Nur Farhani Ismail

Kenaf-Biocomposites: Manufacturing, Characterization, and Applications

Given the environmental issues faced by the industry, the development of engineering products from natural resources has increased worldwide. The increasing demand for cost and weight reduction can be attained by sustainable manufacturing techniques. Kenaf plants are natural resources, which show high performance compared with other natural fibers. Kenaf fibers can be modified by physical and chemical methods. Kenaf polymer composites are fabricated via processing technologies based on thermoforming, thermoplastics, and thermosets. Thermoplastic processes, such as compression molding, pultrusion, extrusion, and solution blending, have been adapted but are limited to two-dimensional structures based on polymer composites. However, the thermoset processes include sheet molding and resin transfer molding techniques, which were also employed for the fabrication of kenaf polymer composites. Most of the recent work discussed Kenaf-Reinforced Composites (KRCs) prepared by compression molding. However, resin transfer molding has received attention because of its versatility. This chapter aimed to highlight and explore advance research related to the fabrication of kenaf polymer composites by various routes, as well as their physical and mechanical properties. A brief description of KRCs with different additives, fiber loadings, treatment, and polymers is also discussed. Furthermore, these KRCs with versatile mechanical properties may be used for construction, building materials, animal beds, corrosion resistance, marine, electrical, transportation, and automotive applications.

Tensile Properties of Unidirectional Kenaf Polypropylene Composite at Various Temperatures and Orientations

The development of bio-composites as biodegradable and renewable materials for sustainable technology are advantageous in creating a green and healthy environment. However, the application of natural fiber as a bio-composite material have been found to be restricted especially as it has lower thermal resistance in comparison to synthetic fiber. Therefore, the objective of this study is to investigate the influence of fiber orientations on the tensile properties at various tensile temperatures for unidirectional kenaf polypropylene (PP) composite. Samples were prepared by hot pressing process. In this study, kenaf long fibers that are produced from water retting process is use as a reinforcement agent while PP as a polymer in the composite fabrication. A tensile test was carried out at different temperatures (30°C, 60°C, 90°C, 120°C) for various orientations (0°, 45° and 90°). It was found that an increase of temperature will reduce the modulus and tensile strength where the highest reduction occurred between 60°C to 120°C and most significantly on the orientation of 45° and 90°, which is lower than pure PP. This concludes that the application of kenaf PP composite is optimum between room temperature with a cut-off temperature at 60°C.

Unidirectional Kenaf Polypropylene Composites: Optimization Process by Two Level Full Factorial

The interest of using kenaf fibers in composite fabrication has grown due to renewable, sustainable and environmental issues. The applications of kenaf composite have been broadly exploited especially in automotive industry. In this research, unidirectional kenaf polypropylene (PP) composites were prepared using the hot pressing method. The processing parameter need to be optimized to ensure that the fabrication process will enhance the mechanical properties of the composite. Thus, a research on the optimization process on the processing parameter (temperature, pressure, pressing time and kenaf percentage) on the tensile properties was conducted by using a two-level full factorial design. The effect of the individual factors and their interaction were observed. From statistical analysis, the main effect of tensile strength and young modulus is the percentage of kenaf fibers with 21.67% contribution. The interaction between kenaf percentage and pressing time also contribute an effect on the tensile properties with 13.29% contribution. Finally, the result showed that at 190°C, pressure 5 MPa, 5 minutes pressing time and 50% fiber content will give the optimum tensile strength and young modulus which is 163.12 MPa and 11.17 GPa respectively with improvement of 486% tensile strength compared to pure PP.