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In this study, an attempt is made to check whether a hybrid composite made up of both synthetic and natural fibers (Carbon and Cordia Dichotoma respectively) can be made bio-degradable, at least to some extent, without much compromising on the mechanical properties. Hybrid composites were prepared by reinforcing alkali treated Cordia dichotoma and carbon fibers into epoxy resin using hand lay-up method. By varying the number of layers of fibers in the composite specimen and fixing 20% fiber weight for all composites, nine distinct combinations of specimens were prepared. The maximum tensile strength of 386.68 MPa, flexural strength of 647.08 MPa, and impact energy of 4.82 J were obtained for composites produced with pure carbon fiber, whereas hybrid composite exhibit tensile strength of 367.76 MPa, flexural strength of 646.41MPa and impact energy of 4.74 J. The interfacial bonding between the fibers and matrix of tested specimens was studied using a scanning electron microscope (SEM), as well as the arrangement of fibers within the matrix for the manufactured composite. Thermogravimetric analysis (TGA) was used to investigate thermal stability, and it was found that it was thermally stable up to 415°C. 9. Crystallinity value increases from 20% carbon fiber to 20% alkali fiber. [ABSTRACT FROM AUTHOR]

Natural fiber reinforced composites are attracting the attention of industries toward a sustainable and environment-friendly material for the future demands. The main drawback pertaining to the use of natural fiber composites lies in its inferior strength in comparison to its counterpart synthetic fibers. This research focuses on improving the fracture toughness of woven jute fabric mat with different orientations (0°, 30° and 45°) in epoxy resin by incorporating fillers and tested in universal tensile testing machine. Silicon carbide (SiC) particles of three sizes 26 µm, 54 µm and 72 µm were incorporated in the matrix in different weight ratios (5%, 10% and 15%). The fracture toughness of the jute/epoxy composites increases with the increase in the amount of SiC particles up to 10% addition and then it shows decreasing trend with further addition. The fracture toughness values show upward trend when the fiber orientation changed from 0° to 45°. Fractography of the tested specimen captured by scanning electron microscope which reveals the fracture of fibers and micro cracks in the epoxy matrix due to the applied load. Analysis of variance (ANOVA) is also conducted for predicting the most influencing parameters on the fracture toughness. [ABSTRACT FROM AUTHOR]

The natural fiber extracted from water hyacinth waste could be used for making natural fiber polymer composites. The main intent of this manuscript is to develop polymer composite materials reinforced by aquatic wastewater hyacinth natural fibers having varying lengths. The water hyacinth fibers were extracted using a mechanical drum extractor followed by a drying process at a speed of 320 rpm. Mechanical testing of the composites was conducted as per the relevant ASTM standard and subsequently, thermo gravimetric analysis was also conducted to assess the thermal characteristics of the composites. Fourier-transform infrared spectroscopy (FTIR) and X-Ray diffraction (×RD) techniques were employed to characterize the elemental and microstructural properties of the composites. A 20 mm fiber length with a 30% fiber content resulted in the best mechanical properties. Fractured surfaces from the composite samples are evaluated by using a scanning electron microscope (SEM). Brittle fracture, fiber pulled out, fiber clusters are identified as the general failure characteristics of the composites. This study demonstrated that the hyacinth fiber reinforced epoxy resin composite could be useful for developing particleboard products, as well as other lightweight products. [ABSTRACT FROM AUTHOR]

For sustainable thermal insulations, vegetable fibers/stems are widely used, which have very dispersed material properties even within a variety. The examination of the fibers' porosity in the conventional way provided reference values in this study, but it can be problematic for cellulose-based fibers. This study examines the porosity of two straw types (barley and wheat) and searches for faster and easier tests; it reveals the inaccuracies that can occur in different methods. The image processing method is applied on records of intact cross-sections made by scanning electron microscope; the essential circumstances to reach the intact cross-section are also discussed in the paper. Stitched cross-sections, made from overlapping records using the same magnification, are supplemented by detailed images with higher magnification. On the fused/detailed images, the entire region of the crosssections was segmented. Each pore was automatically analyzed (area, diameter, perimeter) to determine porosity; the result was compared to the conventional method. Comparing the entire and the detailed cross-sectional image gives information about the importance of magnification in the analysis. The presented method is suitable for porosity measurement but needs some modification in sample preparation and image capturing. Both the conventional and image processing methods provide the same results in ratios between the two straw types but different absolute values. [ABSTRACT FROM AUTHOR]

Decorticated ramie fiber (Variety R-1449) was degummed using different systems, namely, individual alkali, mix alkali, enzyme, mix enzyme, and peracetic acid to the optimal level of residual gum content. Further, the optimal degummed samples of various systems have been characterized through IR analysis, DSC thermographs, scanning electron microscopes, tensile properties etc. The chemical constituents of degummed samples of various systems at optimal level along with untreated decorticated ramie fiber have been determined and compared. Study suggests the use of new eco-friendly peracetic acid is best degumming method for decorticated ramie followed by synergetic effect of alkalis. [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]

Electrospun biocompatible fiber mats were made with Poly Vinyl Alcohol (PVA) using a biocompatible solvent Dimethylsulfoxide (DMSO), because of its compatibility. We have also used the herb "Thespesia populnea" to produce herbal doped electrospun mats. Five samples are produced by varying the percentages of PVA and herbal and the parameters in electrospinning machine. Among those samples, fiber is formed properly when PVA and herbal are taken in the ratio of 5% and 10%, respectively and when Distance, Flow rate, Voltage are set as 15 cm, 0.05 mL/h and 14 kV, respectively. The PVA fiber formation is investigated using a scanning electron microscope (SEM). Fourier Transform Infrared Spectroscopy (FTIR) has been done to confirm the presence of functional group of the herbal and PVA in the mat. Antibacterial testing was done for the samples, and the zone of inhibition was found to be 8–12 mm. Drug release test revealed that the drug from the electrospun mat was better around 70%. In vitro cytotoxicity test was done, and the result obtained was negative since a large amount of DMSO was used for dissolving the herbal. Hence it can be controlled by reducing the usage of DMSO. [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]

Zingiber officinale (known as ginger), a natural flowering plant of Zingiberaceae family, was taken to investigate its possible utilization in a textile material. Zingiber officinale fibers (ZOFs) were obtained from the plant root. The cellulose, hemicellulose, and lignin contents of ZOFs were determined. Elemental analysis of ZOFs was carried out with energy dispersive X-ray analysis (EDX) instrument. Surface morphology of fibers was investigated with a scanning electron microscope (SEM) instrument. The chemical functional groups of ZOFs were confirmed with Fourier transform-infrared spectroscopy (FT-IR). The crystalline structure of ZOFs was analyzed with X-ray diffraction (XRD), and then the crystallinity index was calculated as 78.81%. In addition to this, mechanical properties of ZOFs were investigated with Shimadzu Ag-X machine. The EDX and FT-IR results show that ZOFs have cellulosic structure. Furthermore, it was obtained that ZOFs have rough surface structure and the thickness is approximately 155 µm. The physical properties of ZOFs are substantial enough for its usage as a textile fiber. [ABSTRACT FROM AUTHOR]

In the present scenario, the searching for novel plant fibers able to be used as reinforcement of polymer composites is highly appreciable. This study deals with extraction and characterization of Eleusine indica grass fibers extracted from its stem by manual retting process. From this study, it was found that the Eleusine indica has higher cellulose of 61.3 wt% content, density of 1143 kg/m3, average tensile strength and Young's modulus equal to 22 MPa and 10.75 GPa, respectively. From the XRD studies, it was noted that the Crystallinity Index (CI) of Eleusine indica was 45%. The surface morphology of Eleusine indica grass was examined using a Scanning Electron Microscope (SEM) and Chemical functional group were confirmed by Fourier transform infrared spectroscopy (FT-IR). The thermal stability of EIF was evaluated using TG and DTG curves from Thermogravimetric (TG) analysis. The characterization results confirmed that Eleusine indica grass could be used for the production of sustainable fiber-reinforced polymer composites. [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]