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This research investigates the mechanical characteristics of a novel hybrid composite material, which combines bio-epoxy reinforced with sisal fiber and integrated with fly ash nano-fillers. The study focuses on exploiting the environmentally friendly attributes of natural fiber composites and reducing reliance on synthetic materials. In this study, sisal fiber serves as the reinforcement, and a bio-epoxy matrix is utilized to create the composite. To further enhance its properties, fly ash, a byproduct of coal-fired power plants, is incorporated as a nano-filler. The experimental findings reveal significant improvements in the mechanical properties of the composite due to the inclusion of fly ash nano-fillers. The tensile strength shows a notable enhancement of up to 6.3%, flexural strength experiences an impressive increase of 68%, impact strength demonstrates a remarkable boost of 28%, and scratch hardness elevates by 17% which were all achieved at 20% fiber weight fraction and 5% fly ash weight fraction. The considerable potential of this hybrid sisal fiber reinforced bio-epoxy composite, integrated with fly ash nano-fillers, as an eco-friendly alternative to traditional synthetic composites is evident from these results. Such enhancements make the composite suitable for a wide range of engineering applications, including the manufacturing of automotive components, construction materials, and consumer goods. By adopting this bio-composite, industries can actively contribute to sustainable practices while maintaining optimal performance in their products. This research offers valuable insights into a promising solution for eco-conscious engineering applications, with both quantitative and qualitative evidence demonstrating the achievement of superior mechanical properties in this innovative hybrid material. [ABSTRACT FROM AUTHOR]

Hybrid composites with synthetic and natural fibers are a good choice in the field of composites, as they combine the good mechanical performance of synthetic fibers with the advantages of natural fibers. In this work, polymeric hybrid composites associating glass fiber and natural fibers were developed. Three hybrid composites were developed: sisal/glass, coir/glass and Luffa/glass. The composites are five-layer laminate, three layers of E-glass interspersed with two layers of natural fibers that can be sisal, coir, or Luffa sponge (Luffa Cylindrica). In addition to hybrid composites, a five-layer fiberglass composite was also manufactured. The composites were manufactured by compression molding technique using orthophthalic polyester resin as matrix. Tensile and flexural tests were performed to characterize the composites. Considering the three hybrid composites, the best behavior was observed for the sisal/glass composite, being a potential replacement for fiberglass. The order of performance was the same in the tensile and flexural tests, sisal/glass, coir/glass, and luffa/glass, in this order. In the specimen's fracture analysis, for both tests, it was observed that the fracture was quite located with no damage in regions far from the fracture. This behavior indicates good adhesion between the layers of natural and synthetic fibers, despite the discrepancy of their properties. [ABSTRACT FROM AUTHOR]

Demand for natural fibers reinforced composites is growing as an alternative to synthetic fiber reinforced plastic composites. However, poor compatibility between natural fiber and matrix has limited its development. Therefore, it is necessary to improve their interfacial adhesion to improve the comprehensive properties of composites. In this work, sisal fibers were subjected to an alkali/polyvinyl alcohol coating treatment by an ultrasonic impregnation method, and the sisal/high-density polyethylene composite was prepared by a twin-screw extruder. The Fourier transform infrared spectroscopy was used to characterize the modification effect of sisal fiber. The surface morphology of sisal fiber and the interfacial morphology of sisal/high-density polyethylene composites were observed. The mechanical properties and water absorption of sisal/ high-density polyethylene composites were also studied. The results show that alkali/polyvinyl alcohol coating compound treatment can effectively improve the interfacial adhesion between sisal fiber and high-density polyethylene, improve the mechanical properties of composite, and reduce water absorption. Alkali/polyvinyl alcohol coating compound treatment is a very environment-friendly, cost-effective fiber modification method when compared with traditional modification methods. It is helpful for the development and application of natural fibers reinforced composites. [ABSTRACT FROM AUTHOR]

An effective method was adopted to improve the thermo-mechanical properties of the epoxy composite by functionalization of the sisal fiber. Initially, a neat sisal fiber was acetylated with molar solution of acidic mixture (0.5:1 of HNO3:H2SO4) that removed the content of lignin and hemicellulose and increased the crystallinity of the sisal fiber. The acetylated sisal (a-sisal) fiber was further treated with 3-aminpropyltriethoxy silane to graft the silanol moieties on sisal fiber. The functionalization of the sisal fiber with 3-aminpropyltriethoxy silane exhibits the strong interaction with epoxy, resulting in homogenous dispersion of the sisal fiber in epoxy. The composite possesses great enhancement in thermal and mechanical properties. The tensile strength in functionalized sisal epoxy composite (CP-f-Sisal) was significantly enhanced up to 23% in comparison to non-functionalized sisal epoxy composite (CP-n-Sisal) by adding 15 wt.% of the sisal fiber. In addition, the functionalized sisal epoxy composite (CP-f-sisal) shows better thermal stability as compared to non-functionalized sisal epoxy composite (CP-n-sisal). Similar results are attributed by investigating the kinetics of thermal stability parameters that include activation energy and integral procedure decomposition temperature. [ABSTRACT FROM AUTHOR]

Currently, there is a tendency to develop materials that have an increasingly specific purpose for a particular application and the composites can be part of these types of materials. In addition, there is a search for replacement of synthetic fibers with natural ones, because of concerns about the environment. Hybridization of glass fiber composites with sisal fibers can result in improved performance by combining the benefits of each fiber with various applications. Many studies are developed on these types of composites, sisal/glass hybrids, varying certain parameters, such as matrix, orientation of fibers, treatment of fibers, stacking of layers, composition of elements, method of manufacture, among others, characterizing the various types of properties. The present work organizes the researches on the hybrid composites of sisal/glass, in chronological order, highlighting the specifications and parameters used and the main results obtained. [ABSTRACT FROM AUTHOR]

In this article, a detailed systematic methodology to fabricate and characterize the diverse properties of soy protein and sisal fiber reinforced green composites has been presented. After fabrication by hand lay-up and solution casting method, these composites with varying sisal fiber weight percentages (0, 3, 4, 5, 6, 7 and 10) were put to various characterization tests. The surfaces of sisal fiber were treated with sodium hydroxide to enhance its interfacial bonding properties. The fabricated samples were examined on the basis of microstructural tests that included the scanning electron microscopy; followed by the mechanical (tensile) and physical (water absorption) tests. Finally, the thermal tests were performed that involved the thermogravimetric analysis, differential thermal analysis and dynamic mechanical analysis tests. The phytagel modified soy protein-based composite with 5 wt.% of sisal fiber content was confirmed to be the best of all compositions under this scrutiny, which was authenticated by the micro-structural and mechanical tests. To further enhance the mechanical, physical and thermal properties of fabricated composites, chitosan coating was applied on them. [ABSTRACT FROM AUTHOR]

The incorporation of sisal fiber as reinforcement materials for polymers will be advantageous if it is synthesized and manufactured perfectly. In this study, surface modification using polymeric diphenylmethane di-isocyanate and gamma-aminopropyltriethoxysilane was applied for further amelioration of polypropylene–sisal bonding. Surface morphology, thermomechanical properties, thermal stability, and chemical bonding were investigated using scanning electron microscopy, dynamic mechanical analysis, thermogravimetric analysis, and Fourier transform infrared spectroscopy, respectively. A number of mathematical models were studied for predicting the effect of untreated and modified sisal fiber loadings on the mechanical properties of biocomposites. Polymeric diphenylmethane di-isocyanate showed a significant improvement on the thermal and mechanical properties of polypropylene biocomposites. Fourier transform infrared spectroscopy analysis of polypropylene–sisal biocomposite showed the formation of urethane group at 3333 cm−1 in the presence of polymeric diphenylmethane di-isocyanate. Glass transition temperature of polypropylene–sisal was slightly increased to 6.8°C by chemical modification with polymeric diphenylmethane di-isocyanate. Yield strength of polypropylene–sisal (30 wt%) was enhanced by more than 50% with polymeric diphenylmethane di-isocyanate chemical treatment. Halpin–Tsai and Nielsen theoretical mathematical models showed a good agreement with experimental results of polypropylene–untreated sisal and polypropylene–treated sisal, respectively. [ABSTRACT FROM AUTHOR]

In the current research enterprise, behavior of novel bio-composites incorporating Aloe Vera fibers in biopolymer matrix (polylactic acid) has been experimentally examined in comparison to Sisal fiber reinforced bio-composites. These bio-composites were melt blended using single screw extruder prior to injection molding. The effect of fiber weight fraction (10–20–30%) and fiber surface modification on mechanical behavior of developed bio-composites was investigated. Alkaline treatment using sodium hydroxide concentration of 5% was used for fiber surface modification. Both alkali treated and raw fibers were characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis and scanning electron microscope. Thermal stability of the fibers improved after alkaline treatment. The mechanical characteristics of developed bio-composites exhibited an improvement with increasing fiber concentration. Alkaline treatment of fibers further improved the tensile, flexural and compressive properties of developed bio-composites, while their impact properties declined compared to raw fiber reinforced bio-composites. Moreover, from the results, it is evident that the characteristics of Aloe Vera fiber reinforced bio-composites are comparable to Sisal fiber reinforced bio-composites and the developed bio-composites have the potential to be used in various automotive, furniture and architectural applications. [ABSTRACT FROM AUTHOR]

Low-polymerization degree polylactide was grafted onto sisal fiber surface on the basis of the principle of lactide coordinative ring-opening polymerization. The effects of surface treatment on the thermal properties of sisal fibers were investigated. Sisal fiber reinforced polylactide composites were prepared by melt blending, and the impacts of surface treatment and annealing treatment on thermal properties and crystallization of the composites were studied. Results demonstrated that thermal stability of composites decreased with the addition of sisal fibers, among which lactide-grafted sisal fiber reinforced polylactide (PLA/SF-g-LA) composites decreased the most. The crystallinity of composites increased with the addition of sisal fibers compared with neat polylactide. Transcrystallinity appeared in PLA around the sisal fibers with the addition of sisal fibers. The glass transition temperature, crystallinity and crystal perfection of neat polylactide and composites were improved with annealing treatment. [ABSTRACT FROM AUTHOR]

Application of natural fibers has attracted a great deal of attention among the composite research community in the past couple of decades. In this study, sisal fiber was utilized in fabrication of syntactic foam to improve the mechanical properties. Four sets of samples with different volume fractions of sisal fibers (0%, 1.5%, 2.5%, and 3.5%) were prepared. Viscoelastic properties of the samples were characterized with dynamic mechanical analysis. Storage and loss moduli, complex viscosity, and damping factor (tan δ) of syntactic foam samples were recorded. Dynamic mechanical analysis results showed improvement in storage and loss moduli in glassy region (30℃) up to 12% and 300%, respectively. In rubbery region (150℃), the storage modulus of sisal fiber syntactic foam was three orders of magnitude higher than plain ones. Decrease in the tan δ peak also indicated improved interfacial bonding by addition and increase in the content of sisal fibers. All these improvements in viscoelastic properties were achieved without any significant change in the density of syntactic foam. [ABSTRACT FROM PUBLISHER]

In this study, properties of natural rubber (NR) were enhanced by adding sisal fiber, which is a tropical plant in Thailand. Sisal fiber/natural rubber composites were prepared by the incorporation of sisal fiber at various loadings into natural rubber. Natural rubber grafted with maleic anhydride (NR-g-MA) prepared in house and epoxidized natural rubber (ENR50) were used to enhance the compatibility between sisal fiber and natural rubber. With increasing fiber loading, tear strength and hardness of natural rubber composites increased while their scorch time, cure time, tensile strength, and elongation at break decreased. Moreover, interfacial adhesion between sisal fiber and natural rubber was enhanced with the addition of NR-g-MA and ENR50. In comparison, NR-g-MA provided more effective improvement in mechanical properties of natural rubber composites than ENR50. For NR-g-MA compatibilized natural rubber composite at fiber loading of 10 phr, its tensile strength, modulus at 100% strain, modulus at 300% strain, tear strength, and hardness were increased 43, 44, 53, 42, and 13%, respectively, comparing with that of uncompatibilized natural rubber composite. [ABSTRACT FROM PUBLISHER]

The effect of fiber twist on the tensile properties of single sisal fibers was investigated by single fiber tensile test. Four kinds of sisal yarns with four different levels of twist were made and the mechanical properties were investigated on both unimpregnated and resin-impregnated sisal yarns. A critical fiber twist level for unimpregnated sisal yarns was found beyond which the tensile properties started to decrease with the increasing of the level of fiber twist. However, for resin-impregnated sisal yarns, both tensile strength and modulus decreased with the increasing of the fiber twist level. In addition, the effect of fiber twist on both the tensile and flexural properties of unidirectional sisal yarn reinforced composites was studied. It was shown that lower twist level led to higher mechanical properties of its reinforced composites. Compared with the experimental results, Rao’s model proved to accurately calculate the Young’s modulus of fiber yarns with different levels of twist. Thus, the Young’s modulus of sisal yarn reinforced composites could be predicted by the rule of mixtures hereafter. [ABSTRACT FROM PUBLISHER]

Sisal fibers were pretreated by alkali and maleic anhydride, and then mixed with polypropylene to fabricate sisal fiber-reinforced composites by a self-made vane extruder based on elongational flow field. Maleic anhydride-grafted polypropylene was used as compatilizer to increase the fiber/matrix interactions. The influence of treatment on the fibers structure, the damage to fibers in processing, interfaces of composites and the mechanical properties of composites were investigated. It was observed that the surface of treated fibers was improved obviously compared with that of untreated fibers, which was believed to increase the adhesion between the fibers and matrix. However, the treated fibers were more likely to be damaged during processing. In comparison to unmodified system, the incorporation of treated fibers could significantly enhance the mechanical properties of composites, especially adding the compatilizer of maleic anhydride-grafted polypropylene. The flexural and impact strengths were maximum for the sisal fiber/polypropylene and maleic anhydride-grafted polypropylene composites, and its tensile strength was also improved significantly. The major contribution of this change should be that the morphology of fibers could be well preserved in elongational flow field, which based on the vane extruder showed a good application in fiber-reinforced composites. [ABSTRACT FROM AUTHOR]

The incorporation of fibers as reinforcements in polymer composites has increased due to their renewability, low cost and biodegradability. In this study, sisal fibers were added to a polymer matrix of thermoplastic starch and polycaprolactone, both biodegradable polymers. Sisal fibers (5% and 10%) were extruded in a twin-screw extruder with thermoplastic starch/polycaprolactone (80:20 wt). Films were produced with a single extruder and analyzed by field emission gun scanning electron microscopy, mechanical tests, thermogravimetric analysis and differential scanning calorimetry. The morphology of the composites with 10% sisal fiber content presented an interface of fibers at the surface of the matrix, indicating poor adhesion, lower initial temperatures of thermal degradation, and decreased polycaprolactone crystallinity due to the decrease in lamellar thickness and the increase in crystalline disorder. The results were affected mainly by the lack of adhesion at the interface between the matrix and fibers. The interfacial shear strength between sisal and the matrix may be improved by chemical modification of the fiber surface. [ABSTRACT FROM PUBLISHER]

Natural fabric-based thermoset composites are generally lower in strength performance compared to hybrid composites. However, they have the advantages of design flexibility, cost effectiveness, lack of health-hazard problems and recycling possibilities. Hybridization with some amounts of synthetic fibers makes these natural fabric composites more suitable for technical applications such as automotive interior parts. Kapok fabric is one of the important lignocellulosic plant fabrics and has been used as a reinforcement for hybridizing with glass and sisal fabrics in polyester matrix. This study focused on the performance of impact properties of kapok/ glass and kapok/sisal fabrics reinforced polyester hybrid composites. Results show that hybridization with glass fabric enhanced the performance properties. Similarly, addition of kapok fabric to sisal/ polyester composites enhanced the properties. The effect of alkali treatment of fabrics on impact strength of these composites was studied. Notched Izod impact strength of the hybrid composites exhibited great enhancement (34%). Analysis of fabric distribution in the composite and fracture surface was performed to study the breakage and fracture mechanism of the fabric. Also, we studied the thermal properties of kapok/glass and kapok/sisal fabric reinforced polyester composites. [ABSTRACT FROM AUTHOR]

The natural fiber composites of sisal/silk unsaturated polyester based hybrid composites with different fiber lengths were prepared. Sisal silk fiber at a ratio of 1 : 1 has been incorporated with unsaturated polyester resin with different fiber lengths such as 1, 2, and 3 cm. The variation of mechanical properties such as tensile, flexural, and compressive strengths of these composites with different fiber lengths has been studied. In the present work a hand lay-up method was used for making the composites. Sisal fibers are treated with NaOH and the effect of alkali treatment on the tensile, flexural, and compressive properties of the sisal/silk hybrid composites has also been studied. Significant improvement in tensile, flexural, and compressive strengths of the sisal/silk hybrid composites has been observed by these treatments. [ABSTRACT FROM AUTHOR]

The unsaturated polyester resin based sisal/glass hybrid composites were developed using the hand lay-up technique. Chemical resistance tests of these hybrid composites were performed in order to probe whether these composites can be used for making articles that are resistant to chemicals. The hybrid samples and the matrix have been tested for various acids, alkalis, and solvents. It is observed from the results that the developed hybrid composites are resistant to all the tested chemicals except carbon tetrachloride. [ABSTRACT FROM AUTHOR]

In order to evaluate the effect of processing conditions, composites of MaterBi-Y matrix with 15 wt% sisal fibers are obtained with different temperature profiles and speeds of rotation of the screw, using a twin-screw extruder. Three different temperature profiles are selected. The speeds of rotation are 25, 60, and 80 rpm. The samples are obtained by compression at 180°C and 700 MPa for 10 min. The mechanical properties of composites increase when the rotation speed changes from 25 to 60 rpm and then decreases. Fiber breakage increases with rotational speed, but aspect ratio increases too. Increased modulus with fiber aspect ratio is easily understood because longer fibers carry more tensile loads as a result of increase in transfer length. The decrease in the mechanical properties at a high rotational speed can be due to the degradation of the matrix. The impact properties increase when temperature increases. The decrease in impact properties at temperatures above 185°C can be due to the thermal decomposition of the material. [ABSTRACT FROM AUTHOR]

The variation of tensile strength of unsaturated polyester based sisal-glass hybrid composites with fiber loading has been studied. The tensile strength of these hybrid composites has been found to be higher than that of the matrix. The effects of NaOH treatment and trimethoxy silane (coupling agent) treatment on the tensile properties of these sisal-glass hybrid composites have also been studied. Significant improvement in tensile strength of the sisal-glass hybrid composites has been observed by these treatments. [ABSTRACT FROM AUTHOR]

The variations of flexural strength and flexural modulus of unsaturated polyester-based sisal/glass hybrid composites with fiber content have been studied. The hybrid composites showed an increase in flexural properties with glass fiber loading. The effects of alkali treatment and silane treatment of fibers on the flexural properties of these sisal/glass hybrid composites have also been studied. No significant effect on the flexural properties has been observed by silane treatment but a small increase in these properties has been observed by alkali treatment. [ABSTRACT FROM AUTHOR]

The variations of impact strength and compressive strength of unsaturated polyester based sisal/glass hybrid composites with fiber loading have been studied. The impact strength of these hybrid composites has been found to be higher than that of the matrix, whereas a marginal decrease was observed in the compressive strength of the hybrid composites over that of the matrix. The effects of NaOH treatment and trimethoxy silane (coupling agent) treatment on the impact and compressive properties of these sisal/glass hybrid composites have also been studied. No significant improvement in impact strength of the sisal/glass hybrid composites has been observed by these treatments, whereas a marginal increase in compressive strength of these hybrid composites has been observed. [ABSTRACT FROM AUTHOR]

This study investigates the permeability-porosity relationship for glass and natural fiber mats. The estimation of the permeability-porosity relationship for glass mats is not new and has been investigated before by several authors, but in the present paper the same relationship was discovered for natural fibers. The experimental permeability values were fitted by the Carman-Kozeny equation with two fitting parameters: the Kozeny constant and the exponent of the porosity. The obtained permeability for the natural fiber mats shows higher values than glass fiber mat. [ABSTRACT FROM AUTHOR]

The natural fiber environmental friendly composites of untreated and alkali treated silk-sisal unsaturated polyester-based hybrid composites were prepared by using hand lay-up technique. The fiber length was taken as 2 cm and the sisal fibers were treated with 2% NaOH. The chemical resistance of the treated and untreated silk/sisal hybrid composites to various acids, alkalis, and solvents was studied. The chemical resistance tests of these hybrid composites were performed in order to find out whether these composites can be used for manufacturing products that are resistant to chemicals. [ABSTRACT FROM AUTHOR]