Top PDF Effect of chemicals treatment and fiber loading on mechanical properties of borassus (Toddy palm) fiber/epoxy composites

Effect of chemicals treatment and fiber loading on mechanical properties of borassus (Toddy palm) fiber/epoxy composites

Effect of chemicals treatment and fiber loading on mechanical properties of borassus (Toddy palm) fiber/epoxy composites

In the present work the authors prepared a new composite system using Borassus fruit fibers as reinforcement and epoxy as resin matrix. Epoxy resins are used widely in industry because of their strong adhesive properties, popular thermoset, excellent chemical resistance and better mechanical properties [15]. Borassus (Toddy or Palmyra Palm) (Fig. 1a), is a member of palm tree family, normally found in the tropical regions of Africa, Asia and New Guinea. The Palmyra palm has been one of the most important trees, economically useful and widely cultivated in Cambodia and India, where it is used over 800 different ways. These fruits contain cellulosic semisolid flush, which is armored by the fibers. A detailed study of alkali treatment effect on morphology, mechanical and thermal properties of these fibers was reported in the literature [16] and suggested that these fibers could be utilized as reinforcement component in composite manufacturing. Borassus fruit fibers are inexpensive, abundantly available, eco-friendly and hence it is essential to explore the potential utility of these fibers to the technical world. In an endeavor, we recently developed natural fiber reinforced polymer matrix composites, using Borassus fruit fiber as reinforcement [17-19]. In this work, we treated Borassus fruit fibers by alkali, silane (3-aminopropyltriethoxysilane) and alkali combined with silane to improve tensile properties of composites. From a literature review it is clear that no work has been reported on mechanical performance of alkali and silane treated Borassus fiber/epoxy composites. The treatment effects on the fibers were characterized by scanning electron microscopy and infrared spectroscopy. Thus, the aim of this study was to prepare composites by chemically modified Borassus fibers with epoxy matrix and subsequently to characterize their structural, tensile, morphological and chemical resistance properties.
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Physical and Mechanical Properties of Bi-directional Jute Fiber Epoxy Composites

Physical and Mechanical Properties of Bi-directional Jute Fiber Epoxy Composites

During last few years, the interest in using natural fibers as reinforcement in polymers has increased dramatically. Natural fibers are not only strong and lightweight but also relatively very cheap. In this research work, an investigation has been carried out to make use of jute fiber, a natural fiber abundantly available in India. The present work describes the development and characterization of a new set of natural fiber based polymer composites consisting of bidirectional jute fiber mat as reinforcement and epoxy resin as matrix material. The composites are fabricated using hand lay-up technique and are characterized with respect to their physical and mechanical properties. Experiments are carried out to study the effect of fiber loading on the physical and mechanical behavior of these composites. Result shows the significant effect of fiber loading on the mechanical properties of the composites. Also, the formation of voids in the composites is an influencing factor on the mechanical properties.
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Mechanical Properties of Coir Fiber Reinforced Epoxy Resin Composites for Helmet Shell.

Mechanical Properties of Coir Fiber Reinforced Epoxy Resin Composites for Helmet Shell.

In Nigeria, coir fiber is harvested from coconut palm and is an abundant waste material. Large quantities of this waste are left in the field as under utilized. Information based on utilization of coir fiber for helmet production are limited. Hence, in this research, efforts have been made to treat the coir fiber before incorporating into epoxy ( bisphenol A diglycidyl ether) polymer matrix. Test materials have been prepared and series of filled epoxy composites with coir fiber loading (10- 50 wt.%), was used to study the effect of the filler content. The aim of this work is to study the mechanical properties of epoxy filled modified coir fiber composite for helmet shell production.
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Effect of Fiber Length and Fiber Loading on Impact Strength of Emu Feather Fiber Epoxy Composites

Effect of Fiber Length and Fiber Loading on Impact Strength of Emu Feather Fiber Epoxy Composites

A notable disadvantage of natural fibers is their polarity which makes it incompatible with hydrophobic matrix [8]. Many physical and chemical methods were developed to improve the bonding between the natural animal feathers and matrix material. Chemical treatment method of natural fibers was explained by [9].These methods make the feathers free from moisture and impurities. These methods affect the bonding of fiber and matrix. The Emu (Dromaius novaehollandiae) is the largest bird native to Australia and the only extant member of the genus Dromaius. It is also the second-largest extant bird in the world by height, after its ratite relative, the ostrich. There are three extant subspecies of Emus in Australia. In the present work emu feathers were selected as fibers because, Emu Chicken feathers are waste products of the poultry industry. Billions of kilograms of waste feathers are generated each year by poultry processing plants, creating a serious solid waste problem. The objective of the study is to investigate the effect of length and percentage weight of feather on mechanical properties of epoxy polymer composites.
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EFFECT OF WATER ABSORPTION ON THE MECHANICAL PROPERTIES \OF FLAX FIBER REINFORCED EPOXY COMPOSITES

EFFECT OF WATER ABSORPTION ON THE MECHANICAL PROPERTIES \OF FLAX FIBER REINFORCED EPOXY COMPOSITES

To have durable flax fibre reinforced com- posites, some significant studies have been con- ducted. Improving the poor environmental and dimensional stability of lignocellulosic materials is good to modify the tensile properties of flax fibres [8]. In the study by Stamboulis et al. [8], the environmental behavior of flax mat reinforced composites is investigated by monitoring the moisture absorption and swelling, and measuring the residual mechanical properties of the com- posites at different moisture levels. It confirmed that the moisture absorption and swelling of the Duralin treated flax composites is approximately 30% lower than that of the composites based on untreated flax fibres. Dhakal [6] found that hemp fiber reinforced polyester corresponding to 0, 0.15, 0.21 and 0.26 fibre volume fractions, re- spectively, immersed at room temperature for 888 h is 0.879, 5.63, 8.16 and 10.97%, respectively. Water absorption value increased with increasing fiber loading. Similar results have been obtained in this study. This phenomenon can be explained by considering the water uptake characteristics of flax fibre. When the composite is exposed to moisture, the hydrophilic flax fibers swell. As a result of fibre swelling, micro cracking of the brittle thermosetting resin (like epoxy) occurs [6].
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Effect of soil burial on mechanical properties of bamboo fiber reinforced epoxy composites

Effect of soil burial on mechanical properties of bamboo fiber reinforced epoxy composites

A hand lay-up method was adopted for the fabrication of BFREC. The first layer of the bamboo fiber was arranged methodically on the epoxy adhesive and pressed gently using a spatula to ensure the fibers were soaked entirely in the resin. The second layer of resin was poured on the first layer of bamboo fibers for interfacial bonding. Another layer of bamboo fibers was manually aligned on top of the resin followed by addition of polymer resin layers. The amount of fiber to be used with respect to the resin was set at 40% fiber volume fractions following by the study by Chin et al. [11]. Chin et al. [11] studied the effect of bamboo fiber loading to the BFREC tensile and flexural strength. They found the BFREC with 40% fiber volume fractions is the strongest among all the specimen tested. These steps were repeated until the required fiber amount was all filled in the mould. A sheet of fiber cloth placed on top of the last resin layer before pressure was applied on the top of the mould. The BFREC was cured at room temperature for 24 hours to enable a cross-linking between the bamboo fiber and the thermosetting resin. Subsequently, the sample was post cured in oven at 110 °C for 4 hours.
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Mechanical Properties of Banana Fabric and Kenaf Fiber Reinforced Epoxy Composites: Effect of Treatment and Hybridization

Mechanical Properties of Banana Fabric and Kenaf Fiber Reinforced Epoxy Composites: Effect of Treatment and Hybridization

Banana fabric reinforced composite shows higher tensile strength and impact strength of about 87.5% and 122.8% more than hybrid samples. Hybrid banana/kenaf reinforced composite has higher elastic modulus about 44.2% and 42% higher than treated kenaf and banana samples. While treated kenaf and Hybrid sample has higher hardness about 82-83 shore D. Alkaline treatment shows a lot of improvement in the mechanical properties of kenaf fiber reinforced composite. Specifically, its tensile strength got improved by 54.17%. Finite element model and actual results are in 91% agreement with each other for a given strain. This study concludes that mechanical properties of kenaf fiber reinforced composites are improved after alkali treatment (6% NaOH) while hybridization of banana fabric and kenaf fiber shows mixed result, Elastic modulus of hybrid composite has improved while weaken tensile strength and impact strength properties.
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Effect of Mercerization of Mechanical Behavior of Banana Fiber Reinforced Epoxy Composites

Effect of Mercerization of Mechanical Behavior of Banana Fiber Reinforced Epoxy Composites

© 2019, IRJET | Impact Factor value: 7.211 | ISO 9001:2008 Certified Journal | Page 1877 between the matrix and fiber were increased drastically as observed by micrograph by them. The most effective treatment was alkali treatment as reported in their study. Raghvendra et al. [11] also used banana fiber in its short form but not with any plastic. They incorporated the fiber in rubber and established natural rubber based composites. They studied the mechanical properties of the fabricated composites. Venkateshwaran et al. [12] found that fiber length and its content were the most influential factor which determines the mechanical properties of the composites. In their study, they optimize the length of the fiber and produce a set of composites with varying content of fibers. The optimized results give best mechanical properties which include tensile strength and modulus, flexural strength and modulus and impact strength. Apart from that, they also study the water absorption behavior of the fabricated composite and found that length of the fiber is not a factor on which water absorption depend, rather it increases with increase in fiber content. Ramesh et al. [13] were also fabricated banana fiber reinforced polymer composites with thermoset polymer epoxy and experimentally determined its mechanical properties. Jorden et al. [14] improves the interfacial bonding between banana fiber and LDPE matrix with the help of chemical treatment. They used two different techniques for fiber treatment i.e. peroxide treatment and permanganate treatment. Muktha, and Gowda [15] focused their work on water absorption and fire resistance behavior of banana fiber reinforced polyester composites. They prepared specimen of two different thicknesses i.e. of 3 mm and 5 mm with same fiber volume fraction. In their analysis they found that water absorption and fire resistance capacity of 3 mm thick specimen is less than that of the 5 mm thick specimen. Against this background, an attempt has been made in this research work to develop short banana fiber (SBF) based epoxy composites using simple hand lay-up technique and to study their mechanical properties i.e. tensile strength, flexural strength, hardness and impact with varying fiber content and also to study the effect of surface modification of fiber on various mechanical properties.
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Statistical analysis of mechanical properties of Kenaf fiber/ Palmyra sprout/Glass fiber reinforced Epoxy composites using Taguchi method

Statistical analysis of mechanical properties of Kenaf fiber/ Palmyra sprout/Glass fiber reinforced Epoxy composites using Taguchi method

experiments to test the sensitivity of a set of response variables to a set of control parameters (or independent variables) by considering experiments in “orthogonal array” with an aim to attain the optimum setting of the control parameters. Orthogonal arrays provide a best set of well- balanced (minimum) experiments [4]. The S/N ratios, which are log functions of desired output, serve as the objective functions for optimization, help in data analysis and the prediction of the optimum results. There are three forms of S/N ratio that are of common interest for optimization of static problems. 1. Smaller-the-better, 2.Larger-the-better and 3.Nominal- the-best. Different factors affect the strength to a different degree. Analysis of variance is a better feel for the relative effect of the different factors obtained by the decomposition of variance [5, 6].A short Palmyra sprout, Kenaf, glass fiber epoxy reinforced composites have been developed by Handlayup technique with varying parameters like fibre loading ((0%, 7.5%, 15% by weight) and fibre condition at constant fibre length of 3mm [7].In this present study, Composites comprising of epoxy fortified with Palmyra sprout, Kenaf, glass fiber arranged by Handlayup with shifting weight divisions of fiber (0%, 7.5%, 15%). The created Palmyra sprout, Kenaf, glass fiber strengthened Epoxy composites tried for their mechanical properties [8].The main objective of this work is to determine the suitability of Palmyra sprout, Kenaf, glass fibers as reinforcement in the Epoxy matrix for making composites. The effect of the fiber content and the interfacial adhesion on the mechanical properties of Palmyra sprout, Kenaf, glass fiber /Epoxy composites prepared by Handlayup process was investigated. Taguchi method of analysis is uses to reduce total number of experiments. The experimental data is analyzed using Taguchi method for optimal conditions of input parameters. ANOVA carried out on experimental data to find the significant effect of the input parameters. 1 Materials
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Mechanical Properties of Carbon/Glass Fiber Reinforced Epoxy Hybrid Polymer Composites

Mechanical Properties of Carbon/Glass Fiber Reinforced Epoxy Hybrid Polymer Composites

studied. None of the mechanical properties, excluding the fracture energies show signs of a positive hybrid effect (Marom et al., 1978). Manders and Bader (1981) reported hybrid effect and failure strain enhancement of up to 50% for the glass fiber/carbon fiber/epoxy composite. The failure strain of the carbon phase increased as the relative proportion of carbon fiber was decreases and as the carbon fibers were more finely dispersed. Yerramalli and Waas (2003) have considered carbon/ glass hybrid composite with an overall fiber volume fraction of 30%. Splitting and kinking failures were noted while loading the hybrid laminates under static and dynamic loading rates. Zhang et al. (2012) studied the mechanical behavior of hybrid composites made of carbon/glass reinforcements and the processing method used is ‘wet lay-up’ which is not a best practice for obtaining high quality laminates. An addition of hard reinforcements such as silicon carbide, alumina and titanium carbide improves hardness, strength and wear resistance of the composites (Amar Patnaik et al., 2009; and Chauhan et al., 2009). The introduction of a glass fiber into a polymer matrix produces a composite material that results in an attractive combination of physical and mechanical properties which cannot be obtained with monolithic alloys (Schwartz, 1984). Among the various useful polymer matrices, vinyl ester is typically characterized by properties such as fluidity, corrosion resistance and high strength-weight ratio (Suresha et al., 2007). The advantages of Fiber-reinforced PMCs over traditional materials include greater mechanical strength, lighter weight, better dimensional stability, higher dielectric strength and corrosion resistance and flexibility to improve the
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Mechanical properties of abaca fiber reinforced polypropylene composites: Effect of chemical treatment by benzenediazonium chloride

Mechanical properties of abaca fiber reinforced polypropylene composites: Effect of chemical treatment by benzenediazonium chloride

Flexural strength of diazo treated composites is greater when compared to untreated composites and employing coupling agent further hiked the flexural strength which is evident from Fig. 4. The chemical treatment and the addition of coupling agent helped in the elimination of external fiber surface, enhanced cellulose content and fiber matrix bonding which might have led to the improvement in flexural properties (Libo et al., 2012). For untreated and diazo treated composites without coupling agents 40% fiber loading showed optimum flexural properties. For untreated and diazo treated compos- ites with coupling agents increment in flexural strength was observed as the fiber content surged up to 50%. For 40% fiber content, flexural strength of untreated composites containing coupling agents increased by 9.5% compared to untreated composites devoid of coupling agents. And diazo treated com- posites containing coupling agent showed 2.21% hike in tensile strength than diazo treated composites devoid of coupling agents for the same fiber loading. For 50% fiber loading, flex- ural strength of untreated composites with coupling agents increased by 64.91% compared to untreated composites with- out coupling agents. And diazo treated composites with cou- pling agent showed 36.84% increase in flexural strength compared to diazo treated composites without coupling agents for the same fiber loading.
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Mechanical Behavior of Coir Fiber Reinforced Epoxy Composites with Variable Fiber Lengths

Mechanical Behavior of Coir Fiber Reinforced Epoxy Composites with Variable Fiber Lengths

Monteiro et al. [4] The research showed that the coir fiber proportion could be increased to 80% and discovered that the composites became rigid up to 50% of the fiber loading and are composites such as agglomerates. Samal et al. [5] The mechanical, thermal and morphological features of polypropylene hybrid bamboo and glass fiber composites were prepared and examined. In order to enhance the fiber matrix interface bonding, the malefic anhydride grafted polypropylene (MAPP) has also been added to the composite. Compared to virgin polypropylene, the hybrid composite displays enhanced mechanical characteristics such as tensile, effect and bending strength. The fiber interface gap in the SEM composite micrograph was reduced. To regulate composite resistivity, the composites of hybrid polyester processed with other chemicals such as sodium carbonates, sodium hydroxide, acetic acid, benzene, carbon tetrachloride, ammonium hydroxide, toluene and water have been tested Reddy et al.[5]. The hybrid composites demonstrated outstanding chemical resistance and enhanced the tensile strength of the alkalized hybrid composite. Biswas et al. [7] conducted a survey on the meaning of fiber length on coir / epoxy composite mechanical personality. He has found that the composite hardness decreases by increasing the fiber length to 20 mm and then rises afterwards. They found that fiber length has a significant effect on improving mechanical characteristics such as tensile strength, bending strength and impact strength.
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An Investigation of Mechanical Properties of Honge Shell Fiber Reinforced Epoxy Composites

An Investigation of Mechanical Properties of Honge Shell Fiber Reinforced Epoxy Composites

30 Srinivas et al.[8] reported that it is possible to enhance the properties of composites through fiber surface modification by NaOH chemical treatment. The mechanical properties of chemically treated areca fiber composites show better results compared to natural untreated fibers. Impact energy increased from 3 Joules (untreated) to 5 Joules (treated) and hardness number increased from 23HRB to 28HRB. Anilkumar et al.[9] presented the mechanical properties such as tensile, flexural, and compression strength of eucalyptus fiber reinforced composites. The results showed that higher tensile strength of 70.08 MPa, flexural strength 60 MPa and compression strength 182.05 MPa was observed for fiber loading of 25 wt.%. The micrographs showed that there is poor fiber- matrix adhesion and more fiber pull out in 10wt.% fiber content. Tewari et al.[10] developed bagasse glass fiber composite material with 15%, 20%, 25% and 30% of bagasse fiber and 5% glass fiber. The addition of fiber increased the modulus of elasticity of epoxy. Bagasse glass reinforced fiber improves the impact strength of epoxy material due to more elasticity of fiber in comparison to matrix material. In the present study, honge shell fibers which are waste material while extracting honge seeds for the preparation of biodiesel, was used as reinforcement in polymer matrix.
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Evaluation of Mechanical Properties of Emu Feather Fiber Reinforced Epoxy Composites

Evaluation of Mechanical Properties of Emu Feather Fiber Reinforced Epoxy Composites

A notable disadvantage of natural fibers is their polarity which makes it incompatible with hydrophobic matrix [8]. Many physical and chemical methods were developed to improve the bonding between the natural animal feathers and matrix material. Chemical treatment method of natural fibers was explained by [9].These methods make the feathers free from moisture and impurities. These methods affect the bonding of fiber and matrix. The Emu (Dromaius novaehollandiae) is the largest bird native to Australia and the only extant member of the genus Dromaius. It is also the second-largest extant bird in the world by height, after its ratite relative, the ostrich. There are three extant subspecies of Emus in Australia. In the present work emu feathers were selected as fibers because, Emu Chicken feathers are waste products of the poultry industry. Billions of kilograms of waste feathers are generated each year by poultry processing plants, creating a serious solid waste problem. The objective of the study is to investigate the effect of length and percentage weight of feather on mechanical properties of epoxy polymer composites.
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Effect of Marble Particle on Physico-Mechanical behaviour of Glass Fiber Reinforced Epoxy Composites

Effect of Marble Particle on Physico-Mechanical behaviour of Glass Fiber Reinforced Epoxy Composites

Tensile properties were determined by an Instron 3369 machine at room temperature with a gauge length of 50 mm and a crosshead speed of 10mm/min. The test was repeated five times for each sample, and the average value was recorded. The tensile strength test results for the glass-epoxy composite filled with marble powder ranging from 0wt% to 15wt% are presented in Table 4. The results show that the addition of marble particulate resulted in a significant decrease in the tensile strength of the glass-epoxy (EGM) composite from 363.27 MPa to 281.64 MPa as shown in Fig. 2. The tensile strength of filled composites (EGM1, EGM2 and EGM3) is less as compared to the unfilled (EGM0) composite. Similar behaviors are observed by the previous researchers using glass-epoxy-rice husk composites [10]. The decreased in tensile strength of the composites was observed due filler content (5 wt% to 15wt %) leading poor adhesion between matrix, reinforcement and filler. This behavior is mainly due to the increase of void content on filler addition that resulted in the decrease of the interfacial bond strength between the filler particles and the resin matrix. Furthermore, the sharp corner of the irregular shaped filler particle induces stress concentration during tensile loading. The fillers cannot carry the load due to this de-bonding, which result in composite strength with increase in filler loading [20].
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Investigating the Effect of Fiber Concentration and Fiber Size on Mechanical Properties of Rice Husk Fiber Reinforced Polyester Composites

Investigating the Effect of Fiber Concentration and Fiber Size on Mechanical Properties of Rice Husk Fiber Reinforced Polyester Composites

Bisht and Gope [12] developed rice husk flour reinforced epoxy bio-composite and studied the influence of fiber treatment and weight fraction of rice husk on the mechanical behavior, in comparison with wood dust composite reinforced with epoxy. Fibre weight percentage was varied in steps of 10%, from 10% (lowest) to 40% (highest). They noted that addition of rice husk as filler was detrimental nearly to all mechanical characteristics of the resulting composite. It was observed of the 40 %wt untreated rice husks, that ultimate strength and Young's Modulus decreased by around 51% and 26.8% respectively. A close examination of results revealed a remarkable decrease in mechanical characteristics of composites which had more than 20 %wt filler loading. This led to the conclusion that fiber loading beyond 20% is not economical from the strength point of view. The decrease in tensile strength was attributed to the decreasing fiber-matrix interfacial bonding with addition of fibers, as well as agglomeration of rice husk fibers leading to the generation of voids between filler and matrix.
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A study on the effect of fiber loading and orientation on mechanical behaviour of jute fiber reinforced epoxy composites

A study on the effect of fiber loading and orientation on mechanical behaviour of jute fiber reinforced epoxy composites

Latest technology not only involves information about new product but also in making at low cost so, for that particular reason before making any kind of polymer matrix based composites individual should know what is the advantages and disadvantages of this matrix over one another. Thermosetting resin is the first choice of any company nowadays due to its availability, ease of processing, the existence of large database and low material cost. Thermosetting resins like epoxies are available in a low viscosity liquid form that has excellent flow properties to facilitate the penetration of fiber bundles and wetting of fiber surface. The manufacturing cost of the thermoplastic composite is high in comparison to the thermosets due to its longer shelf life, hygroscopic nature and need of refrigeration before processing. Quality control in thermoset is much more difficult because it contains large no of ingredient such as, base epoxies, curing agent, catalyst, flow control agent and property modifier. The toughness of the thermoplastics is more than that of thermosets due to these thermoplastics shows good resistance to delamination. Thermoplastics are the high molecular weight material because of it before processing it ether to be heated at high temperature or should be treated with a polar solvent to lower its viscosity for ease of processing. Processing cost is also high in case of thermoplastics because it needs high pressure and temperature for processing.
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Mechanical Properties of Luffa Fiber and Ground nut Reinforced Epoxy Polymer Hybrid Composites

Mechanical Properties of Luffa Fiber and Ground nut Reinforced Epoxy Polymer Hybrid Composites

Many researchers developed composites containing both natural and synthetic fillers and these materials were termed as hybrid composites. The hybrid composites showed better impact and compressive properties than mono- filler FRPs [3-4]. The mechanical properties of short random oil palm fiber reinforced epoxy (OPF/epoxy) composites were studied by Mohd zuhri et al [5]. In their study, composite plates with different volume fractions (5, 10, 15 and 20 vol%) of oil palm fiber were fabricated by hand-layup technique. The tensile and flexural properties showed inverse variation with fibre loading. The maximum tensile strength values were obtained for the sample with 5 vol% fraction of fibres and beyond that there was no significant change. From this research, it is obvious that oil palm fibre is not suitable for structural applications. Mansour Rokbi et al. [6] analysed the influence of alkaline treatments on the flexural properties of Alfa fibre to determine the optimum conditions for alkaline treatment. The experimental results obtained from a treatment with 10% NaOH in 24h, showed improvement in the flexural strength and flexural modulus, from 23 MPa to 57 MPa and from 1.16 GPa to 3.04 GPa respectively.
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A Study on the Effect of Fiber Parameters on the Mechanical Behavior of Bamboo-Glass Fiber Reinforced Epoxy Based Hybrid Composites

A Study on the Effect of Fiber Parameters on the Mechanical Behavior of Bamboo-Glass Fiber Reinforced Epoxy Based Hybrid Composites

Polymeric materials reinforced with synthetic fibers such as glass, carbon, and aramid offer the advantages of higher stiffness and strength to weight ratio as compared to conventional construction materials like wood, concrete, and steel. Despite these advantages, the widespread use of synthetic fiber reinforced polymer composites has a tendency to decline because of their high initial costs and adverse environmental impact. In recent years, the natural fiber composites have attracted substantial importance among the structural materials. There has been a fast growing interest in using the natural fibers as reinforcements in the composites. The attractive features of natural fibers are their low cost, light weight, high specific modulus, renewability and biodegradability. Among many of the natural fibers (like jute, sisal, bamboo, coir, banana etc.), bamboo fiber is one of the most promising one, because of its low cost, light -weight, short growth cycle and high availability. Use of bamboo fiber can help to reduce the demand for wood fibers and environmental impacts associated with wood fiber harvesting, hence considerably lowering the stress on wood forests. Bamboo fiber reinforced polymer composites have moderate mechanical properties but their properties can be greatly enhanced by mixing of synthetic fibers or by the treatment of fiber in the alkali medium. Attempts have been made in this research work not only to explore the potential utilization of bamboo fiber but also a means of mixing of other synthetic fiber in the polymer composites for making value added products. Nine different types of hybrid composites (bamboo and glass fiber) have been prepared by hand lay up technique for physical and mechanical characterizations.
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The Mechanical Properties of UHMWPE Fiber-Knitted Composites

The Mechanical Properties of UHMWPE Fiber-Knitted Composites

The surface morphology of the UHMWPE fiber was studied using a TM3030 SEM. As shown in Figure 1 and Figure 2, the surface of the original UHMWPE fiber was smooth. However, after modification, the surface of the fibers became rough as a result of corrosion. There was an increase in the surface roughness and contact area with the resin, which increased the bond between the yarn and the resin because the surface of the UHMWPE fiber contained many small horizontally aligned cracks. The vertical direction also featured deep grooves and a symmetrical distribution, and the crack depth was up to 1 to 2 microns, which is sufficient to allow chemical molecules to enter and contact the material, accelerating oxidation and promoting corrosion. However, the fiber surface exhibited prominent candle-like carved structures and longitudinal surface cracks, and the fiber was damaged by an increase in the processing time and processing temperature; thus, it is important to control the experimental time and temperature. From a micro-scale perspective, the fiber surface contact angle decreased, and the surface contained oxygen-rich polar groups, such as light base fiber, that increased after processing. The surface polarity difference improved the fiber non-crystalline surface area. It contained candle-like structures, the number of folded chain crystals decreased, and amylose crystallization increased. The fiber crystallinity increased after chromium treatment. Increased chromium acid treatment liquid with a strong oxidizing agent generally results in physical
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