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Although asbestos fiber is used for autobrake pad production due to its heat resistance capacity, it is associated with a challenge of health risk (cancerogenic in nature). This health risk associated with asbestos-based autobrake pads has presented polymeric materials as a better candidate for the application due to their eco-friendliness, lightweight, chemical inertness, easy of processing, etc. However, polymers are associated with low wear and low mechanical properties, which are vital properties for autobrake pads. Therefore, this study developed EP nanocomposites reinforced with a low content of carbon nanotubes (CNTs) and eggshell (ES) attached cow bone (CB) particles denoted as (ES@CB) as agro-waste/sustainable materials for the manufacturing of autobrake pads. The hybrid ternary nanocomposites were developed via solution mixing and casting. Scanning electron microscope (SEM) revealed the 1-D structure of the CNTs, and relatively spherical shapes of ES and CB particles, and microstructures of the developed nanocomposites. The nanocomposite showed a low coefficient of friction and a reduction in wear rate in the range of 1.14 × 10−4 mm3/Nm for pure EP to 5.45 × 10−6 mm3/Nm for EP/0.4wt%CNTs-10wt%ES@CB nanocomposite, while the elastic modulus and hardness increased from 1.84 GPa and 128.64 MPa for pure EP to 4.41 GPa and 252.88 MPa for EP/0.2wt%CNTs-20wt%ES@CB nanocomposite, respectively. The comparison of the wear response of the developed nanocomposites with the current asbestos-based brake pads show that the developed epoxy nanocomposites from agro-waste materials are potential option for the manufacturing of autobrake pads, which will ensure sustainability, health risk-free, and environmentally friendly. [ABSTRACT FROM AUTHOR]

The biggest problem facing the automotive industry today is limited natural resources and environmental protection. Therefore, it is very important to conduct and carry out research and mapping of alternative materials that can reduce the use of non-renewable materials. The aim of this research is to determine the effect of variations in the volume of teak wood powder on the impact strength of composites with a polyester polymer matrix and identify fracture patterns. This research uses an experimental design combined with one-way statistical analysis of variance to test the research hypothesis. The results showed that there were significant differences in impact strength between the variations of the three specimens tested. Specimens with variations in volume fraction of 20%:80% for teak wood powder and polyester resin have the highest impact strength, while specimens with variations in volume fraction of 30%:70% for teak wood powder and polyester resin have the lowest impact strength. Apart from that, examination of the microscopic structure of the fracture patterns shows differences in fracture patterns between specimens. Specimens with variations in volume fraction of 0% (100% polyester resin) show a brittle fracture mechanism, while specimens of 10%:90%, 20%:80%, 30%:70% for teak wood powder and polyester resin show that the fracture pattern that appears is a combination of fragility and fibular fracture which is also called a fibrous fracture.

Currently, there has been a shift away from synthetic materials towards natural fibers. Composite materials are now being created by using fillers, which are essential for maintaining mechanical strength. Hence, the amalgamation of organic fibers and additives serves as a superior substitute for artificial substances in lightweight applications. The study selects Ramie (Boehmeria nivea) fibers as the reinforcement phase and polyester as the matrix material. Subsequently, five composite laminates are produced by incorporating alumina filler with varying weight fractions into each sample in order to assess the impact of the composite on the antibacterial conductivity, mechanical characteristics, and thermal stability of the ramie fibre (RF) composite. Among the RF composite samples, Sample A (120 g RF, 25 g alumina filler, and 120 g epoxy matrix), which consisted of 25 g of alumina particles, had the most superior mechanical qualities, such as tensile strength (34.89 MPa), flexural strength (39.25 MPa), and impact strength (0.023 J/mm2). The antibacterial findings of ramie raw fibre indicate that the presence of ramie cellulose stimulates bacterial proliferation, and the energy dispersive study verifies that the alumina filler is significantly affected in this RF composite. The source of the material's failure under mechanical loading of the composite was established using scanning electron microscopy (SEM). [ABSTRACT FROM AUTHOR]

Sebagai upaya pemanfaatan potensi limbah cangkang kerang hijau (Perna Viridis L.), cangkang kerang hijau dapat dimanfaatkan sebagai penguat (filler) pada komposit dengan matriks polyester. Tujuan dari penelitian ini yaitu untuk menganalisis sifat mekanis komposit matriks polyester dengan filler cangkang kerang hijau. Pada penelitian ini digunakan beberapa bahan matriks berupa Resin Polyester dan Methyl Ethyl Keton Peroxide (MEKP) yang berfungsi sebagai katalis. Sampel yang telah dibuat selanjutnya akan dilakukan karakterisasi uji tarik menggunakan mesin UTM (Universal Tensile Machine). Pengujian tarik terhadap komposit ini dilakukan untuk mengetahui kekuatan tarik matriks polimer dengan penguat cangkang kerang hijau. Penelitian kali ini menggunakan partikel cangkang kerang hijau berukuran 100 mesh, kemudian variasi fraksi volume filler yang digunakan yaitu 0%, 10%, 20% dan 30%. Metode hand lay up yang digunakan dalam pembuatan material komposit ini. Diperoleh data hasil penelitian dengan nilai kekuatan tarik tertinggi terdapat pada variasi fraksi volume filler 10% dengan nilai sebesar 18,49 MPa.

This work aims to investigate the potential of nonwovens made from untreated (U) and alkaline/bleaching treated (T) palm, wool, and polyester fibers as reinforcing materials in polyester matrix for automotive interior applications. Four needle-punched nonwovens were developed and used with and without chloropropyltriethoxysilane (CPTS) treatment as polyester matrix fillers. Eight composite panels were made using the resin transfer molding machine process and compared to the matrix panel in terms of physical, mechanical, thermal, and climate resistance. The produced composite materials have smooth surfaces and provide consumers with four different aesthetically pleasing finishes. The physical results reveal that the UPalm/Wool and UPalm/Polyester nonwovens lower matrix density from 1223.3 Kg/m3 to 1022.3 and 1040.7 Kg/m3, respectively. The SEM images show that palm fibers are more adherent to the matrix after being treated with an alkaline/bleaching solution. This adhesion is also improved after nonwovens are treated with the CPTS precursor. The composite reinforced with CPTS-treated TPalm/Polyester nonwoven has the highest tensile strength and modulus (72.1 MPa and 3.76 GPa), which are 127% and 36% greater than those of the polyester matrix, respectively. The matrix's flexural strength and modulus are also enhanced by 148% and 59%, respectively, after reinforcing with CPTS-treated TPalm/Polyester nonwoven. The use of TPalm/Wool and TPalm/Polyester nonwovens as polyester matrix fillers reduces their thermal conductivity from 0.125 W/(m.K) to 0.081 and 0.095 W/(m.K), respectively. Moreover, the climate aging results indicate that composites reinforced with CPTS-treated nonwovens are more stable to climate, implying their applicability and durability in automotive interior applications. [ABSTRACT FROM AUTHOR]

This research work makes use of a novel polyalthia longifolia leaf mid-rib fibers as a potential reinforcement for polymer composites. The fibers were subjected to sodium hydroxide treatments for different duration, and its effect on the tensile strength of the polyalthia fibers was examined. 6 h treatment was found to be optimum with a maximum tensile strength of 134 MPa. Scanning electron microscopy of the fiber surface revealed surface impurities, waxy granules and breakage of fibrils as some of the prominent features for variation in tensile strength. Fourier transform infrared spectra of all varieties of fibers supported function group modifications. Polyester-based composites were fabricated with 6 h treated fibers, and their mechanical properties were determined. Maximum values of tensile, flexural and impact strength obtained were 43MPa, 35MPa and 12 kJ/m2 respectively. Fiber breakage, fiber pull-out and de-bonding were some of the fracture mechanisms observed through scanning electron micrographs of the polyalthia longifolia composites.

The effects of fiber orientation and volume fraction on the mechanical and thermal properties of laminated jute reinforced polyester composite are investigated. The composite sheets of thickness 4.0 mm are fabricated by hand lay-up method using three laminated stacks of jute fibers and four different orientations (0°/90°/0°, 90°/0°/90°, 45°/0°/-45° and −45°/90°/45°). For each fiber orientation, two-volume fractions of 20% and 30% are used. The mechanical properties such as tensile, flexural, impact strength, modulus of toughness and elasticity, and hardness of the fabricated composites are evaluated by testing as per ASTM standard. The thermal conductivity of the composite sheets is determined by Lee’s method. It is found that the mechanical strength, surface hardness and thermal conductivity of the laminated jute reinforced polyester composite are increased with fiber volume fraction and varied with fiber orientation. The tensile strength, energy absorption and load-bearing capacity are found the highest for 45°/0°/-45°, second-highest for 0°/90°/0° and the lowest for −45°/90°/45° fiber orientation. The flexural strength is found the highest for 0°/90°/0° and the second-highest for 45°/0°/-45° fiber orientation. The method and procedure of this research work can be used to fabricating moderate size jute reinforced polyester composites with elevated in-plane strength in both longitudinal and lateral directions.

This research work makes use of a novel polyalthia longifolia leaf mid-rib fibers as a potential reinforcement for polymer composites. The fibers were subjected to sodium hydroxide treatments for different duration, and its effect on the tensile strength of the polyalthia fibers was examined. 6 h treatment was found to be optimum with a maximum tensile strength of 134 MPa. Scanning electron microscopy of the fiber surface revealed surface impurities, waxy granules and breakage of fibrils as some of the prominent features for variation in tensile strength. Fourier transform infrared spectra of all varieties of fibers supported function group modifications. Polyester-based composites were fabricated with 6 h treated fibers, and their mechanical properties were determined. Maximum values of tensile, flexural and impact strength obtained were 43MPa, 35MPa and 12 kJ/m2 respectively. Fiber breakage, fiber pull-out and de-bonding were some of the fracture mechanisms observed through scanning electron micrographs of the polyalthia longifolia composites. [ABSTRACT FROM AUTHOR]

The effects of fiber orientation and volume fraction on the mechanical and thermal properties of laminated jute reinforced polyester composite are investigated. The composite sheets of thickness 4.0 mm are fabricated by hand lay-up method using three laminated stacks of jute fibers and four different orientations (0°/90°/0°, 90°/0°/90°, 45°/0°/-45° and −45°/90°/45°). For each fiber orientation, two-volume fractions of 20% and 30% are used. The mechanical properties such as tensile, flexural, impact strength, modulus of toughness and elasticity, and hardness of the fabricated composites are evaluated by testing as per ASTM standard. The thermal conductivity of the composite sheets is determined by Lee's method. It is found that the mechanical strength, surface hardness and thermal conductivity of the laminated jute reinforced polyester composite are increased with fiber volume fraction and varied with fiber orientation. The tensile strength, energy absorption and load-bearing capacity are found the highest for 45°/0°/-45°, second-highest for 0°/90°/0° and the lowest for −45°/90°/45° fiber orientation. The flexural strength is found the highest for 0°/90°/0° and the second-highest for 45°/0°/-45° fiber orientation. The method and procedure of this research work can be used to fabricating moderate size jute reinforced polyester composites with elevated in-plane strength in both longitudinal and lateral directions. [ABSTRACT FROM AUTHOR]

In this paper, the three-point bend flexural testing of composites reinforced with woven glass fibers and unidirectional glass fibers are presented. The experimental study was done according the ASTM standard. A finite element simulation was done in order to investigate the mechanical behavior of woven glass fibers and unidirectional glass fibers reinforced polymer composites. The finite element results were compared with experimental data, thus obtaining very close values. The composites plates were obtained through hand layup technology. [ABSTRACT FROM AUTHOR]

The paper presents the manufacturing technology for a material obtained from glass fiber waste, quartz sand, and polyester binder, used for ornamental building plates. The composite has a cover surface that ensures protection of the material from environment attacks and a structural material that can be subjected to chemical degradation. The mechanical properties of the obtained material were experimentally investigated through compressive mechanical tests. To observe the material’s behavior in contact with external agents (rain or acid rain, due to environmental pollution), analyses were performed in laboratory conditions. An investigation on the effects of chemical attack substances was conducted. SEM and macroscopic analyses were performed, and the surface roughness was determined for each sample area. The obtained results were statistically analyzed and showed that there is no significant difference between the surface roughness for treated and untreated samples. Furthermore, the surfaces were analyzed by X-ray diffraction and mineralogical optical microscopy in polarized light with crossed nicols. It was observed that rainwater does not affect the plate structure even if the plates are used in high-pollution environments. The material is suitable for exterior building walls from the point of view of chemical attack and resistance.

In the present research, synthesis and characterization of hybrid bamboo/glass fiber reinforced polyester (PE) matrix-based composites through compression moulding technique was fabricated and characterization is done. Seven different combinations of composite plates were prepared with the fiber alignment of 30o and 60 o in a plain weaved mat form. Experimental results show that when hybrid fibers combined with polyester matrix, mechanical properties such as tensile strength, flexural strength, impact strength, hardness and water absorption tests of the matrix increases the superior specific strength and modulus but have a lower failure strain compared to other combinations and then pure bamboo or pure glass fiber possess decrease in strength compared to hybrid combinations. Thermal and Morphological investigation of the pure bamboo or pure glass fiber and hybrid fiber fiber-reinforced polyester composites have also been carried out. The results found show that application of these fibers as probable reinforcing materials in bio-based polymer composites. [ABSTRACT FROM AUTHOR]

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A relatively unknown natural fiber extracted from the leaves of the fique plant, native of the South American Andes, has recently shown potential as reinforcement of polymer composites for engineering applications. Preliminary investigations indicated a promising substitute for synthetic fibers, competing with other well-known natural fibers. The fabric made from fique fibers have not yet been investigated as possible composite reinforcement. Therefore, in the present work a more thorough characterization of fique fabric as a reinforcement of composites with a polyester matrix was performed. Thermal mechanical properties of fique fabric composites were determined by dynamic mechanical analysis (DMA). The ballistic performance of plain woven fique fabric-reinforced polyester matrix composites was investigated as a second layer in a multilayered armor system (MAS). The results revealed a sensible improvement in thermal dynamic mechanical behavior. Both viscoelastic stiffness and glass transition temperature were increased with the amount of incorporated fique fabric. In terms of ballistic results, the fique fabric composites present a performance similar to that of the much stronger Kevlar™ as an MAS second layer with the same thickness. A cost analysis indicated that armor vests with fique fabric composites as an MAS second layer would be 13 times less expensive than a similar creation made with Kevlar™. [ABSTRACT FROM AUTHOR]

The aim of this work is to provide some economic value to the agricultural residues by using them as reinforcements in polymer composites. Sugarcane bagasse and coconut shell powder are termed as reinforcements along with unsaturated polyester matrix. Sugarcane fibers are surface treated with sodium hydroxide and hydrochloric acid for better surface adhesion. Effect of water absorption of untreated and surface treated sugarcane fiber polyester composites filled with coconut shell filler were evaluated on tensile specimens. It was observed that untreated sugarcane fiber composites absorb less percentage of water when compared to NaOH treated and HCl treated sugarcane fiber composites. Tensile properties of sugarcane fiber composites are decreased with increase in water absorption. Morphological study through scanning electron microscope reveals that interfacial bonding between fiber and matrix was found excellent NaOH treated sugarcane fiber compared to untreated and HCl treated sugarcane fiber. [ABSTRACT FROM AUTHOR]

A relatively unknown natural fiber extracted from the leaves of the fique plant, native of the South American Andes, has recently shown potential as reinforcement of polymer composites for engineering applications. Preliminary investigations indicated a promising substitute for synthetic fibers, competing with other well-known natural fibers. The fabric made from fique fibers have not yet been investigated as possible composite reinforcement. Therefore, in the present work a more thorough characterization of fique fabric as a reinforcement of composites with a polyester matrix was performed. Thermal mechanical properties of fique fabric composites were determined by dynamic mechanical analysis (DMA). The ballistic performance of plain woven fique fabric-reinforced polyester matrix composites was investigated as a second layer in a multilayered armor system (MAS). The results revealed a sensible improvement in thermal dynamic mechanical behavior. Both viscoelastic stiffness and glass transition temperature were increased with the amount of incorporated fique fabric. In terms of ballistic results, the fique fabric composites present a performance similar to that of the much stronger KevlarTM as an MAS second layer with the same thickness. A cost analysis indicated that armor vests with fique fabric composites as an MAS second layer would be 13 times less expensive than a similar creation made with Kevlar™.

Composites were prepared with 13, 23 30 and 40 % fiber and evaluated the mechanical performance in tensile, flexural and impact. The mechanical properties of these composites were also evaluated function of time at 110 °C thermal exposure. Caroa fibers were characterized by techniques such as thermal gravimetric analysis (TGA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). It was found that the best mechanical properties were achieved for composites containing 23 to 30 % fiber. The incorporation of 23 % fiber caroa increased both the modulus of elasticity in the tensile test as the flexural strength and impact, the composite with 30 % fiber caroa showed higher tensile strength. The results show that the tensile and flexural strength of the composite decreased with time of thermal exposure. The thermal aging at 110 °C caused a decrease in tensile properties of the composites. [ABSTRACT FROM AUTHOR]

Technological regimes of introducing carbon nanotubes (CNTs) into a polyester matrix composite are considered, and the properties of the obtained composition are studied. It is established that agglomerates that cannot be broken up by a mechanical stirring are formed at the moment of CNT wetting with the polyester binder. The use of an ultrasound disperser makes it possible to get rid of agglomerates but leads to enhanced porosity, with additional technological operations being necessary for reducing the latter. [ABSTRACT FROM AUTHOR]

In this work, naturally woven coconut sheath, a new type of reinforcement was used. Composite Laminates were prepared in a compression molding press. Tensile, flexural and impact tests were conducted as per ASTM standards, and results were compared with the glass fibre composite. Fractured specimens were analyzed with the help of scanning electron microscope images. Enhancements in mechanical properties were found with the new reinforcement. And the coconut sheath was found to be a suitable material that can reduce the utilization of non-decomposed glass fibres for polymer composite reinforcements. [ABSTRACT FROM PUBLISHER]

The effect of silane treatments on the water absorption properties of mercerized bamboo matting reinforced polyester composites were investigated. Treatments using γ-Aminopropyltriethoxy silane, 3-trimethoxysilylpropyl methacrylate, Vinyltris(2-methoxyethoxy)silane, Bis[3-(triethoxysilyl)propyl] tetrasulfide, 3-aminopropyltrimethoxy silane and n-Octyltrimethoxy silane were carried out to improve the water resistant property of the bamboo fibers. Water absorption in the composites was studied by long-term immersion and 2 h boiling in distilled water. The process of absorption of water was found to follow the kinetics and mechanism described by Fick's theory. Alkali treatment results in reduction of water absorption from 51% to 35%. Further reduction is observed with silane treatment. Water absorption varies between 19% and 44%, the minimum being for aminopropyl triethoxy silane-treated composites. [ABSTRACT FROM AUTHOR]

The paper presents the manufacturing technology for a material obtained from glass fiber waste, quartz sand, and polyester binder, used for ornamental building plates. The composite has a cover surface that ensures protection of the material from environment attacks and a structural material that can be subjected to chemical degradation. The mechanical properties of the obtained material were experimentally investigated through compressive mechanical tests. To observe the material's behavior in contact with external agents (rain or acid rain, due to environmental pollution), analyses were performed in laboratory conditions. An investigation on the effects of chemical attack substances was conducted. SEM and macroscopic analyses were performed, and the surface roughness was determined for each sample area. The obtained results were statistically analyzed and showed that there is no significant difference between the surface roughness for treated and untreated samples. Furthermore, the surfaces were analyzed by X-ray diffraction and mineralogical optical microscopy in polarized light with crossed nicols. It was observed that rainwater does not affect the plate structure even if the plates are used in high-pollution environments. The material is suitable for exterior building walls from the point of view of chemical attack and resistance. [ABSTRACT FROM AUTHOR]

The dynamic compression behavior of the adhesively bonded composite glass/polyester composite joints at high strain rates was reported earlier by the authors. From this study, it was a question of investigating the dynamic behavior of each component of the adhesively composite joints (adhesive; polymer matrix and the laminate) for a better physical understanding of large deformations in composite assemblies. The results were interpreted here in the context of an experimental investigation of the high-strain-rate compressive behavior of the polyester resin matrix using the Split Hopkinson Pressure Bars (SHPB). The dynamic tests had been performed on the resin samples at similar dynamic conditions that the adhesively composite joints to demonstrate strain rate effects of the resin, as well as to study its own failure process. It was concluded that the dynamic parameters of the resin matrix depended strongly on strain rate due to the visco-plastic effect and the failure modes of the polymer. Based on the experimental results, empirical formulations including the strain-rate effects were developed, for modeling more faithfully the dynamic behavior of composites structures under the impact. [ABSTRACT FROM AUTHOR]