for the correct classifications was 95.6%, which had demonstrated that machine learning offers a robust approach to classify the fibers based on their intrinsic mechanical properties. The presented model would dramatically help designers and engineers to enhance their selections of various cellulosic fibers for better reliable green composite material performance.

The influence of structural and chemical parameters on mechanical properties of natural fibers: a statistical exploratory analysis

Abstract Due to environmental challenges, the demand for natural fibers (NFs) in biocomposites is expanding. Therefore, the study of the mechanical behavior of these natural fibers is increasingly requested. There is more than two thousands species of plant fibers that have been investigated. In this work, a statistical study involving, namely chemical content, mechanical and physical properties is conducted on a set of natural fibers. The relationship between these factors is studied. The Pearson correlation method is applied to investigate the sensitivity between these parameters. For this aim, a selected data set, collected from the literature, has been used. Results show that Young’s modulus exhibits greater correlation with physical and chemical parameters compared to the other mechanical properties. Additionally, the crystallinity index (CI) is a reliable parameter on predicting the mechanical behavior of natural fibers. Moreover, although the MFA° and diameter are important parameters for NFs modeling purpose, the experimental measurement of these two quantities is a source of unbiased interpretation that partially explains the large variation of the mechanical properties, reported in the literature.

WITHDRAWN: Mechanical properties of natural fiber reinforced polymer composites: A critical review

The article has been withdrawn as requested by the author.Please see Elsevier policy on article withdrawal (https://www.elsevier.com/locate/withdrawalpolicy).

Development of Dioscorea alata stem fibers as eco-friendly reinforcement for composite materials

The use of natural fibers instead of synthetic fibers has become a hot topic in the reinforced composite manufacturing industry. However, there are considerable differences in the mechanical properties of natural fibers cited in the literature. These differences could be due to the prevalent use of monothetic analysis. In this paper, the use of a simplified Taguchi technique in novel Dioscorea alata stems fiber processing is proposed to allow for simultaneous evaluation of control parameters such as treatment type, harvest condition, gauge length and chemical treatment temperature to determine the optimal conditions for fiber tensile properties. These fibers were extracted from the stem by means of water retting method before chemical treatment. The tensile properties were determined as per ASTM D3822/D3822M-14. Non-destructive examinations were employed to look into the chemical make-up, thermal, crystalline and morphological characteristics of the fibers. The test results showed an optimum tensile strength of 151 MPa and tensile modulus of 5709.5 MPa. Density was 0.4 g/cm3 while cellulose, lignin, moisture, hemicellulose and ash contents were 13.1 %, 10.3 %, 9.7 %, 5.0 % and 8.2 % respectively. The treated fibers were thermally stable till 320 °C. The properties of Dioscorea alata stem fiber (DASF) were found to be promising when compared to existing natural fibers, making it a viable candidate for composite material reinforcement.

Effect of Hybridization, manufacturing methods and factors influencing natural fibers reinforced composites and its commercial applications – A review

Excessive deployment of petroleum resources results very high accumulation of CO2 in the atmosphere along with other associated consequences like global warming, disturbances in the Ozone Layer etc. In this scenario, protection of environment and sustaining the ecological balance by taking suitable measures become need of the present time. It becomes most desirable to utilize renewable and sustainable resources as much as possible to save the environment. Application of plant derived resources in the preparation of polymer composites is one good alternative for successful utilization of renewable resources and a sustainable environment. This leads the scientists and researchers to concentrate more on the application of natural fibers and other plant based resources for the preparation and development of natural fiber polymer composite, wood plastics composite etc. Large number of plant resources is employed for such development and also for commercial production of different environment friendly composites. This review focuses on various factors influencing the mechanical properties of natural fibers reinforced composites (NFRC’s). Effect of hybridization and manufacturing methods of NFRC’s also addressed.

Experimental Investigation on the Mechanical Properties of Natural Fiber Reinforced Concrete

Recently, addition of various natural fibers to high strength concrete has aroused great interest in the field of building materials. This is because natural fibers are much cheaper and locally available, as compare to synthetic fibers. Keeping in view, this current research conducted mainly focuses on the static properties of hybridized (sisal/coir), sisal and coir fiber-reinforced concrete. Two types of natural fibers sisal and coir were used in the experiment with different lengths of 10, 20 and 30 mm and various natural fiber concentrations of 0.5%, 1.0%, and 1.5% by mass of cement, to investigate the static properties of sisal fiber reinforced concrete (SFRC), coir fiber reinforced concrete (CFRC) and hybrid fiber reinforced concrete (HFRC). The results indicate that HFRC has increased the compressive strength up to 35.98% with the length of 20 mm and with 0.5% concentration, while the CFRC and SFRC with the length of 10 mm and with 1% concentration have increased the compressive strength up to 33.94% and 24.86%, respectively. On another hand, the split tensile strength was increased by HFRC with the length of 20 mm and with 1% concentration, CFRC with the length of 10 mm and with 1.5% concentration, and SFRC with the length of 30 mm and with 1% concentration have increased up to 25.48%, 24.56% and 11.80%, respectively, while the HFRC with the length of 20 mm and with 0.5% concentration has increased the compressive strength of concrete but has decreased the split tensile strength up to 2.28% compared to PC. Overall, using the HFRC with the length of 20 mm and with 1% concentration provide the maximum output in terms of split tensile strength.

Evaluation of conductivity and mechanical properties of natural fiber reinforced soy‐melamine formaldehyde based green composite

AbstractThis article presents the preparation and characterization of jute‐based green composite using various concentrations of melamine formaldehyde modified soy resin. Highest tensile strength of 62.1 MPa was obtained for 50 wt.% melamine formaldehyde modified soy resin‐based jute‐composite due to formation of synergic bonding between melamine formaldehyde, soy protein and cellulose of jute. Other tensile and flexural properties were also enhanced with increase in melamine formaldehyde content from 0 to 50 wt.%. Storage modulus of developed composite (50 wt.%) was enhanced by 8.48 times as compared to that of soy‐jute composite (0 wt.% melamine formaldehyde). Water absorption of optimum composite was reduced by 45% than that of the normal jute‐soy composite. With increase in melamine formaldehyde content (0–100 wt.%), surface electrical insulation and fire retardance properties of composite were also enhanced drastically. Weight loss data and scanning electron microscopic images of degraded composites after 180 days under soil burial condition revealed that developed composites are bio‐degradable in nature and can replace non‐degradable plastic in different industrial sectors like railway coaches, packaging sector, decorative commodity material, and so on.

Effect of ultraviolet radiation and water spraying on the mechanical properties of multi‐walled carbon nanotubes reinforced natural fiber and hybrid composites

AbstractThe main objective of this study was to investigate the effect of aging by ultraviolet radiation and water spray on the mechanical properties of natural fiber and hybrid composites. Pure jute, hybrid jute/glass, and glass fiber‐reinforced composites were fabricated. All these types of composites were further modified with 0.6 wt% of multi‐walled carbon nanotubes (MWCNTs) and their mechanical behavior was compared to the unmodified specimens. Tensile and flexural tests were used to measure the mechanical properties of unaged (control) and aged specimens. A scanning electron microscopy analysis was used to examine the fracture surfaces of the specimens tested. It was found that the aging process affected the mechanical properties of the composites studied in different ways. For jute and jute + MWCNT composites the properties decreased with increased exposure time. The hybrid jute/glass composites (unmodified and MWCNT modified) were less affected by aging and showed an insignificant change in tensile strength. The hybrid + MWCNT composites, showed an increase of approx. 7% in Young's modulus (1000 h) and 9% (500 h) and 17%, (1000 h) in flexural modulus when compared to the unexposed specimens. The MWCNTs had a positive effect on the mechanical properties of the glass + MWCNT aged samples.

Development and investigation of the mechanical properties of natural fiber reinforced polymer composite

Natural fibers have an important role to play. Because of their constructive properties, reinforced polymer composite materials are increasing at a faster rate in the field of engineering and commercial application. Natural fibers have advantages over synthetic reinforcement composite. This experimentation was to investigate the mechanical behaviors such as tensile and flexural strength of natural fiber composite consist of jute and banana fiber as reinforcement and epoxy resin as matrix for two different fiber orientation (0°, 90°). From the investigation, it was examined that 0° orientation fiber had higher tensile and flexural strength compared to 90° orientation fiber. Also, it could be drawn from the experimentation that mechanical properties of composite material depend on orientation of fiber and the direction of application of load.

Influence of surface modifications of Castor oil fibre on mechanical properties of fibre reinforced Epoxy composites

ABSTRACT Castor oil fibre was identified as a new reinforcement for polymer-based composites and can be used in automobile applications. However, the mechanical properties of natural fibres were considerably less when compared with synthetic fibres and can be improved by the surface modification techniques via chemical treatment. In the present work, unidirectional castor oil fibre-reinforced epoxy composites were prepared by hand lay-up process. The tensile, flexural and impact strength properties of composites at 40% volume fractions were tested as per ASTM standards. Mercerised (NaOH) castor-oil fibre-reinforced composite exhibited 28%, 39%, 34%, 25%, 115% of the increment in tensile strength, tensile modulus, flexural strength, flexural modulus, impact strength respectively over untreated composites, the permanganate (KMnO4)-treated castor oil fibre-reinforced composites showed 9%, 35%, 15%, 15%, 85%, respectively. Thus, NaOH chemical treatment gives better results than KMnO4 chemical treatments due to the removal of unwanted material from surface effectively in NaOH treatments. The SEM results showed that the treated composites have a strong interfacial bond regarding untreated composites. Mechanical properties of the composites were predicted by using regression, ANN-single hidden layer, ANN-multi hidden layer models and confirmatory test results shows the reliability of predicted models. The ANN-multi hidden layer model giving the better results.

Investigation on Recent Research of Mechanical Properties of Natural Fiber Reinforced Composites (NFRP) Materials

Renewability, recyclability and biodegradable contents are similar to glass fibers in natural fiber reinforced polymer composites (NFRP) which have definite mechanical properties. The interface of polymer matrix and natural fibers results the composites to achieve superior properties of products. Researchers have extended their product designs and production techniques by using renewable materials such as jute fiber, cotton fiber, silk fiber, etc. which are enormous and used in the manufacture of durable industrial goods of high-end quality. This paper reviews the current developments and the brief findings needed in literature, concentrating on the mechanical properties and applications of NFRP.

WITHDRAWN: A review on mechanical properties of natural fiber reinforced polymer (NFRP) composites

Abstract One of those innovations that led to their substantial growth in the field of engineering is natural fiber hybrid composites. Natural fiber-reinforced composites are used to replace synthetic fibers manufactured from boron, fiber glass, carbon fiber, etc. in a variety of application areas. Natural fibers, particularly in domestic uses in plants, animals, and regenerated material, are de-grading and durable compared to synthesized fibers. Strengthened polymers are common in natural fibers, such as cotton, sisal, coir, jute, flax, hemp, banana, flax, and more. Recently, for their excellent mechanical, chemical, and physical features many sectors have been added, such as vehicles, aerospace, marine, and buildings. Because of these properties, natural fibers have recently become an alternative approach for fiber-reinforced compo-sites for researchers and scientists. This paper explores the mechanical characteristics of natural fiber reinforced hybrid composites.

A Review on Banana Fiber and Its Properties

There are many types of natural fiber including hemp, flax, jute, wood fiber, rice husks, straw wheat, oats, bagasse, barley, grass reeds, banana fiber, oil palm empty fruit bunch, coir, sisal, cotton, kenaf, ramie, water pennywort, paper-mulberry, kapok, abaca, pineapple leaf fiber. The production of banana in India is 13.5 million tons per annual. Banana forming generates more quantity of biomass which goes as waste. The above ground parts like pseudo-stem and peduncle are the major source of fiber. Banana fiber used as a raw material in industry for production of papers, tea bags, currency and reinforced as a polymer composite. Natural fiber is used as an alternative resource to synthetic fibers as well as reinforcement for polymer composite materials and the manufacturing is inexpensive, renewable and environment friendly. Natural fibers have low cost, low density and low durability as compare to synthetic fibers but with the help of fiber treatments, mechanical properties of natural fibers are improved. In this paper, banana fibers are compared through their applications, use and properties and thus it is concluded that the banana fibers provide better chemical composition and properties.

A Review on Mechanical Properties of Natural Fibre Reinforced Polymer Composites under Various Strain Rates

With the lightning speed of technological evolution, the demand for high performance yet sustainable natural fibres reinforced polymer composites (NFPCs) are rising. Especially a mechanically competent NFPCs under various loading conditions are growing day by day. However, the polymers mechanical properties are strain-rate dependent due to their viscoelastic nature. Especially for natural fibre reinforced polymer composites (NFPCs) which the involvement of filler has caused rather complex failure mechanisms under different strain rates. Moreover, some uneven micro-sized natural fibres such as bagasse, coir and wood were found often resulting in micro-cracks and voids formation in composites. This paper provides an overview of recent research on the mechanical properties of NFPCs under various loading conditions-different form (tensile, compression, bending) and different strain rates. The literature on characterisation techniques toward different strain rates, composite failure behaviours and current challenges are summarised which have led to the notion of future study trend. The strength of NFPCs is generally found grow proportionally with the strain rate up to a certain degree depending on the fibre-matrix stress-transfer efficiency. The failure modes such as embrittlement and fibre-matrix debonding were often encountered at higher strain rates. The natural filler properties, amount, sizes and polymer matrix types are found to be few key factors affecting the performances of composites under various strain rates whereby optimally adjust these factors could maximise the fibre-matrix stress-transfer efficiency and led to performance increases under various loading strain rates.

Effect of graphene nanoplatelet filling on mechanical properties of natural fiber reinforced polymer composites

Abstract In this study, the mechanical properties of plain woven jute-epoxy composite materials were investigated after filling graphene nanoplatelets (GNPs) in different proportions. The time dependent changes in the viscosity and temperature of unfilled epoxy resin, with 0.5, 1 and 2 wt.-% graphene nanoplatelets filled epoxy resins were observed. Woven jute reinforced unfilled, 0.5 wt.-% GNPs filled and 1 wt.-% GNPs filled epoxy composite plates were produced by using vacuum assisted resin transfer molding (VARTM) at the same waiting and processing times. Specimens were prepared and subjected to tensile and flexural tests according to ASTM D 3039 and ASTM D 790 standards, respectively. Images were taken and evaluated with a scanning electron microscope (SEM) in areas where tensile damage occurred. It was observed that the gap amount between the fiber and the matrix increased and the interface adhesion decreased as the fill amount increased in the composites produced. The testing results indicated that the tensile and flexural properties of composites decreased at 0.5 wt.-% and 1 wt.-% during the GNPs loading as compared to unfilled composites.

Mechanical properties of natural fiber reinforced polylactide composites: A review

Nowadays, there is an augmented concern for the development of not only well-designed but also fully sustainable materials. The extraction of renewable resources and disposal processes that would not harm our eco-system is associated with material sustainability. In this respect, biodegradable polymers and natural fibers are suitable alternatives to many non-degradable composites which one lightweight. Many researchers are trying to fabricate composites by adding these two through various means and characterizing their mechanical properties to find the suitability of these for different applications. The present article reviews the literature on the fabrication of polylactide composite reinforced with natural fibers, both of which are biodegradable fully; further, the article reviews the methods used by the researcher for characterizing mechanical properties of these composites.