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Natural fibers such as sisal, jute, and curauá have lengths that allow the production of aligned specimens. In the case of sisal fiber, this length varies from 700 to 1100 mm, making it possible to manufacture composites with lengths that fit the dimensions provided for in specific standards such as ASTM D3039M. This work seeks to evaluate the mechanical resistance of a composite of natural Sisal fiber aligned 0° unidirectional in the form of a plate, making a comparison in the tension obtained with experimental data through the universal testing machine EMIC with the theoretical data applying the mixing rule. The methodology used to manufacture these plates was manual, which fits the proposal of using little equipment or technology to obtain these composite materials. On the occasion, glass plates and double-sided tape were used so that the fibers maintained their alignment and it was possible to manufacture them.

The use of natural materials from renewable sources has several advantages when compared with non-renewable materials. Among these, there are vegetable fibers and sisal fibers that highlight for its wide application. Natural fibers appear as an alternative reinforcement to synthetic fibers, reducing costs and showing results close to synthetic fibers. The use of fibers is still growing slowly, but is already used in internal components of popular cars, elevator aircraft and structural components of the shipbuilding industry. In this article were produced composites reinforced by sisal fibers under two conditions: in a form of chopped fiber at a random disposition, and long and aligned fibers. In the first condition, sisal fibers were chopped in a granulator mill with length varying between 5mm to 15mm and randomly arranged in the polymeric matrix. In the second condition, the sisal fibers were arranged in an orderly manner and aligned in one-way direction.

Composite materials are alternative materials that come rising fast at last decades. With a view to the use of lighter and stronger materials that can replace ferrous materials, arise composites reinforced by synthetic fibers. Moreover, natural fibers emerge as an alternative reinforcement for the synthetic fibers because they are costly. Thus the present study aims to evaluate the behavior of particulate composite reinforced by sisal fibers in the size of 15 mm emerged in fluids such as water, salt water, and lubricating oil. The specimens were made according to ASTM D638M and aging it period of sixty days. After two months, the specimens were subjected to tensile tests, and determined the tensile strength results and deformation of the maximum load and the modulus of elasticity. In general, it was observed a reduction in tensile strength of the particulate sisal composite when immersed into the lubricant oil.

There's an intense growth on the study and development of new materials in recent years, especially in the category of materials that are less harmful to the environment and, moreover, have a low production cost. Following this tendency, composites reinforced with natural fibers that can replace satisfactorily a wide variety of materials have been produced. This work aims to study the properties presented by aplateshaped composite when reinforced by a fiberglass blanket with jute/sisal fibers in different lengths, produced in accordance with ASTM D3039 standard. The composite was produced by hand-lay-up process overlapping jute, sisal and fiberglass layers impregnated with polyester resin, placed in a hydraulic press under a 500 kg load. Specimens in accordance with ASTM D3039 were extracted and tested according to its procedures.

Natural fibers have being used on manufacturing of composite materials for car components. Between natural fibers, sisal and piassava deserve special attention. These components can be exposed to many environmental conditions, for example humid and saline environments, present in littoral regions of coastal countries. This study aims to evaluate the effects of salt water on the properties of a polyester matrix composite material reinforced with piassava natural fibers; and for this, using cheap and easily accessible materials and equipment. The polymeric matrix used was terephthalic unsaturated polyester resin, the curing agent was MK (Butanox M-50), in proportion of 0.33% (v/v). The fiber used was piassava, obtained at the popular trade center in the city of Belém-PA, the fibers were acquired in natural environmental conditions and without treatments. These materials were used to create specimens in the ASTM D 638 M standard, which got under aging process in salt water.

The natural fibers presents an intense target of research by the scientific community, they're an interesting option of reinforcement for polymeric matrix composites, due to their good properties of tensile resistance and flexibility; also, their low cost, easy accessibility and biodegradable characteristic, motivates studies about their applicability on industry and materials science. The objective of this study is to manufacture plates shaped polyester matrix composite, reinforced by jute fiber and fiberglass blanket for tensile test. Results and discussion about the properties the reinforcements attributed for the composite are compared to others composite materials. The fibers were cut in length of 10 mm and 50 mm, and blankets of random organization were made of them. They were used as the only reinforce of the plate, or together with fiberglass blankets.

This work has the purpose to study the effects of aging in natural water on a composite material of polyester matrix reinforced with sisal fibers. The specimens were produced by manual methods, not requiring high technologic devices or being costly. The polyester matrix used was terephthalic unsaturated polyester resin, whose curing agent was MK (Butanox M-50), in proportion of 0,33% (v/v). The sisal fiber used was obtained at a popular trade center in the city of Belém-PA, the fibers were acquired in natural environmental conditions and without treatments. These materials were used to create specimens in the ASTM D 638M standard, which got under aging process after lining. The water absorption was measured by weighing the specimens during the aging. The samples were submitted for a tensile test after the aging time, evaluating how the process changes the properties of the composite.

The use of composite materials reinforced with natural fibers has been widely studied in recent research seen the availability of feedstock and mainly because the productions facility, low cost and because they are biodegradable. In order to expand the applications of composite materials, this paper proposed to develop hybrid laminar composites associating natural fibers as jute, sisal and curaua in an array of type resin polyester and compare them with commercial bumpers available on the market. The sisal and curaua fibers were manually cut into lengths of 50 mm and then were arranged and incorporated separately with the polyester resin and the jute fiber cut, as a blanket in length 400 × 400 mm2 adopting for that a simple and manual manufacture process. Finally, it was executed a tensile test in hybrid laminated, and then a comparative study of tensile properties of different laminated hybrid composites, jute-sisal, jute-curaua and between the results of the commercial bumpers.

The curauá fiber, a bromeliad (Ananas erectifolius LB Smith), is considered large in the Amazon region, its mechanical properties of high strength, low density - capable of giving lightness to the final product - and potential for recycling, is listed for replace the fiberglass used as reinforcement to the plastic in the manufacture of parts with reduced features and detailed, produced by injection molding process, such as cars panel buttons, knobs and hinges. The materials used for manufacturing the polymer composites were curauá fibers acquired commercially from Belém in nature form, and a matrix of polyester resin terephthalic unsaturated and pre-accelerated chosen from one of the proportions of 0.33% (v / v), 1.66% (v / v), 3.33% (v / v) and 5% (v / v) which was initially studied. In the manufacture of the composite resin was used in combination with curauá fibers with lengths of 10 mm and a mass fraction of 3.87%, 4.87% and 5.87%.

The banana is among the most economically important crops for tropical and subtropical countries, where they have currently having great use in craft production, but it has been studied by many researchers to turn it into a high quality material for engineering. The extraction of the fibers of the banana pseudostem was done manually and without any chemical treatment. The fibers used in this study were drawn from the middle region of the pseudostem (trunk) of São-Tomé banana. They were characterized for their tensile strength, diameter, density and moisture content. The materials used for manufacture of polymeric composites were banana fibers, manually extracted from the pseudostem of São-Tomé banana (Musa sapientum, Musaceae), and an array of resin tereftálica unsaturated polyester and pre-accelerated chosen from the proportions of a 0.33% (v / v) 1.66% (v / v) 3.33% (v / v) and 5% (v / v) which was initially studied.

The use of composites as engineering materials have gained more space in various sectors of human activity. For these materials enable a good synergy between the various components that constitute it, resulting in a range of properties inherent to the material more convenient than the individual components. The strengthening of these composite materials, plant fibers have advantages compared to synthetic fibers because they are abundant, are biodegradable by biological processes, renewable and recyclable. In this paper, polyester matrix composites reinforced by short bamboo fibers arranged randomly were produced, using the lowest possible level of technological processes in production stages. The matrix used was polyester terephthalic pre-accelerated with cobalt naphthenate and cured at room temperature peroxide, methyl ethyl ketone (MEK) in proportion to the resin of 0,33% by volume. The bamboo fibers used were extracted from the campus - Belém of Federal University of Pará.

The use of natural fibers in composite materials of plant origin involves environmental, social and economic factors that must be met. Moreover, there is a shortage of progressive energy and mineral resources in general. Leading the search for renewable raw materials and low cost, which has been the factor of significant importance in directing research involving the use of natural fibers in composites. The paper presents polyester matrix composites reinforced by short sisal fibers, randomly arranged in the mold without using technological stages of production. The resin used was polyester terephthalic pre-accelerated in relation curing agent/resin of 0,33% by volume. The sisal fibers were acquired in the local market of Belem of Para. The fibers were manually cut in lengths of 5, 10 and 15 mm, untreated and at room temperature. The fibers were characterized mechanical, physically and microstructurally.

Maintenance of oil and gas pipelines presenting corrosion damage can be done following conventional routes as cutting and substitution of the damage parts or double sleeve welded method. Recently, the use of composite materials for repair of damaged pipelines is increasing due to the advantages presented by this process like the ease application and the possibility of performing the repair without interrupting the use of the line. As the pipe operates under hydrostatic pressure, it is important to make a stress analysis in order to know the stresses transferred to the composite material repair. In the present work, a microstructural and mechanical characterization of two composite materials used in pipe repair is made. One of the composites is made of continuous fiber glass and the other of a fiber glass fabric, both with polymeric matrix. The first was pulltruded and the second was processed by hand lay up.

This work presente a type of composite material that can be used in the manufacture or repair of ducts in draining of petroleum and derivatives. The characterization of microstructures, identification of the type of matrix and volumetric fraction of the composite material are presented. The composite material was submitted the aging in petroleum for a maximum period of 30 days in the temperature of 60°C and atmospheric pressure. The microstructural characterization was effected before and after the procedure of aging in petroleum. The composite material used has polyester matrix and continuous fiberglass and lined. The microstructure after the aging indicated the absorption of petroleum for the composite material, mainly for infiltration through the surface and porosities and for the interface between fiber and matrix. Also, curve of absorption of petroleum in function of the time is presented.

This work presents a study about the production of composites of matrix polymeric reinforced with natural fibers incorporate through pré-pregs and sheets. The studied fibers were curauá, sisal, côco, palha da costa and a woven composed of mallow fibers and jute. The fibers were rehearsed in traction uniaxial and your certain resistance. The pré-pregs were manufactured by pulverization of the polymeric on the fibers that were previously arrested and aligned; the sheets were already produced being drained the resin on the fibers. Composites were manufactured reinforced with the sisal fibers, woven mallow-jute and a composition hybrid sisal/woven mallow-jute and rehearsed by bending in three points. For visual inspection it was verified that the pré-pregs were shown more suitable for the composition of composites.