Conventionally, in aerospace, automotive and packaging industries, synthetic fiberreinforcedcomposites are widely used because of their greater strength and stiffness. But synthetic fibers are expensive and not ecofriendly. So, of late biofibers are replacing synthetic fibers which are extensively used as reinforcements in composites and these materials are gaining popularity as potential structural materials because they are abundantly available, renewable, sustainable, light weight, non abrasive, biodegradable, economical and ecofriendly. In spite of these positive points, natural fibers as reinforcements suffer certain drawbacks. Natural fibers are hydrophilic in nature due to the presence of hydroxyl groups which increases moisture sensitivity, where as matrix material is hydrophobic in nature. This leads to poor interfacial adhesion between fiber and matrix. The main role
surface modification of natural fiber can increase the interfacial fiber-matrix bonding [ 7 ] . In this paper, the purpose of the study is to develop a new retrofitting material which is Abacafiber for URM houses in view of mechanical aspects and also social aspects. Abacafiber is known as one of the strongest natural fibers, native to the Philippines and widely distributed in the humid tropics countries including Indonesia. In the last years, natural fibers reinforcedcomposites have received high attention due to their low density, excellent thermal properties, low cost, biodegradability, availability, non-toxicity and absorbing CO2 during their growth [8-11].
Tensile strength, tensile modulus, flexural properties, impact properties and percentage of elongation of untreated and alkali-treated Roystonea regia natural fibre-reinforced epoxy composites were increased with increase in fibre content and are highest at 20% wt. fibre content. Alkali- treated fibre composites have shown superior tensile properties than untreated composites. A.S. Singha and Vijay Kumar Thakur (6) 2008 investigates the mechanicalproperties of new series of green composites involving Hibiscus sabdariffa fibre as a reinforcing material in urea– formaldehyde (UF) resin based polymer matrix. It was observed that mechanicalproperties such as tensile strength, compressive strength and wear resistance etc. of the urea–formaldehyde resin increases to considerable extent when reinforced with the fibre. Thermal (TGA/DTA/DTG) and morphological studies (SEM) of the resin and bio composites have also been carried out. Till now different authors were used different natural fibers for the characterisation of fiberreinforcedcomposites.
Based on Figure 6, the major fall of hardness value is represented with 60% of fibre and this value is decreased directly proportional with other different mixture percentages of filler and resin. Maximum value of hardness is achieved in the sample of 70% fibre while the average values for hardness are 23.0 for 70% and 22.5 for 60% fibre compare with the sample of 50% and 40% fibre of 11.9 and 8.6 respectively. Although this test is subjective in the determination of the mechanicalproperties of boards, however it can provide an indication of their physical strength.
During the last few years, natural fibers have received much more attention than ever before from the research community all over the world. These natural fibers offer a number of advantages over traditional synthetic fibers. In the present communication, a study on the synthesis and mechanicalproperties of new series of green composites involving Hemp (Cannabis Sativa L) and Abaca (Musa textilis) fiber as a reinforcing material in Epoxy resin based polymer matrix has been reported. Static mechanicalproperties of randomly oriented intimately mixed Hemp (Cannabis Sativa L) and Abaca (Musa textilis) fiberreinforced polymer composites such as flexural, Impact, hardness strength, water absorption properties etc, were investigated as a function of fiber loading as per ASTM standards. Initially Epoxy resin prepared was subjected to evaluation of its optimum mechanicalproperties. Then reinforcing of the resin with Hemp (Cannabis Sativa L) and Abaca (Musa textilis) fiber was accomplished in three different forms: particle size, short fiber and long fiber by employing optimized resin. Present work reveals that mechanicalproperties such as flexural, hardness, water absorption and etc of the epoxy resin increases to considerable extent when reinforced with the fiber.
ABSTRACT: The paper works describes the development of mechanical behaviour of bamboo fiberreinforced with various polymer composites such as epoxy, ureaformaldehyde resin, polyester, phenolic, polylactic acid, polypropylene, polyester, poly (butylene succinate) and different filler materials. The results shows that bamboo fiberreinforced with epoxy composites have show the better mechanicalproperties. By adding filler materials increases the results of mechanicalproperties.
Abstract: This work deals with fabrication and investigation of mechanicalproperties of natural fibres such as abaca and banana fibre and compares with the hybrid natural fibre composite. Tensile, flexural and impact strength of the composites are investigated in the process of mechanical characterisation. The Reinforcement material used is a by-product of epoxy resin namely Bisphenol-A . Hand lay-up technique is used to manufacture the composite and the fibre content is varied through volume fraction of upto 0.5. Glass fibre on top and bottom layers of the laminate improves it’s surface finish and adds up strength. The Natural fibre is sandwiched in intermediate layers with the glass fibre. It is found that Abaca-Glass composite is found to have better tensile strength than the other two combination and Abaca-Glass-Banana Hybrid Composite is found to have better Flexural strength and Impact value.
this paper was only confined to local use even when used in automobile. The reasons adduced to this was that, these fibercomposites are highly prone to moisture absorption with low impact strength compared to that of synthetic fibers hence, they were being used just for weight reduction and it low cost of purchasing. But recently, researchers had shown that if this fiber are pre-treated chemically and blended with each other like blending the bast and leaf fibers, the expected impact strength can be achieved and if impregnated in well blended matrix, the moisture resistance can be improved upon thus they can be used where structural applications becomes inevitable and this will further reduce or put to an end the use of the synthetic composites .
Figure 7 also shows the of fracture toughness J2027 (Brendon Chemical) specimens filled with varying weight percentages of E-spheres SLG. It was found that the fracture toughness is highest with the neat resin and was 14.74 MPa m . The value dropped to a low of 7.37 MPa m when the SLG by weight is 10%; after this the values varied from 8.08 to 8.81 MPa m as the percentage by weight of SLG increases from 15 to 25%. It then re-bounced back to 11.88 MPa at 35% particulate loading. Redjel found that the fracture toughness of pure phenolic resin was 1.51 MPa m ; the fracture toughness of neat resin by weight of SLG reinforced phenolic resin, PF/E-SHPERES (0%) in this study was 8.72 MPa m , which is 5.78 times the fracture toughness of pure phenolic resin, an increase of 478%. This may be due to the improved resin used (the work was carried out eleven years later) and better post-curing method of the composite as compared to that of Redjel. By and large, it can be concluded that as far as tensile properties and fracture toughness as well as cost were considered, the best percentage by weight of SLG in phenolic resin should be 7.5 % as shown in Figure 7. At this particulate loading, the yield strength, tensile strength, Young’s modulus and fracture toughness are 123 %, 100 %, 94 % and 71 % of the neat resin respectively; the cost would be reduced by 7%. The main drawback is the fracture toughness but for some applications like applications in electrical equipment, this will not matter much.
which necessitates an improvement over the conventional methods of composite engineering. Composite materials can be developed using various materials, where one material forms the matrix and another forms the reinforcement. The reinforcements may be either in form of particles or fibers. Most, synthetic fiber reinforcements are expensive and toxic, thus leading to the exploration of viable options, the most prominent being natural fibers. Natural and thus biodegradable fibers are safer and more readily available. There has been a proliferation of research into the development of natural fiberreinforced polymeric composites with the aim of replacing the more expensive synthetic fibers with the readily available natural fibers which are hitherto wastes and contribute to environmental pollution due to problems with disposal. The interest in using natural fibers in composite development is no doubt due to their light weight, nonabrasive, combustible, nontoxic, low cost and biodegradable properties. However, poor interfacial adhesion, low melting points and poor resistance to moisture absorption, make the use of natural fiberreinforcedcomposites less attractive. Pretreatments of the fiber can clean and chemically modify the surface, stop the moisture absorption process and increase the surface roughness . The use of these fibers as reinforcements in both thermoplastic and thermoset polymers give the twin benefits of solving disposal problem and cost effectiveness. Prominent among the natural fibers are animal fibers, specifically the hairs of mammals which contain structural proteins notably keratin that form an intricate network of intermediate filaments in the cytoplasm of epithelial cells, which fundamentally provides structural maintenance for cells and tissues. This gives them the ability to withstand various chemical and thermal treatments and an appreciable variety of physical and mechanical stresses without sustaining permanent damage [3-4]. Due to these advantages animal hair has proven to be an adequate reinforcement to thermoset and thermoplastic polymers. Re-examination of animal fibers, particularly, keratin-based fibers for composites development has manifested in quite a remarkable but not exhaustive number of investigations with encouraging results . Dwivedi et al.  used human hair fiber to reinforce polypropylene and documented a significant improvement in the mechanicalproperties of the developed composites; the work
The most important types of natural fibres used in composite materials are flax, hemp, jute, kenaf, and sisal due to their properties and availability. Jute is an important bast fibre with a number of advantages. Jute has high specific properties, low density, less abrasive behaviour to the processing equipment, good dimensional stability and harmlessness. Jute textile is a low cost eco-friendly product and is abundantly available, easy to transport and has superior drapability and moisture retention capacity. It is widely being used as a natural choice for plant mulching and rural road pavement construction. The biodegradable and low priced jute products merge with the soil after using providing nourishment to the soil. Being made of cellulose, on combustion, jute does not generate toxic gases. Due to jute’s low density combined with relatively stiff and strong behavior, the specific properties of jute fibre can compare to those of glass and some other fibres like polypropylene.
Laminates manufacturing was conducted by a wet lay-up hand laminating process overlapping 8 layers of flax balanced fabric and vinylester matrix, with a 24 h long cure at room temperature followed by a 3 h long post-cure at 100 ˚C. After curing, composites were characterized by a total ratio of lignocellulosic reinforcement of 57.3 % (in weight). After post- curing and cooling, the specimens were extracted out from the original laminate by diamond saw and tool machining. Half of the samples (dry) were prepared for flexural testing in dry conditions and the other half (conditioned) was subjected to the accelerated aging immerging them for 1000 h in 35 ppt salt water at 80 °C. This solution, prepared with 35 % g/L of NaCl, intends to represent the overall proportion of inorganic salts representative of ocean water (in accordance with ASTM D1141 ), but, for the sake of simplicity, without introducing each salt (as MgCl 2 , Na 2 SO 4 , …).
Hybrid composite materials are made by combining two or more different types of fibers in single matrix phase or single reinforcing phase with multiple matrix phases or multiple reinforcing and multiple matrix phases . Normally it contains a high modulus fiber when it combined with low modulus fiber it enhances the high strength. In addition the expensive of preparation of composite material is low. The mechanicalproperties of hybrid composites depend on the fiber length, fiber orientation, weight fraction of the reinforcement, interaction between fiber and matrix . Natural fiber as a reinforcement has recently attracted the scientists and researcher’s because of their advantages like high specific strength, light weight, low density, low cost, ecofriendly nature, fully biodegradable, abundantly available and renewable. Plant fibers have some disadvantages such as high moisture absorption and low thermal stability. Several natural fibers are available such as banana, coir, sisal, bamboo, hemp, cotton, jute, pineapple etc . These fibers are derived from plants; they are ligno cellulose in nature.
Natural fibers are becoming popular in recent times especially in composites sector because they have lot of advantages over traditional fibers in terms of low cost, low density, biodegradable and easily processed [1,2]. Natural fibers are mainly classified into plant fibers, animal fibers, and mineral fibers as shown in Figure 1. Most commonly, composite materials have a bulk phase, which is continuous, called the matrix, and one dispersed, noncontinuous, phase called the reinforcement, which is usually harder and stronger. The reinforcement material can be of fibers, particulates, or flakes. The concept of composites is that the bulk phase accepts the load over a large surface area and transfers it to the reinforcement, which being stiffer, increases the strength of the composite. In biocomposites, natural fiber act as reinforcement material and the matrix material can be of synthetic polymer or a biopolymer . Natural fibers are cheap, abundant, and renewable and can be produced at low cost in many parts of the developing world. They are strong and stiff, and due to their low densities, it has the potential to produce composites with similar specific properties to those of E-glass fibers .
The paper demonstrates the possibility of expressing each of the model parameters as a function of single variable that is stress ratio, maximum stress level, or a material-dependent constant. Glass fibre reinforced plastic (GFRP) with similar mechanical and geometrical properties to the multiyear spring, was designed, fabricated (hand-layup technique) and tested. Computer algorithm using C-language has been used for the design of constant cross-section leaf spring. In this paper, only a mono-leaf composite leaf spring with varying width and varying thickness is designed and manufactured. Computer algorithm using C-language has been used for the design of constant cross-section leaf spring. The results showed that a spring width decreases hyperbolically and thickness increases linearly from the spring eyes towards the axle seat. The fabrication of composite leaf spring from unidirectional GERP. Composite leaf spring was fabricated using wet filament winding technique. In the present work, the hand lay-up process was employed. The templates (mould die) were made from wood and plywood according to the desired profile obtained from the computer algorithm.
Glass fiber is a material that contains extremely fine fibers of glass. It is light in weight, extremely strong, and robust. It is formed when thin strands of silica glass are extruded into many fibers with small diameters. Its bulk strength and weight properties are also very favorable when compared to metals, and it can be easily formed using molding processes. The individual filaments are now bundled together in large numbers to provide a roving. They are then woven in a machine to produce woven roving. In general, it is used as a reinforcing agent for composites to form a very strong and light fiberreinforced polymer (FRP) composite material.
When the composite is immersed into the chemical solution such as acid, al- kali or salt solution, the solution penetrates through the matrix and separates out in micro-cracks. On the other hand, the degradation of the fiber/matrix interface is caused by the dehydration of the matrix and penetration of solutions through micro-cracks, crazes or similar voids in the matrix   . For Hammami and Al-Ghilani  the degradation takes place via 2 stages. In the first stage, matrix is attacked under the combined action of water diffusion and the pres- ence of H + . In the second stage the fiber itself is attacked and cracks appeared on
In this liquid state, polyester may be processed by numerous methods, including hand lay-up, vacuum bag molding, spray up and compression molded sheet molding compound, etc. In combination with certain fillers they can exhibit resistance to breakdown under electrical arc and tracking conditions, Isophthalic polyester resins exhibit higher thermal stability, dimensional stability and creep resistance. In general, for a fiber-reinforced resin system, the advantage of polyester is its low cost and its ability to be processed quickly.
Kenaf or its scientific name Hibiscus cannabinus L is a warm season annual fiber crop closely related to cotton and jute. Historically, kenaf has been used as a cordage crop to produce twine, rope and sackcloth. Nowadays, there are various new applications for kenaf including paper products, building materials, absorbents and animal feeds. In Malaysia, realizing the diverse possibilities of commercially exploitable derived products from kenaf, the National Kenaf Research and Development Program has been formed in an effort to develop kenaf as a possible new industrial crop for Malaysia. The government has allocated RM12 million for research and further development of the kenaf-based industry under the 9th Malaysia Plan (2006–2010) in recognition of kenaf as a commercially viable crop.
Place the mould on the table and apply a thin plastic sheet on the mould called „Mila film‟. Apply a thin layer of resin on the surface of the lower mould. Next place the first layer of glass fiber and use the roller to squeeze the excess resin. Apply the resin over the first layer of glass fiber and then place the second layer and again use the roller to squeeze the excess resin. Repeat the procedure with alternatively layers of glass fiber and resin mixture until all the glass fibers were finished (Fig. 1 and Fig.2) Curing