Critical Review on Chemical Treatment of Natural Fibers to Enhance Mechanical Properties of Bio Composites

Natural fiber centered polymer composites are getting the interest of many researchers because of its unique assets like low density, low cost, eco-friendly and recyclability. Development and emerging technologies have increased burden on the environmentalists, therefore many researchers are working on bringing such technologies for society which are eco-friendly and biodegradable. Extensive research work has been done on reinforcing various natural fibers in bioplastics and plastics in fabricating composites for varied applications; however, some of the inferior qualities of natural fibers like low melting point, high water absorption rate and lack of adhesion make them less attractive. Composites fabricated by reinforcing untreated fibers often show less mechanical properties; therefore, to enhance these properties, the treatment to natural fibers becomes necessary for achieving good interfacial strength between fibers and polymer matrix. Pretreatment of natural fibers can vary its physical and chemical properties by roughening the surface and increasing its hydrophobic nature. Through this review paper an emphasis on the treatment using some natural fibers like sisal, banana, jute, nettle, coir fiber and its effect on the mechanical strength of fabricated biocomposites has been presented. The Effect of fiber treatment on tribological behaviour of natural fiber composite has been also discussed. Two major areas in fiber modification; physical and chemical treatment have been extensively discussed in this article.