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Polymer composite materials were prepared using kaolinite nanoclay as reinforcement in different weight fractions (3, 5 and 7) %, and blends of epoxy and polymethyl methacrylate (PMMA) as matrices. The current work aims to prepare a composite material with good thermal and acoustic insulation, besides improved mechanical properties, and the investigation of the effect of this nano additive on the compatibility between the two constituents of the blend, and how this compatibility might be beneficial to the performance of the prepared composite. The blend with an optimum mixing ratio (OMR) was chosen via impact test results; thus, the (80:20) percentage of epoxy and PMMA was chosen. The reinforced specimens showed an improvement in mechanical (impact and flexural) properties besides sound insulation and thermal conductivity, with the specimen reinforced with 7% nanoclay having the highest impact strength (97*10−3) KJ/m2 and the highest thermal conductivity value of (0.34) W/m.°C, with a sound intensity value 95.6 decibels at frequency 10,000 Hz. The scanning electron microscope images showed two separate phases in the unreinforced blend. In comparison, the 7% reinforced specimen showed a rough interface between the two polymer phases, suggesting a positive effect of nanoclay addition on compatibility. The differential scanning calorimeter showed two distinct glass transition temperatures for both reinforced and neat specimens, which belong to the glass transitions of both constituents (epoxy and PMMA). The main difference is the lower temperature gradient accompanied with the (nanoclay/blend) composite than the neat one. Although the blend remained immiscible, nanoclay had contributed to the compatibility and improved mechanical properties. [ABSTRACT FROM AUTHOR]

In this work, a comparative assessment of the mechanical properties of chopped glass-carbon-aramid fiber reinforced polypropylene (PP) composites was carried out. Reinforcement and matrix materials were mixed with the extrusion method, and then composite materials were produced in the form of plates with the press molding technique. The composites' tensile, 3-point bending, and drop weight tests were carried out and the surface morphology of the fractured surfaces was examined by Scanning Electron Microscope (SEM). The tests' results indicate that the mechanical properties increase significantly in the presence of fiber. On the other hand, it is observed that the effect in percentage decreases as the fiber content increases. Moreover, It was observed that some of the fiber materials were pulled out from the matrix as a result of stress. ANOVA analysis using S/N values, and F-Test were performed to observe the effectiveness of each test factor (fiber type, and fiber additive content) on the test results. Finally, an optimization study was carried out to obtain the mathematical expression by fitting the experimental data. [ABSTRACT FROM AUTHOR]

The main objective of this research was to study the influence of an enzymatic treatment process of date palm fibers on their chemical and morphological properties as well as the physical and mechanical characteristics of composites filled with raw and treated fibers. To this end, three extraction approaches were considered (a combination of xylanase and pectinase enzymes, xylanase enzymes followed by a pectinase one and pectinase enzyme followed by xylanase). Chemical and morphological analyses were performed on raw and treated fibers. The tensile test of the manufactured composites was achieved, using extrusion and injection molding process. These composites were also subjected to water absorption tests. The results showed that non-cellulosic components decreased after enzymatic treatments while the cellulose content increased significantly. The scanning electron microscope morphological analyses showed that the extraction with the combination of these enzymes is very effective as a fibrillation phenomenon. Composites with high rigidity were observed in the case of enzymatically treated fibers. These composites reveal a better moisture resistance compared to the untreated fibers. Graphical Abstract [ABSTRACT FROM AUTHOR]

In recent times, polymer composites have played an epochal role in transforming material science. Some of their properties such as toughness, strength, flexibility and rigidity have helped them supplant conventional materials such as iron, steel, and aluminium on several occasions. Apart from this, they are light in weight and more cost-efficient, which make them a viable alternative. They have found their application in several fields such as automobile industry, aerospace industry, construction and pipeline industry. Owing to its excellent impact strength, tensile and hardness, natural fibres serve as an excellent replacement. Natural fibres are an environmental friendly, biodegradable and are readily available. The present investigation uses a new fibre for manufacturing the eco-friendly composite material. Mechanical properties such as tensile strength, shear stress, flexural rigidity, impact strength and hardness of a coconut fibre-reinforced polymer composite material are evaluated as per respective ASTM standards. A surface analysis of the material using a scanning electron microscope is also performed. The results are categorized and tabulated accordingly. The values obtained appear to fall in line with the experimental data and hence can be espoused as an alternative material especially in the automotive sector. [ABSTRACT FROM AUTHOR]

In this study, bamboo and glass fibers were successfully added into bisphenol A–aniline-based benzoxazine resin by hot pressing method. The effect of water absorption on the mechanical properties of the neat benzoxazine and its composites was studied. The composites prepared in this study has been proved to exhibit better water resistance than some conventional natural fiber/polymer composites due to good hydrophobicity of the benzoxazine matrix. From the mechanical tests, the tensile performance of both neat benzoxazine and the composites degraded seriously after prolonged immersion in water. However, neat benzoxazine and the composites maintained relatively higher residual flexural properties (residual mechanical properties refer to the ratio of strength and modulus of the saturated samples to that of the nonaged samples) after 20 days of water immersion. The effect of water molecules on the fracture surface morphologies of the composites was studied using a scanning electron microscope (SEM). The SEM images showed that the interfacial bonding between fibers and the matrix degraded seriously due to the attack of water. [ABSTRACT FROM AUTHOR]

Hybrid matrices (epoxidized of ethylene–propylene–diene monomer (eEPDM) -g- aminopropyltriethoxysilane (APTES)/hydroxyl terminated polydimethylsiloxane (HTPDMS)/polyurethane (PU)) were developed based on eEPDM with 3-APTES coupling agent and varying weight percentages (0.75, 1.50, 2.25, and 3.00 wt%) of PU prepolymer as coreactant using 7.5 wt% of HTPDMS as chain extender using suitable experimental conditions. The formation of hybrid matrices and their structure were characterized by Fourier transform infrared (FTIR). The thermal and morphological properties of the hybrid matrices were analyzed using differential scanning calorimetry and scanning electron microscope, respectively. Mechanical properties (tensile strength, elongation at break (%), Young's modulus, and hardness) were characterized as per ASTM standards. Data resulted from mechanical studies, it was noticed that the incorporation of 3-APTES, HTPDMS, and PU into eEPDM has improved the elongation at break (%) and lowered the values of tensile strength, Young's modulus, and hardness according to the percentage concentration. Morphological studies indicate the presence of heterogeneous morphology. Data obtained from different studies, it suggested that the hybrid matrices developed in the present work can be used as cable insulates for high-performance industrial and engineering applications. [ABSTRACT FROM AUTHOR]

The present research venture focuses on utilization of food and agricultural waste Citrus limetta (musambi) peel by using it as a filler material to develop novel epoxy (EP) composites. Experimental investigation has been performed to analyse the influence of C limetta (musambi) peel particles (CLPP) on mechanical properties (tensile, flexural and impact strength) of the developed composites. Different loadings by weight percentages (0, 5, 10 and 15 wt%) of filler have been used to explain the variation in mechanical properties. Along with effect of different filler percentages, failure characteristics of the prepared samples have also been studied. The results indicate that higher CLPP content in EP matrix has a detrimental effect on mechanical properties of manufactured biocomposites. Thermal characterization was performed to analyse the degradation behaviour and the onset temperature. Morphological analysis of the fractured surfaces was also conducted with the help of a scanning electron microscope. The current experimental investigation has revealed that CLPP can be used as a potential filler for manufacturing biocomposites with applications in general purpose interior fitments in addition to various non-structural components. [ABSTRACT FROM AUTHOR]

Natural fibres used as reinforcing materials in polymer matrix composites provide positive environmental benefits with respect to ultimate disposability and best utilization of raw materials. Banana fibre is waste from banana trunks or stems which are abundant in many places in the world. To benefit the environment, agricultural industry as well as other industries, there is a need for development of new usage of agricultural waste. Natural fabric based green composites were prepared by hand lay-up technique with natural woven banana fabric (WBF) and Isophthalic acid based unsaturated polyester resin (UPR) as matrix. The mechanical, dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA) and morphological properties of these green composites were investigated. The WBF were treated with 6% aqueous solution of NaOH. Untreated and NaOH treated fabric surfaces were analyzed by using Fourier transform infrared spectroscopy (FT-IR) and Scanning electron microscope (SEM) studies was carried out to evaluate fabric/matrix interactions. Thermogravimetric analysis of the samples indicated better thermal properties of the alkali treated fibres. The improved fabric--matrix interaction is evident from the enhanced tensile and flexural properties. Reduction in water absorption of alkali treated WBF/UPR composite was observed. The results proved that appropriate alkali treatment of banana fabric improved interfacial adhesion, and in turn mechanical and water absorption properties of the green composite made in this study. [ABSTRACT FROM AUTHOR]