Natural fiber composites properties

Several of these natural fiber composites reach the mechanical properties of glass fiber composites, they are already being used in the automobile and furniture industries. Up to now, the most important natural fibers were jute, flax, and coir. 

Until 2008, there was an explosive growth in wood and natural fiber composites in the United States. Because of the crisis in the building-products market, the demand for these composites dropped sharply. However, it is expected that economics, environmental concerns, and improved properties in the coming years will increase the demand for natural fiber composites. 

A. K. Bledzki, S. Reihmane, and J. Gassan, Properties and modification methods for vegetable fibers for natural fiber composites, J. Appl. Polym. Sci., 59 (1998) 1329-1336. 

As an extension to the considerable amount of research undertaken on processing and properties of natural filler composites, in this last decade, a number of researchers have explored the concept of namral filler-reinforced PLA composites. An outstanding one is the project FAlR-CT-98-3919 (New ftmctional biopolymer-natural fiber composites from agriculture resources) by European Union, in which one of the key objectives was to manufacture demonstration parts on a pre-competitive level with the automotive industry as the main potential market. Within this project, Lanzillotta et al. [21] prepared biocomposites with flax fibers and PLA as the biopolymer matrix. The research focused on the idea of converting biocomposites into products for real automotive applications. 

Kim, S.J. Moon, J.B. Kim, G.H. Ha, C.S. (2008). Mechanical Properties of Polypropylene/Natural Fiber Composites Comparison of Wood Fiber and Cotton Fiber. Polymer Testing, Vol.27, No. 7, (October 2008), pp. 801-806, ISSN 0142-9418 Kotek, J. Kelnar, L Studenovsky, M. Baldrian J. (2005). Chlorosulfonated polypropylene preparation and its application as a coupling agent in polypropylene-clay nanocomposites. Polymer, Vol. 46, No. 16, (June 2005), pp. 4876-4881, ISSN 0032-3861... 

Rowell R.M., Property enhanced natural fiber composite materials based on chemical modification, in Science and Technology of Polymers and Advanced Materials Emerging Technologies and Business Opportunities, Proceedings of the Fourth International Conference on Frontiers of Polymers and Advanced Materials, Cairo, Egypt, 4—9 January 1997), Plenum Press, New York N.Y., 1998, pp. 717-732. 

Composite materials are combinations of two or more materials with different, often complementary properties (Cheremisinoff 1997). Polymeric natural fiber composites have traditionally been manufactured using short reinforcement fibers dispersed in a matrix (Van de Velde and Kiekens 2001) or compression molded from a nonwoven textile (Mueller and Krobjilowski 2003). These applications usually contain low fiber volume fractions and lack control of fiber angles, resulting in their primary use as nonload carrying components (Svensson 1997). The role of stiff and strong reinforcing fibers in a composite is to carry the load and improve mechanical properties of the matrix material. Regardless of fiber type (carbon. 

Lei Y, Wu Q, Yao F, Xu Y (2007) Preparation and properties of recycled HDPE/natural fiber composites. Composites 38 1664-1674... 

Kim SJ, Moon JB, Kim GH, Ha CS (2008) Mechanical properties of polypropylene/natural fiber composites comparison of wood fiber and cotton fiber. Polym Test 27 801-806... 

One of the most important focus areas of research in the development of natural fiber-reinforced polymer composites is characterisation of the fiber-matrix interface, since the interface alone can have a significant impact on the mechanical performance of the resulting composite materials, in terms of the strength and toughness. The properties of all heterogeneous materials are determined by component properties, composition, structure and interfacial interactions [62]. There have been a variety of methods used to characterize interfacial properties in natural fiber-reinforced polymer composites, however, the exact mechanism of the interaction between the natural fiber and the polymeric matrix has not been clearly studied on a fundamental level and is presently the major drawback for widespread utilization of such materials. The extent of interfacial adhesion in natural fiber-reinforced polymer composites utilizing PLA as the polymer matrix has been the subject of several recent investigations, hence the focus in this section will be on PLA-based natural fiber composites. 

P.K. Bajpai, I. Singh, and J. Madaan, Joining of natural fiber reinforced composites using microwave energy Experimental and finite element study. Mater. Des. 35, 596-602 (2012). P. K. Bajpai, I. Singh, and J. Madaan, Comparative studies of mechanical and morphological properties of polylactic acid and polypropylene based natural fiber composites. Reinf. Plast. Compos. 31, 1712-1724 (2012). 

A. Shahzad, Impact and Fatigue Properties of Natural Fiber Composites, Swansea University, Swansea, Ph. D. thesis (2009). 

As the performance of the composite is profoxmdly dominated by the micromechanical deformation process, its knowledge and control are critical for the improvement of composite properties. The effect of particle characteristics and interfacial adhesion on the micromechanical deformation processes in PP-wood composites was investigated by Renner et al. [7]. They proposed a failure map as well as the practical results and considered the influence of matrix characteristics on deformation and failure in PP-natural fiber composites in other research [24]. Hietala et al. [78] studied the effect of chemical pre-treatment and moisture content of wood chips on the wood particle aspect ratio during the processing and mechanical properties of WPCs. The use of pretreated wood chips enhanced the flexural properties of the wood chip-PP composites. Moreover, the use of undried wood chips compared to dried one can improve and reduce the flexural strength and flexural modulus, respectively. On the other hand, they concluded that the use of pretreated and undried wood chips lead to the highest aspect ratio after compounding. The effect of composition and the incorporation... 

Polymers reinforced with cellulose fibers have received much attention in recent years because of their low density, nonabrasive, combustible, nontoxic, low cost and biodegradable properties. Several authors have reviewed recent advances in the use of natural fibers in composites like flax [ 1 ], jute [2,3], straw [4], kenaf [5,6], coir [7-9], fique [10], among others. Natural fibers have been used to reinforce thermoplastics and thermosets polymers in automotive and aerospace applications [11]. The influence of surface treatments of natural fibers on interfadal characteristics was also studied [12-17], and Joshi et al. [18] compared the life-cycle environmental performance of natural fiber composites with glass fiber composites. In this study, natural fiber composites were found to be environmentally superior in most applications. 

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