Kenaf fiber chemical composition

Natural fibers can be classified as seed fibers (such as cotton), bast fibers (like flax, hemp, jute, kenaf, ramie), hard fibers (like sisal), fi-uit fibers (like coir), and wood fibers. The chemical composition and dimensions of some common agro-fibers are presented in Table 5.21. The origin of wood fibers can be sawmill chips, sawdust, wood flour or powder, cutter shavings, pulp or wood residues. As binders for these fibers, both thermosetting (like phenolic, epoxy, polyester) resins and thermosetting matrices [such as polyethylene (LDPE, HDPE), polypropylene (PP), poly(vinyl chloride) (PVC), polystyrene (PS)j can be used. Thermoplastic composites are, however, less expensive to process than thermosetting composites, in addition to their ability to be manufactured into complex shapes. 

Chemical Composition of Kenaf Fiber (% Oven Dry Basis)... 

Research to develop jute and kenaf fiber thermoplastic alloys is based on first thermoplasti-cizing the fiber matrix as described above, followed by grafting of the modified fiber with a reactive thermoplastic. This type of composite has the thermoplastic bonded onto the jute or kenaf so there is only one continuous phase in the molecule. This is done in one of two ways. In one case, the matrix is reacted with maleic anhydride that results in a double bond in the grafted reacted molecule. This can then be used in vinyl-type additions or in free radical polymerization to either build a thermoplastic polymer or graft one onto the jute or kenaf backbone. In the second method, the matrix is reacted with a bonded chemical and then reacted with a low-molecular-weight thermoplastic that has been grafted with side-chain anhydride groups. 

For raw kenaf composites, the tensile strength decreased with an increase in fiber loading. As the filler load increased, the weak interfacial area between the filler and the matrix increased, which in turn decreased the tensile strength. In order to increase mechanical properties of the composites, kenaf was chemically treated using acrylonitrile. Due to the elimination of most of the hydroxyl groups in the treated kenaf, the interfacial bonding between the kenaf filler and the PP matrix increased in the resultant composites. This in turn increased the tensile strength of the 25% fiber loaded treated composites compared to PP matrix itself. 

Applications of Kenaf-Lignocellulosic Fiber in Polymer Blends 503 Table 22.2 Chemical composition of some common natural fibers [7, 11],... 

Table 22.5 Chemical composition of different fractions of kenaf fibers [31],...

H.P.S. Abdul Khahl, A.E IreanaYusra, A.H. Bhat, and M. Jawaid, Cell wall ultrastructure, anatomy, lignin distribution, and chemical composition of Malaysian cultivated kenaf fiber. Ind. Crops Prod. 31,113-121 (2010). 

The aim of this study was extraction of cellulose from kenaf fiber which is available in Malaysia and preparation of nanocellulose whiskers from extracted cellulose in controlled hydrolysis condition. Chemical composition, size of particles, morphology, crystallinity, and thermal analysis of cellulose whiskers were investigated. 

Natural fibers vary widely in chemical composition, stmcture, and dimension and are obtained from different parts of the plants. Natural fibers, such as jute, ramie, flax, kenaf, and hemp are obtained from the stem abaca, sisal, banana and pineapple from the leaf cotton, coir, and kapok from the seed grass, and reed fibers (com, rice, and wheat) [4]. Climatic conditions, age, and fiber extraction... 

Sreekumar et al. (2008) have reported the effect of fiber content in polyester composites and have reported 40% volume fraction to show maximum tensile strength. Sapuan et al. (2006) investigated the mechanical properties of woven banana fiber reinforced with epoxy composites. Tensile strength. Flexure, impact and fracture surface study of woven pseudo stem banana fiber reinforced with epoxy composites was reported and the chemical modification of kenaf fiber was carried out by Edeerozey et al. (2007). Anuar et al. (2011) studied the thermal... 

Raw kenaf bast fiber have to be mechanically processed because of the coarseness, brittleness and low cohesive of the fiber bundles. Carding of kenaf is used to further back up the fiber bundles after the chemical processing of kenaf fibers. Generally optimum tensile properties and Young s modulus are dictated by the volume of reinforcing fiber used for the composites. 

Industrial crops. Industrial crops are developed and grown to produce specific industrial chemicals or materials. Examples include kenaf and straws for fiber, and castor for ricinoleic acid. New transgenic crops are being developed that produce the desired chemicals as part of the plant composition, requiring only extraction and purification of the product. 

A number of reviews have been studied on the potential of natural fibers such as sisal, kenaf, hemp, flax, bamboo, and jute for the preparation of thermoplastic composites. In this work, however sisal fiber (SF) has been used as reinforcement due to easily availability and comparatively low cost. The xmtreated and treated SF-reinforced RPP composites have been prepared and investigated their thermal, mechanical, morphological, weathering and impact properties. An improved mechanical, thermal, and morphological property has been observed for chemical treated SF as well as clay loaded RPP. The analysis revealed that SF-reinforced RPP composites with enhanced properties can be successfully achieved which warrants to replace the synthetic fillers-based conventional thermoplastic composites. These SF-based RPP composites can be the material of choice in the field of aeronautic, automobiles, civil engineering, etc., due to its low cost, low density, non-toxicity, recyclability, acceptable strength, high specific properties, and minimum waste disposal problems. 

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