It is a platitude that technological advances depends on fosters in the sector of materials. If sufficient materials to bear the service loads and conditions are not available then one does not have to be a skilful to realize the most advanced turbine or air-craft pattern. Whatsoever the field may be, the ultimate restriction on progression is to be governed by materials. Composite materials in this regard signify a big step in the constant accumulation of optimization in materials. Composites are mixture of two or more materials such as reinforced plastics, metals, or ceramics. The reinforcements may be in the form of fibers, particles, whiskers or lamellae and are embedded in a suitable matrix, thereby providing a material that contains the most useful properties of the constituents. High structural strength, glass fibrereinforced plastics were developed in the early 1940’s and the application of reinforced plastics composites, the glass fibre provides strength and stiffness while the plastic matrix provides the temperature capabilities of the composite. Initially the glass fibres were incorporated in a polyester matrix which could withstand temperature up to 200 ⁰ C. They were applied in car bodies, appliances, boats etc., because of their light weight and mitigate of production. Intricate composites parts can be made by injection moulding. Polymer matrices are usually thermosets such as epoxies. Later, resins which can withstand high temperatures, of the order of 300⁰C were developed such as polyamides. Other thermo setting resins include benzocylobutene – bismaleimides. Advanced composites are manufactured by using the above polymers with reinforcements of stronger fibres such as aramid and carbon. As a result advanced composites are finding increasing applications in aircraft, automotive industry, etc. In order to reduce the manufacturing time, thermoplastics polymers such as polyether – ether ketone (PEEK) have been developed. The plastic requires only a short revelation to heat to soften the plastics, thereby allowing faster processing of the composite.
The manufacturing of naturalfibrecomposites includes the use of thermoplastics polymer such us polypropylene, polyethylene, and polyamides combined with the naturalfibre random mat or short fibres through injection mold- ing, compounding, extrusion, or thermoforming processes. Automotive industry is a clear example, where their use for nonstructural components can be found  as interior glove box and door panels or exterior floor panels. In the case of naturalfibrereinforced thermosetting matrix composite, the most used manufacturing process in the literature has been hand lay-up and liquid compression molding, for nonwoven or random mats due to the low costs associated with these techniques. Nowadays, research and industrial applications focus on the aligned naturalfibrecomposites applications using continuous natural textile reinforcements like unidirec- tional (UD), woven, and noncrimp fabrics, at this time, com- mercially available. The potential of use of naturalfibre fabrics will improve significantly the composite properties for engi- neering applications or high performance naturalfibre com- posites. Additionally, in combination of thermosetting poly- mer matrices, it will allow the use of well-established man- ufacturing techniques as liquid composite moulding (LCM) processes, as resin transfer moulding (RTM) or vacuum infu- sion. Only a few studies  have been focused on the pro- cessing of natural fiber composites by LCM processes. This study will focus on the manufacture of flax fibre woven fabric reinforced bioepoxy composites by RTM process and the evaluation of their mechanical properties. In order to study the potential of use of these composites in outdoor applica- tions or humid environmental conditions, the water absorp- tion behavior of flax fibre bioepoxy composites at room temperature and various weight fractions of fibre has been investigated as well as its effect on the mechanical properties (tensile and flexural).
Long fibre kenaf were used for the fibre reinforcements. The matrix material used in this study was based on the unsaturated polyester resin trade name Reservol P9509 which was supplied by Revertex (Malaysia) Sdn. Bhd. This type of resin is rigid, and with low reactivity, thixotropic general purpose orthophthalic. The matrix was mixed with curing catalyst, methyl ethyl ketone peroxide (MEKP) at a concentration of 0.01 w/w (weight ratio) of the matrix for curing. Unsaturated polyester has many advantages compared to other thermosetting resins including room temperature and low pressure moulding capabilities which make it particularly valuable for large component manufacturing at a relatively low cost (El-Sayed et al., 1995).
The experimental study on the effect of fibre loading and orientation on physical, mechanical and waterabsorptionbehaviour of jute and cotton/glass fibrereinforced polyester based hybrid composites leads to the following conclusions: 1. The successful fabrications of a new class of polyester based hybrid compositesreinforced with jute ,cotton and glass fibre have been done. The present investigation revealed that fibre loading and orientation significantly influences the different properties of composites. The maximum hardness, flexural strength and tensile strength,impact strength,hardness,density is obtained for compositesreinforced with 20wt% jute fibre loading. 2. The waterabsorption rate gradually increases with increase in fibre loading irrespective of fibre orientation. The maximum waterabsorption is obtained for composites with 25 wt% fibre loading irrespective of fibre orientation. As far as effect of fibre orientation on the waterabsorption of composites is concerned there is not much influence is observed.
Abstract - Fiber reinforced polymer composites have a wide variety of applications as a class of structural materials because of their advantages such as ease of manufacturing, comparatively minimum cost of production & greater stability. The fiber supports polymers can be either factitious or inherent. In spite of synthetic fibers like glass and carbon acquire high specific strength, their field of applications is limited because of their higher costs of fabrication. In recent times, there is a developing concern in hybrid composites that are made by reinforcement of two or more different types of fibers in a single matrix, considering these materials obtain a limit of properties that cannot be obtained with an appropriate support. In addition, material charges can be slow down by careful selection of supporting fibers. Mechanical properties of a composite material depend on many factors. In this connection, the objective of the present research work is to study the effect of fiber content on the mechanical and waterabsorptionbehaviour of sisal and banana fibrereinforced epoxy based hybrid composites
In composite axial crushing, less works have done on using naturalfibrereinforced plastics. In the review of composite axial crushing , glass and carbon fibrereinforced plastics are heavily studied. Different shapes, structure geometries, as well as type of fracture modes which contributed the best energy absorption were reviewed. Abosbaia et al.  conducted axial crushing on cotton fabric. In the test, filament winding fabrication has been used and stacking sequence concept was adopted. From the test, cotton was crushed progressively. Furthermore, folding formation was observed after peak load at 5.43kN. On the other hand, Mahdi et al.  tested on solid cones made of oil palm fibre and coir fibrereinforced polyester composites. In their study, it was revealed that cone vertex angle influenced peak load. A part from that, type of fibre used in the test affected on the crashworthiness parameters. Although all the specimens crushed progressively, specific energy absorption (SEA) of naturalfibrereinforcedcomposites were relatively low compare to carbon and glass fibrereinforced plastics which for cotton, oil palm and coir reinforced plastics composite are at 2.501kJ/kg, 0.633kJ/kg and 0.577kJ/kg,
Fast-growing scientific work is focusing on alternative sources to replace modern synthetic fibre materials due to the adverse effects caused by petroleum-based materials. Naturalfibre possesses high potential as a replacement for synthetic fibre and petroleum- based products. These materials are not only greener and environmental-friendly, but also safe for human health. As such, this study investigated the influence of compatibilising agent of maleated anhydride polyethylene (MAPE) on mechanical performance of pineapple leaf fibre (PALF) reinforced polylactic acid (PLA). The raw materials, such as PALF, PLA, and MAPE, were mixed by using a hot roller mixer machine and hot compression moulding at 190ºC. The specimens were then tested for waterabsorption and flexibility. The specimens were submerged in water for 0, 7, 14, and 21 days. Three types of tests were conducted, namely waterabsorption, tensile, and flexural assessments. The results of waterabsorption, tensile, and flexural tests for the untreated PALF composite (UPALF) and treated PLAF composite (TPALF) were recorded and explained. As a conclusion, composite materials based on hydrophilic naturalfibre may reduce the tensile and flexural properties of the composite.
Page | 45 Bagasse, the fibre from sugar cane processing was first utilized in America in the 1920s to manufacture composite panels . Currently, building panels and roofing sheets made from bagasse fibrereinforced phenolic composites are being used in houses in Philippines, Jamaica and Ghana . Traditional roof tiles are predominantly made from materials such as clay, cement and steel, which have disadvantages of weight that result in high design (dead weight) and installation loads (live weight). Another disadvantage of such materials is the negative environmental impact associated with high embodied energy, material waste and pollution from the manufacturing processes (air, land and water) . Roof sheet materials must be designed to sustain dead load, live load, wind load and in other cases, snow load. The material must be lightweight, fire resistant, water resistant and weather resistant (such as resistance to ultraviolet light) . Roof sheet materials that have substituted traditional ones include the utilization of recycled paper reinforced cellulose fibre. Dweib et al  used bio-based materials to manufacture a NFC sandwich roof structure and structural beams. Recycled paper was incorporated into composite sheets and structural unit beams and the resulting strength and stiffness was found to be comparable with the currently used materials for roof construction [Figure 2.18 (d)] . In another study , sisal fibres were manually cast on corrugated roof sheets thereafter, strength of the sheets was evaluated. The authors concluded that the strength of sisal fibre corrugated roof sheets (towards splitting due to direct and impact loads) was improved compared to unreinforced corrugated sheets. John et al  concluded that sisal and coir fibrecomposites have the potential to replace asbestos in roofing components.
The amount of water absorbed by a sample varies as a function of its composition, dimensions, void fraction (available free volume), temperature, surface area, surface protection, and exposure time. The effects of moisture and temperature of composites on several performance parameters, such as tensile and shear strengths, elastic moduli, fatigue behavior, creep, rupture stress, response to dynamic impact, and electrical resistance, has been investigated (Symington et al., 2009). UmitHuner (2006) studied the effect of waterabsorption on the mechanical properties of flax fiber reinforced epoxy composites. Flax fiber reinforced epoxy composites were subjected to water immersion tests in order to study the effects of waterabsorption on the mechanical properties. Epoxy composites specimens containing 0, 1, 5 and 10% fiber weight were prepared. Waterabsorption tests were conducted by immersing specimens in a deionized water bath at 25 °C and 90°C for different time durations. The tensile and flexural properties of water immersed specimens subjected to both aging conditions were evaluated and compared alongside dry composite specimens. The percentage of moisture uptake increased as the fiber volume fraction increased due to the high cellulose content. The tensile and flexural properties of reinforced epoxy specimens were found to decrease with increase in percentage moisture uptake. Moisture induced degradation of composite sampleswas significant at elevated temperature.
The results of the investigation into waterabsorption of HDPE reinforced with untreated and treated RPFs are presented in Figs. 4.39 – 4.41 (and Table H.1 in Appendix H). It can be observed that the previous finding of a two-stage water saturation behaviour for non-treated (Fig. 4.8) and treated (Fig. 4.9) fibers also occurred in all composites specimens. The molded HDPE did not show a two-stage water saturation behaviour indicating that the waterabsorption behavior of the composites was controlled by the fibers. The first saturation level is practically the same for composites containing 5 – 20 wt.% untreated fibers. Waterabsorption at the second saturation stage also increased with increasing fiber content for compositesreinforced with treated and untreated fibers. Previous studies have also shown that water uptake for NF reinforced thermoplastic composites increased with fiber content [10,99,101,102,199]. The amount of water absorbed in HDPE composites containing alkali and acidic treated fibers was lower than that of untreated fiber. A maximum value of 0.41, 0.36, and 0.31 wt.% water absorbed was observed for reinforced untreated, alkaline and acidic treated fibers HDPE composites respectively. The decrease in the amount of water absorbed in HDPE composite containing alkali and acidic treated fibers is due to the removal of hydroxyl groups in the hemicellulose of RPF after chemical treatments . Jacob et al.  also observed that apart from the removal of non-cellulosic component in natural rubber composite reinforced with 4% NaOH chemically modified sisal fibers, increase in crystallinity of the treated fibers reduced the level of water absorbed by the composites. Chawla  also reported that increase in the degree crystallinity of the NF reinforcedcomposites lowered the amount of water absorbed. The findings from these authors with the increase in fractional crystallinity of HDPE composites (section 4.2.8) agrees with the low water absorbed in HDPE composites containing treated fibers in comparison to untreated fibers.
Natural fibres are produced from renewable resources, they are biodegradable and relatively inexpensive compared to the traditionally used synthetic fibres . Fibres of this type are beginning to find their way into commercial applications such as in automotive industries and household applications, for example, hemp and flax, are successfully used as packaging material, interior panels in vehicles, and building components, among others. In addition, natural fibres like banana, sisal, hemp and flax, jute, coconut, local fibres and oil palm have attracted technologist and scientist in consumer goods, low costs housing and other civil structures . There are many plant fibres available which has potential to be applied in industries as raw materials such as pineapple leaf fibre, kenaf, coir, abaca, sisal, cotton, jute, bamboo, banana, Palmyra, talipot, hemp, and flex .
Chemical Test: The chemical resistance test of the composites was studied as per ASTMD standard 543-87 Method. The chemicals mainly acids is concentrated hydrochloric acid, concentrated nitric acid, acetic acid, the alkalis namely aqueous solutions of sodium hydroxide, sodium carbonate, and solvents-benzene, carbon tetra chloride and Water were selected.
At the dry scale, and concerning the needle-punching density, Das et al.  report that higher punch densities result in denser fabrics with higher tensile strength, abrasion resistance, bursting strength, and tear resistance, but also results in greater amounts of fibre damage and fibre breakage. On needle-punched jute nonwovens, Maity  has exhibited the anisotropy of the tensile behaviour between MD / CD directions (Machine direction / Cross direction). With increasing punch density, the strength of nonwoven fabric reaches the maximum level and then falls [24–29]. Ishikawa et al.  have recently studied the e ff ect of needle-punching conditions on fibre orientations of non-woven structures by X-ray computed tomography and have linked these orientations to the tensile behaviour of nonwoven. At composite scales. A large number of studies report mechanical properties obtained on flax / PP nonwoven composites. For a Flax / Epoxy nonwoven composite of 300 g / m 2 (areal density) and with a Vf equal to 30%, Bensadoun et al.  have found a tensile strength of 84 MPa, a tensile failure strain of 1.49%, and a first tensile sti ff ness of 7.3 GPa along with a second tensile sti ff ness of 5.6 GPa. This decreased the strain softening. Miao et al. , from a needle-punched carded nonwoven, have dissociated, for a Flax / PP composite (Vf = 28.5%), the longitudinal properties (Tensile: Strength 88 MPa, Modulus: 5 GPa, Flexural: Strength 90 MPa, Modulus: 6.28 GPa) to the perpendicular properties (Tensile: Strength 33 MPa, Modulus: 2.73 GPa, Flexural: Strength 54 MPa, Modulus: 2.74 GPa). These results are in the same range as those given by Pickering et al.  in case of Flax nonwoven thermoplastic with a tensile modulus between 4–8 GPa and tensile strength of 40–60 MPa. With an experimental study on Flax / PP nonwovens, Giri Dev et al.  have reported recently that the increase in needling density led to the deterioration of mechanical properties (tensile and flexural) of composites due to fibre breakage and voids.
In recent years, due to growing environmental and ecological concerns, many studies have focused on the use of renewable resources as a starting material or blending component in the polymer resin formation. To tap to the mass production of palm oil in Malaysia, this study focuses on developing a novel hybrid glass/kenaf fiber reinforced epoxy composites from acrylated epoxidized palm oil (AEPO) filled organo modified montmorrillonite nanoclay (OMMT) and cured with bio-based hardener. The effects of AEPO and OMMT loading on mechanical and thermal properties, morphology as well as waterabsorption properties of epoxy/AEPO nanocomposites were investigated. The amounts of AEPO in epoxy resin were varied at 10, 20 and 30 wt% and the OMMT loadings were varied at 1, 1.5 and 2 phr. The results revealed that the impact strength and ductility properties of epoxy/AEPO resin improved with AEPO loading. The highest improvement of impact strength was indicated by epoxy/AEPO resin with 30 wt% AEPO loading, representing 57.8% higher than the neat epoxy resin. However, the strength and modulus of epoxy/AEPO resins were reduced with increasing of AEPO content. The addition of OMMT improved the modulus and thermal stability of nanocomposites with the optimum balanced properties at 10 wt% AEPO and 1.5 phr OMMT nanoclay loading. At this loading, tensile modulus of epoxy resin with 10 wt% AEPO loading improved 45.6 % higher than the neat epoxy/AEPO resin. The thermogravimetric analysis and dynamic mechanical analysis results also revealed that the thermal stability and glass transition temperature of epoxy/AEPO nanocomposites improved with the addition of OMMT up to 1.5 phr OMMT loading. The hybrid glass/kenaf fiber composites were fabricated using hand lay-up technique. The moisture absorptionbehaviour and its effects on the flexural properties of hybrid glass/kenaf fiber composites were investigated. The waterabsorption studies showed that the hybridization between glass and kenaf fibers significantly affected the waterabsorption and flexural strength of the composites. The alternated layering sequence of GKKG (where, G and K stands for glass and kenaf fiber, respectively) gave the best flexural properties of the resulted hybrid kenaf/glass fiber reinforced epoxy/AEPO filled OMMT composites. The overall results showed that montmorrilonite filled epoxy/AEPO hybrid kenaf/glass fiber composites are potential materials which could be utilized for applications in automotive panels, wall or floor panels, furniture, and housing construction materials.
The comparison between conventional fibre and naturalfibre had been shown some similarities in the mechanical properties such as tensile strength, young’s modulus, flexural strength and flexural modulus. However, the impact strength is still low for both materials. One of the main important aspects of the behaviour of natural plant fibrereinforced polymeric composites is their response to an impact load and the capacity of the composites to withstand it during their service life. Such damage may be caused by bumps or crashes and falling objects and debris. Some of the reported work has suggested that naturalfibrecomposites are very sensitive to impact loading. The major drawback is its low impact strength as compared to glass fibrereinforced thermoplastic and thermosets composites. In the broader context, assessing the impact resistance of a composite material is always difficult since the damage manifests itself in different forms such as delamination at the interface, fibre breakage, matrix cracking and fibre pulls out. Due to their complexity, many of their characteristics still remain unresolved.
In recent past decades, natural fibres have been a suitable replacement of synthetic fibres for polymer based composites because of its extraordinary advantages such as low density, recyclability, high specific strength and modulus and less wear and tear [1-3]. These fibres also offer the benefits of low cost associated with processing as compared synthetic fibres such as glass, carbon, aramid and nylon [4-5]. In addition, these fibres have some other dominating properties over the synthetic fibres like huge availability and biodegradability [6-8]. However, these fibres are troubled by some disadvantages also i.e. poor resistance to waterabsorption, low impact strength and poor compatibility [9-10]. Another main disadvantage of composite of these fibres is poor mechanical performance over the synthetic fibrereinforced polymer composite. Hence, it can be concluded that composite of natural fibres cannot be better option for structural applications. The disadvantages of these fibres can be overcome by surface modifications using various types of chemical treatments [11-13].
In light of the above, the candidate found it necessary to study the machinability and two body abrasion of epoxy composites based on date palm fibres and glass fibres. In this study, the project was divided into three stages: 1) studying the interfacial adhesion properties of date palm fibre with an epoxy matrix, 2) investigating the machinability of date palm or glass fibre/epoxy composites and 3) investigating the two body abrasive behaviour of the developed composites. To conduct the machining experiments, a new dynamometer adapted with a drilling machine was designed and manufactured to measure cutting pressure and cutting force at different operating parameters. An analysis of variance (ANOVA) approach was developed to discover the correlation between the operating parameters and the machinability of the epoxy composites in terms of the drilled hole accuracy. In terms of tribology, two body abrasive testing using a tribo-test machine was conducted using block on disk against various SiC at different applied loads in the range 5–20 N. The specific wear rate, friction coefficient and wear mechanism were studied and the surface morphology was examined using scanning electron microscopy (SEM) to observe the worn surfaces of the specimens after each test.
were removed from the surface. So the bonding between the matrix and fibre was improved. Because of increase in the adhesion the mechanical properties can be increased. The SEM images shows that the with the surface treatment the surface of fibre becomes smooth and the bonding between fibres and matrix increased. Venkata Ramana and Ramprasad studied the impact, tensile strength and flexural strength of carbon/jute hybrid composite. Hand layup technique was used to prepare the composites. Carbon epoxy, jute epoxy and jute-carbon epoxy are the three specimens. The results show that the carbon epoxy having higher tensile strength of 370 Mpa and flexural strength of 11.41 GA. Jute carbon epoxy shows properties 16 times greater than the jute epoxy composite. And jute epoxy shows the higher impact strength of 2 Joules. So by incorporating carbon fibre in the jute epoxy composites the properties are increased. Muktha and Keerthi Gowda  investigated fire resistance and waterabsorptionbehaviour of polyeater compositesreinforced with untreated banana. The results show that with increase in the fibre volume fraction reduces the burning rate and increases the thermal stability. And the waterabsorption was increases with the fibre volume fraction due to presence of cellulose. By the results naturalfibre can be used at where there is less contact with the water and fire. Hari om maurya et.al. studied the mechanical properties of short sisal reinforced epoxy composite 5,10,15 and 20 mm fibres were used. Results show that with increase in the length of fibre impact strength increases found a maximum value of 27.62 kJ/m2 at 20 mm fibrereinforcedcomposites. But there is no change in the tensile strength. 10 mm sisal fibrecomposites shows
a) SISAL FIBRE ( Agave sisalana )- The Sisal fibres used in this work have been supplied from Vrushka Composites, Tamil Nadu. Sisal fiber has high specific strength and modulus, easy availability, low price, reusability, etc. The Sisal plant has a life-span of 7-10 years and generally produces 200-250 commercially usable leaves and each one contains an average of around 1000 fibres . The fibers obtained are dried in sun which whitens the fiber. After drying, the fibers are ready for knotting. Sisal fibres are being primarily used in high strength ropes, especially in South India.
Flexural secant moduli (Figure 7.19) show poor correlation with theoretical moduli which are over-predicted. Flexural linear moduli (Figure 7.20) are also lower than predicted moduli. It is clear from these results that a simple rule of mixtures as applied in this work is not suitable for predicting flexural moduli. This is likely to be because of three reasons; the first being that theoretical moduli were calculated using the tensile moduli of resins and not the flexural moduli, second because the compressive behaviour of the fibres is not known and third because the value of the efficiency factor (η) does not take into account the out-of-plane orientation of the fibres caused by the needle-punching manufacturing process. For CSM, the value of η is typically set equal to 0.3 and this value was used for all calculations. However, in CSM the fibres are orientated in the plane. This means that in kenaf fibrereinforcedcomposites there are fewer fibres orientated in the plane of the applied load. Thus, using a lower value of η may result in better correlation with experimental results.