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Recent Development of Fiber Reinforced Composite Materials

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Recent Development of Fiber Reinforced Composite Materials See discussions, stats, and author profiles for this publication at: http://www.researchgate.net/publication/263351638 Recent Development of Fiber Reinforced Composite Materials CHAPTER · JULY 2014 DOWNLOADS VIEWS 260 51 2 AUTHORS: Himadri Das North Eastern Regional Institute o… 6 PUBLICATIONS 0 CITATIONS SEE PROFILE Dipul Kalita CSIR-North East Institute of Scienc… 17 PUBLICATIONS 62 CITATIONS SEE PROFILE Available from: Dipul Kalita Retrieved on: 21 July 2015 13 Recent Development of Fiber Reinforced Composite Materials Himadri Das and Dipul Kalita* CSIR- North East Institute of Science and Technology, Assam, India Abstract Natural fi bers such as jute, coir, sisal, pineapple, ramie, bamboo, banana, etc., have been the focus in the development of natural fi ber composites; primarily in value added application. Th e versatile material system so developed has potential for wood substitute applications like door shutters, fl ooring tiles, roofi ng sheets, parti- tions, etc., and is envisaged to signifi cantly contribute towards forest conservation and environmental protection. Polyester resin of fi re retardant grade was used for preparing the composite. In the polymerization process, cobalt naphthonate and methyl ethyl ketone peroxide (MEKP) as catalyst were used. Th e study reveals that the developed polymer–natural fi ber–industrial (inorganic) wastes (fl y ash, red mud) composites attain far superior mechanical properties and resistance to abrasive wear, fi re, water absorption, weathering and chemical attack, as compared to their conventional counterparts such as wood, medium density fi ber (MDF) boards, particle boards, etc. Relevant engineering properties such as physical and mechanical resistance to abrasive wear, weathering, fi re, etc., of the plant fi ber-rein- forced polymer matrix composites so synthesized were characterized. Th e eff ects of fi ber content, matrix type and interfacial bonding on the tensile and fl exural properties of these composite materials have been determined through extensive testing at diff erent conditions. Th e mechanical properties of natural fi bers were improved by using a chemical treatment process and improved the mechanical properties of composite materials. Shrinkage of fi bers during this process has sig- nifi cant eff ects on the fi ber structure, as well as on the mechanical fi ber properties, such as tensile strength and modulus. Th e tensile strength, initial modulus and elongation at break were evaluated for untreated and treated fi bers. One of the cur- rent studies, which focused on thermoplastics, utilizing natural fi ber compounded with a thermoplastic resin (polyethylene, polypropylene, PVC, etc.), has yielded *Corresponding author: [email protected]; [email protected] Ashutosh Tiwari and Anthony P.F. Turner (eds.) Biosensors Nanotechnology, (441–496) 2014 © Scrivener Publishing LLC 441 442 Biosensors Nanotechnology excellent wood substitute. Th e development of green reinforced composites for a wide range of applications is also a recent trend. Th ere have been eff orts to develop new pathways to produce natural polymers with better mechanical properties and thermal stability using nanotechnology; and to use natural polymers to make bio- degradable plastics and their composites with lignocellulosic fi bers. In the pro- duction of composite board, phenol formaldehyde and urea formaldehyde are the most used thermosetting resins and many researchers have produced particle boards from lignocellulosic materials. Th e suitability of particle board for interior and exterior use is based on the water absorption and swelling in water. From the increase in mass and dimensions, the percent water absorption and percent swell- ing along surface and thickness were calculated. Board prepared with a mixture of UF and PF resins in diff erent proportions gave variable MOR and water absorp- tion properties. Studies strongly suggest that newly developed plant fi ber or indus- trial waste-reinforced polymer composite materials are quite capable of serving as a potential cost and energy eff ective, technologically viable and attractive option to conventionally used wood and other identical materials. Th is chapter includes an overview of the developments made in the area of fi ber reinforced composites, in terms of market, processing methods, matrix-reinforcement systems, morphol- ogy, properties and product development. Some critical issues and future works are also discussed. Keywords: Medium density fi ber (MDF), MOR, UF and PF resins, matrix- reinforcement 13.1 Introduction Th ree-thousand years ago natural fi bers were used for the fi rst time in composite systems in ancient Egypt, where straw and clay were mixed together to build walls. Over the last decade, polymer composites rein- forced with natural fi bers have received ever-increasing attention, both from the academic world and from various industries. Th ere are a wide variety of diff erent natural fi bers which can be applied as reinforcement or fi llers. Increased environmental consciousness throughout the world has developed an increasing interest in natural fi bers and their applications in various fi elds. Natural fi bers are now considered an important fi eld. Environmental and economical concerns are stimulating research in the development of new materials for construction, furniture, packaging and automotive industries. Particularly attractive are the new materials, a good part of which are based on natural renewable resources, thereby preventing further stresses on the environment caused by the depletion of dwindling wood resources from forests. Examples of such raw material sources are annual growth native crops plant fi bers, which are abundantly available Recent Development of Fiber Reinforced Composite Materials 443 in tropical regions. Th ese plant fi bers (like jute and sisal) have been used for hundreds of years for many applications such as in ropes, beds, bags, etc. If new uses of fast growing, native plants can be developed for high- value, non-timber-based materials, there is a tremendous potential for cre- ating jobs in the rural sector. Th ese renewable, non-timber-based materials could reduce the use of traditional materials such as wood, minerals and plastics for some applications. Research on natural fi ber composites has existed since the early 1900s but has not received much attention until late in the 1980s. Composites, primarily glass but including natural reinforced composites, are found in countless consumer products including boats, skis, agricultural machinery and cars [1–3]. A major goal of natural fi ber composites is to lessen the need to use expensive glass fi ber ($3.25/kg), which has a relatively high density (2.5 g/cm3) and is dependent on nonrenewable sources [1, 3]. Plant waste fi bers can be described as lignocellulosic, i.e., resources com- prised primarily of cellulose, hemicelluloses and lignin. Lignocellulosics include wood, agricultural residues, water plants, grasses and other plant substances [4]. In the building materials industry, the “term” composite is oft en used in a board sense to describe woody materials bonded together by adhesives covering the entire gamut of plywood, oriented strand board, wafer board, fi ber board and other types of paneling products. Such nat- ural fi ber thermoplastic composites fi nd a wide array of applications in the building and construction industry such as door and window frames, decking material, railings for parapet wall systems, furniture sections (park benches, etc.) and others. Th ese can also cater to a number of industrial applications. All such products are fabricated by extrusion through prop- erly designed dies. Th ermoplastic composite is consistent and uniform in properties due to intimate compounding of resin and natural and natu- ral fi ber/ fi ller. While positioned against wood, they score much better in terms of dimensional stability, no water absorption and hence, no swelling in moist weather, better fungal resistance, reduced thermal linear expan- sion, etc. Th e workability of the composite is also quite good in terms of its ability to be sawn and nailed or screwed by conventional methods. Plant waste fi bers have the composition, properties and structure that make them suitable for uses such as composite, textile and pulp and paper manufacture. Biomass, including agricultural crops and residues, forest resources and residues, animal and municipal wastes, is the largest source for cellulose in the world. Organic plant waste such as oil palm, pineapple, banana and coconut fi ber are annually renewable, available in abundance and of limited value at present. Th ese lignocellulosic by-products could be a principle source for fi bers, chemicals and other industrial products [5]. 444 Biosensors Nanotechnology Th e use of natural fi bers as reinforcing materials in both thermoplastics and thermoset matrix composites provides positive environmental ben- efi ts with respect to ultimate disposability and best utilization of raw mate- rials [6, 7]. Natural fi ber-reinforced resin matrix composites have to overcome many challenges in order to be commonly used as engineering materials. A common drawback of these composites is the large variability of their mechanical properties, in many instances associated with low mean val- ues for their properties [8, 9]. Th ese characteristics are due to the intrin- sic variability of the properties of the fi bers, the susceptibility of natural fi bers against moisture, and poor wetting
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