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Science !
Fibre reinforced polymer composites began with cellulose fibre in phenolics in 1908, later extending to urea and melamine, and reaching commodity status in the 1940s with glass fibre in unsaturated polyesters. From guitars, tennis racquets and cars to microlight aircrafts, electronic components and artificial joints, composites are finding use in diverse fields. Because of increasing environmental consciousness and demands of legislative authorities, the manufacture, use and removal of traditional composite structures, usually made of glass, carbon or aramid fibres being reinforced with epoxy, unsaturated polyester resins, polyurethanes or phenolics, are considered critically. The most important disadvantages of such composite materials is the problem of convenient removal after end of life time, as the components are closely interconnected, relatively stable and therefore difficult to separate and recycle. Government regulations and growing environmental awareness throughout the world have triggered a paradigm shift towards designing materials compatible with the environment. The natural and wood fibres derived from annually renewable resources, as reinforcing fibres in both thermoplastic and thermoset matrix composites provide positive environmental benefits with respect to ultimate disposability and raw material utilization. After decades of high-tech developments of artificial fibres like carbon, aramid and glass, it is remarkable that natural grown fibres have gained a renewed interest, especially as a glass fibre substitute in automotive industries. Fibres like jute, wood, flax, coir or hemp are cheep, have better stiffness per unit weight and have a lower impact on the environment. Although automotive takes the lead in the revival of natural fibres, applications are mainly restricted to upholstery applications where acoustic and thermal insulation, low cost and an environmental image are advantages. The consumption of natural fibre in the automotive industry in Europe which was 21300 ton in 1999 and 28300 ton is in the year 2000 shows the rapid increasing of natural fibre consumption. It was also reported that wood polymer composites account for a 300,000t/year market in USA for building and garden products and should more than double by 2005.Decking accounts for about 60% of the total and rest of for flooring etc. And natural fibre composites of thermoplastics and thermosets, are shortly to be approved by the US Federal Aviation Authority and the UK Civil Aviation Authority for aerospace applications. There is a renewed interest in the use of natural fibres which is also known as agro-based resources for composites. This resources includes wood, agricultural plants and residues, grasses, water plants, and a wide variety of waste agro-mass including recycled wood, paper, and paper products. Jute is one of the most common agro-fibres having better mechanical properties which is sometimes superior to glass fibres. The price for natural and wood fibres which are feasible for different applications varies a lot depending on the changed economy of the countries where such fibres are widely available. Jute is the so-called golden fibre from Bangladesh. Diversified uses of jute are therefore now essential to enable the jute industry to survive, and new outlets for the fibre are being sought in wider textile fields and other engineering applications beyond wrapping and packaging. |
