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The acrylic acid treated rattan fiber reinforced epoxy (RF/Epoxy) composite has been fabricated by taking various weight percentages (5, 10, 15, 20, and 25 wt%) of fibers using hand layup followed by compression molding technique. The optimum fiber loading has been determined by regression analysis and it is found that 18 wt% of rattan fiber gives maximum tensile strength. The interaction of rattan fiber with epoxy matrix has been studied by Fourier transform infrared spectroscopy and X-ray diffraction. Scanning electron microscope (SEM) has been used to study the morphology of chemically modified rattan fiber and RF/Epoxy composite. The mechanical, thermal, and dynamic mechanical thermal properties of 18 wt% RF/Epoxy composite have been studied as per ASTM standards. From the results, it is observed that RF/Epoxy composite gives best properties at optimum (18 wt %) fiber loading. The maximum tensile strength and flexural strength of the composite are found to be 47.5 and 121 MPa, respectively, which is better in comparison to other natural fiber composites used for manufacturing different automobile body parts. Hence, it can be concluded that 18 wt% RF/Epoxy composite can be considered as a potential candidate for automotive body parts. [ABSTRACT FROM AUTHOR]

The aim of the effort is to estimate the effect of jute and bamboo fibers with silica fume (SF) of different proportions on mechanical properties of concrete. Cube, cylinder and prism specimens are tested to determine the compressive, split tensile and flexural strength at 14 and 28 days of curing. To verify the experimental findings, further Artificial Neural Network (ANN) analysis is conducted. The study employs neural network (NN), such as the Neural Network-Leven Berg–Marquardt and the Neural Network Gradient Descent. In this investigation, feed-ahead lower back promulgation neural networks were employed. The NN predicted values are validated with actual values and the variation is found to be within 10% only. The predicted ANN results are compared with existing Response Surface Methodology model. Under compressive, split tensile and flexural load, the broken surface is examined at a smaller-scale level with a scanning electron microscope (SEM). The experimental results show that concrete with 0.5% bamboo fibers and 0.5% jute fibers with 10% SF had higher influence on the mechanical properties of concrete. When comparing ANN results, the suggested ANN model showed high level of accuracy in estimating the mechanical properties of natural-fiber-reinforced concrete. SEM examination displayed the failure pattern of concrete and fibers. [ABSTRACT FROM AUTHOR]

This study is intended to improve the methodology to calculate the tensile properties of natural coconut fiber and increasing confidence in the use of sustainable natural fibers as reinforcing in composites used for different components in the naval industry. Coconut fiber is an agribusiness by-product that has been shown to have the potential for the development of new materials. The morphology of different species of coconut fiber was studied, and their mechanical tensile properties were determined. The coconut fibers were tested under direct tension in a universal testing machine, and the cross-sectional area of the fibers was calculated using images obtained in an optical microscope and a scanning electron microscope. The study assessed the incidence of key factors to determine coconut fiber mechanical tensile properties including different area measuring methods and the percentage of lumens present through an image analysis software called ImageJ. The results indicate that coconut fiber has a round-shaped cross-section, and the percentage of lumens is between 15% and 27%. Therefore, the effective area is reduced increasing the fiber's ultimate resistance to tension. [ABSTRACT FROM AUTHOR]

The mechanical behavior of banana fiber (BA) reinforced polymer composites filled with fly ash (FA) is analyzed in this present investigation. Polyester matrix is used to produce composites with 30% of banana fiber volume and fly ash with three separate volume fractions (1%, 3% & 5%). The failure mechanisms were identified through a scanning electron microscope using the fractured surfaces of the specimen after mechanical testing. The addition of 3% vol of fly ash results in an increase in the tensile, flexural, and impact strength of 46.3%, 24%, and 88.4% when compared with the banana fiber composites without fly ash (BAP). 5% vol of higher fly ash addition indicates a drop in the tensile, flexural, and impact properties of approximately 31.4%, 9.38%, and 30.61% when compared to 3% vol of fly ash added composites, respectively. Owing to weak interfacial bonding caused by the agglomeration of fillers, the higher filler loading results in subdued mechanical properties. With the help of SEM fractography, the parameters, including poor interfacial adhesion, defective surfaces, and fractures, were described. [ABSTRACT FROM AUTHOR]

In the present research, our aim is to study effects of alfa fiber content, alkali, maleic anhydride grafted polypropylene (MAPP), and the combined treatment (alkali and MAPP) on the tensile and flexural behavior of alfa fiber-reinforced polypropylene (PP) composites. These composites were produced using a single-screw extruder followed by an injection molding process. Both fibers and composites were characterized using optical and SEM microscope in order to evaluate the interfacial adhesion between the fibers and the matrix. From the main results, the tensile modulus and flexural strength of 30% untreated Alfa fiber/PP composites were found to increase significantly compared to those of PP. Meanwhile, there is no significant increase in terms of the tensile strength and the flexural modulus. Moreover, the composites with a combined treatment have shown significant effect on the tensile and flexural properties compared to untreated composites and the treated ones. The SEM observation of the morphology of alkali treated fibers exhibited an increase in the surface roughness because the removal of impurities. In addition, SEM photos of the fractured surface of composites reveal the improvement of the fibers and PP matrix interface quality by treatments, in particular the combined treatment. [ABSTRACT FROM AUTHOR]

The main goal of this study is to assess the mechanical, physical and morphological properties of bundle fibers extracted from curaua leaves and pullout testing in cementitious matrix. The mechanical properties of the fibers were analyzed in mechanical testing of four fiber lengths (10, 20, 30 and 40 mm) to observe the influence of the length of the variable's tensile strength, Young's modulus and Weibull modulus. Pullout testing was measured frictional and maximal force. Fibers physical properties were assessed by means of the multipycnometer method. Morphological analyses were conducted through optical and scanning electron microscopes. The results showed that the fiber length does not interfere with the tensile strength (507–638 MPa) and Weilbull modulus (8–12). However, it influences the Young's modulus (19–39 GPa). Curaua bundles present a higher resistance to rupture and Young's modulus than other plant fibers species and it seems to be related to the distribution of faults along the beam. The fibers morphological characterization showed a rough and irregular surface with some impurities which are associated with the surface of the fibrous bundle and low adherence (0,26–0,47 N) with cementitious matrix in pullout testing. [ABSTRACT FROM AUTHOR]

The study deals with the mechanical and thermal characterization of novel composite consisting of vetiver grass fiber (Chrysopogon zizanioides) (VF) and red mud (RM) as reinforcement in epoxy resin. Five types of composites were fabricated using hand lay-up technique by varying the weight percentage (wt%) of vetiver grass and red mud. Various mechanical properties like tensile strength, impact strength, and flexural strength of the said composites were evaluated and discussed. The thermal properties in terms of thermo gravimetric analysis (TGA) were evaluated whereas the chemical composition characteristics were analyzed using FTIR and XRD spectroscopy. The fractured surfaces of the tested specimens were studied using a scanning electron microscope. From the results, it was observed that properties of polymer composites were improved by hybridization with vetiver grass fibers and red mud. The improved mechanical properties of fiber-reinforced composites were noticed in increment of wt% of red mud. Highest tensile strength of 51.78 MPa, flexural strength of 35.92 MPa and impact strength of 29 KJ/m2 was obtained for C5 composite which contains highest wt% of red mud. TGA shows better resistance to thermal degradation for the composites containing higher percentage of red mud. Looking at the results it can be concluded that the developed composites in this work can be an efficient alternative for building and automotive application which requires high strength and thermal stability. [ABSTRACT FROM AUTHOR]

In the present study, a new composite based on epoxy resin reinforced with Lygeum spartum L. fibers was prepared using compression molding technique. Chemical, mechanical as well as morphological analyses were carried out on the Epoxy/Lygeum spartum composite (Epoxy/LS) using ATR-FTIR, tensile and flexural tests, and SEM spectroscopy. An increase in the intensity of several bands associated to the main complements of vegetable fibers (cellulose, hemicellulose, and lignin) was showan using ATR-FTIR analysis. An improvement in the mechanical properties of this new material was observed, with respect to the neat epoxy resin. This was of the order of 117 % and 85 % for tensile and flexural modulus respectively, and of the order of 40 % and 9 % for tensile and flexural strength, correspondingly. A good fiber-matrix adhesion was also observed from tensile fracture surface of composite using scanning electron microscope (SEM). All the obtained results demonstrated the effectiveness of the Lygeum spartum fibers as reinforcement of composite materials. [ABSTRACT FROM AUTHOR]

The present work aims to investigate the effect of nanofiller, lead oxide on the mechanical, thermal, and water intake behavior of luffa fiber-reinforced epoxy polymer matrix composites. Filler material PbO of 20 nm was added in different weight proportions along with luffa fiber to the matrix and the compression molding technique was used for the fabrication of the composite laminates. Tensile, flexural, and impact properties were studied on the prepared samples. The influence of lead oxide on glass transient temperature (Tg) and the curing of epoxy were also studied using the Differential scanning calorimeter. The optimum mechanical and thermal properties were observed on the addition of 1.25 wt. % of nanofiller. The morphological images show various defects like interfacial behavior, fiber pulls outs, voids, and internal cracks, and these were examined using a scanning electron microscope. Hence the present investigation showed that the addition of nanofiller could enhance the mechanical strength of the natural fiber composite. Further, it enhanced the moisture resistance and thus could find potential structural and packaging applications. [ABSTRACT FROM AUTHOR]

Hybrid laminates made using natural fibers have been finding applications in diverse fields such as automotive parts, building structures and sports goods. These laminates incorporate the benefits of the reinforcements used in constructions. The present work deals with the fabrication of hybrid laminate comprising of the natural fibers areca and kenaf in varying stacking sequences through the hand layup method. Epoxy resin (LY556) and hardener (HY951) are mixed in the ratio of 10:1 to prepare the matrix material. Six different hybrid laminates having five layers of areca and kenaf in different stacking sequences are produced. Two more laminates having either kenaf or areca in all the five layers and are produced to act as reference laminate. The prepared laminates are cut as per ASTM standards and subjected to tensile, compressive, flexural, impact and hardness tests in order to identify the properties of the fabricated laminates. The result shows that composite made with kenaf fiber as skin material and areca as core materials exhibit better tensile, flexural and hardness properties. Likewise, composites with outer layers of areca and core layers of kenaf fibers have high compressive and impact strength. The fractured surfaces after the mechanical tests are investigated through the Scanning Electron Microscope (SEM). [ABSTRACT FROM AUTHOR]

Bacterial cellulose is one of the widely discussed biomaterials due to its unique physical, mechanical and chemical characteristics. In this research, bacterial cellulosic film (BCF) was developed using Acetobacter xylinum strain in green tea as a source of carbon under static culture conditions. The developed BCF was evaluated for their morphological properties using a scanning electron microscope and the approximate fiber diameter noted as 38–40 nm. The purity of the cellulose evaluated through an X-ray diffraction method identified that the developed cellulose is Iα rich – triclinic type with 89.61% of crystallinity. The thermal behavior of the BCF was evaluated using TGA and DSC. The results indicated that the major weight loss occurred from 250 to 500°C. The glass transition temperature (Tg) of the developed BCF was very high and it was 165°C. Concerning the mechanical properties, the BCF had lower tensile strength (13.82 Kgf/Cm2), Elongation (10.13 mm) and air (19.72 cm3/cm2/sec) and water vapor permeability value (151 g/m2/day) than the woven cotton fabric. However, the water absorbency (0.7 s) and water holding capacity (320%) are superior to the cotton fabric. The contact angle of the BCF was noted around 28.53°, which is an indication of the higher hydrophilic nature of the BCF. These results provide an insight into the potential applications of bacterial cellulosic material in the apparel and textile sector. [ABSTRACT FROM AUTHOR]

Applicability of natural fiber-reinforced composites in automobile, aerospace like sectors has been increasing as more number of research works is concentrating on natural fibers owing to their eco-friendly nature. Biodegradability of natural fibers is main advantage of them over artificial fibers. Natural fiber-reinforced composite possesses good thermal and mechanical properties besides other requirements. For this reason, investigation of one such natural fiber-reinforced composites has been the focus of the present study. In the present work, composites made up of abutilon indicum fiber reinforced with epoxy have been prepared. Mechanical, morphological, thermal, and spectroscopic studies on the test specimens prepared using the above composites were carried out to evaluate their respective strengths. Also, the effect of alkali treatment (NaOH) for the fibers was studied and evaluated. Scanning electron microscope results indicated that the composite made up of alkali-treated fibers possessed better mechanical properties. Using differential thermal analysis–thermogravimetric analysis apparatus thermal behavior of the composites and using Fourier transform infrared spectroscopic studies, the presence of function groups like C–O, C–H was determined. Thus, characterization of abutilon indicum fiber-reinforced epoxy composites has been carried and properties are evaluated for their applicability to automotive, aerospace similar industries. [ABSTRACT FROM AUTHOR]

Usage of composites with natural fiber reinforcement is drastically increasing in recent times because of their low density, biodegradable nature, and low cost. However, natural fibers have certain core problems such as poor adhesion between the fiber and matrix and a relatively high degree of moisture absorption. Alkaline treatment of natural fibers is aimed at improving the adhesive strength so that effective stress transferability takes place in the composite. In the present work, Cordia-Dichotoma fibers were treated with sodium hydroxide (NaOH) and composites were prepared with different weight ratios of these fibers reinforced with epoxy. The prepared composites were tested for their tensile and flexural strengths (mechanical properties). Besides, for a comprehensive material characterization, IR spectroscopy (FT-IR), scanning electron microscope, and thermogravimetric analysis were carried out. This work investigates the influence of aforementioned NaOH treatment on thermal, mechanical, and morphological properties of the composite material. [ABSTRACT FROM AUTHOR]