This chapter mainly describes the theory and research which have been defined and done by various researcher years ago. Related information from previous studies is extracted as references and discussion based on their research.
2.1 Natural Fibers and Classification
Natural fibers have attracted the attention of scientists and technologists because of the advantages that these fibers provide over conventional materials. These natural fibers are low-cost fibers with low density and high specific properties. Unlike other materials, they are biodegradable, nonabrasive and readily available. The tendency to form aggregates during processing and poor resistance to moisture is the factor that becomes a barrier for the natural fibers to be used commercially in the manufacturing sector. Natural fibers are low cost, recyclable, low density and eco-friendly material. Their tensile properties are very good. The utilization of natural fibers in the industrial application provides challenges for the researcher to develop suitable techniques to obtain good quality fibers for use as reinforcement for polymer composites (Wambua et. al., 2003).
Kenaf (Hibiscus cannabinus L.) is an herbaceous annual spring crop belongs to the Malvaceace family and section Furcaria. The genus of Hibiscus is widespread including some 400 species. Kenaf is closely related to cotton, okra, hollyhock, and roselle. It is a fast-growing plant that can grow to a height of 4-5m in about 4-5 months growing season with the kenaf stalk diameter of 25-35mm (Li & Mai, 2006).
Kenaf is cultivated for probably as early as long (4000 BC) (Roseberg, 1996) and its origin is from Africa. Although kenaf originated from Africa, its production in Africa is very low. In 2010, the total production in Africa was just 3% of the world production. Currently, more countries pay more attention to kenaf research and its cultivation. Over than 20 countries mainly in China, India, Thailand, and Vietnam had commercialized kenaf cultivation. In 2010, India has been recognized as a top producer of kenaf with 140 000 MT, followed by China (75 000 MT) and Thailand (18 000 MT) (IJSG, 2012). In Malaysia, it was first introduced in the early 1970s and was highlighted in the late 1990s as an alternative and cheaper source of materials choices. Kenaf also planted in Malaysia as an alternative crop to tobacco in the medium and long-term. Figure 2.1 shows kenaf tree.