Study on The Characteristics of NaCl Treated Kenaf Fiber Epoxy Composite Board

The treatment of kenaf fiber surfaces with chemicals has proven to be an effective method to improve composite properties. Meanwhile, natrium chloride (NaCl) is one of the chemicals that has great potential to be used for modifying natural fibers. Therefore, this study aims to investigate the characteristics of a composite board made from NaCl-treated kenaf fiber and epoxy. The method used was a completely randomized design with two factors, namely the level of NaCl in the treatment solution including 1, 3, and 5%wt, as well as the epoxy content of 10, 20, and 30%wt based on the dry weight fiber. The NaCl treatment was carried out by soaking the fibers in the solution for 1 hour at room temperature, rinsed using water until the pH of the water reached 7, and then dried in an oven at 80ᵒC for 6 hours. Furthermore, the Kenaf fiber and epoxy were mixed manually, while the boards were manufactured using a heat pressing system at 120ᵒC, with a pressure of 3.5 MPa for 10 minutes, and a thickness of 10 mm. The physical and mechanical properties were then evaluated based on JIS A5908. The results showed that the composite board properties were optimum at NaCl 5%, 20% of epoxy, modulus of elasticity and rupture of 2.02 GPa, and 18.63 MPa respectively, internal bonding 1.94 MPa, thickness swelling 2.89 %, and water absorption of 10.49%. The results showed that the physical and mechanical properties of the composite board increased with a high NaCl concentration.

The Effect of UV Irradiation on Tensile Strength of Polypropylene Reinforced Kenaf Fiber and Peat Soil

Nowadays, natural fiber polymer composites have been widely used in many industries and applications because of their low cost, renewable and eco–friendly. However, exposing this material to the outdoor environment will affect the material properties as it is exposed to various situations such as ultraviolet exposure, raining, etc. This paper studies the degradation of kenaf fiber, polypropylene strengthened with peat soil combustion at 600ºC upon ultraviolet exposure. The wood–plastic composites (WPCs) produced into two batches, kenaf fiber mixing with polypropylene and kenaf fiber and peat soil mixing with polypropylene. All the specimen has exposed in ultraviolet (UV) irradiation at 0 hour, 100 hours, and 200 hours, respectively. The UV irradiation accelerated weathering tester machine was conducting the water spray cycle, which is 4 hours of water spray and 8 hours without water spray continuously until achieved the target time. The finding obtained from the tensile test, the composition with the highest contain of kenaf fiber in a polymer composite, has the lowest tensile strength after exposed with 200 hours of UV irradiation, which is 20.23 MPa. While the adding peat soil as reinforcement has shown the increasing the percentage of tensile strength after 200 UV exposure.

Physical, Mechanical, and Morphological Properties of Hybrid Cyrtostachys renda/Kenaf Fiber Reinforced with Multi-Walled Carbon Nanotubes (MWCNT)-Phenolic Composites

Adequate awareness of sustainable materials and eco-legislation have inspired researchers to identify alternative sustainable and green composites for synthetic fiber-reinforced polymer composites in the automotive and aircraft industries. This research focused on investigating the physical, mechanical, and morphological properties of different hybrid Cyrtostachys renda (CR)/kenaf fiber (K) (10C:0K, 7C:3K, 5C:5K, 3C:7K, 0C:10K) reinforced with 0.5 wt% MWCNT–phenolic composites. We incorporated 0.5 wt% of MWCNT into phenolic resin (powder) using a ball milling process for 25 h to achieve homogeneous distribution. The results revealed that CR fiber composites showed higher voids content (12.23%) than pure kenaf fiber composites (6.57%). CR fiber phenolic composite was more stable to the swelling tendency, resulting in the lowest percentage of swelling rate (4.11%) compared to kenaf composite (5.29%). The addition of kenaf fiber into CR composites had improved the tensile, flexural, and impact properties. The highest tensile and flexural properties were found for weight fraction of CR and kenaf fiber at 5C:5K (47.96 MPa) and 3C:7K (90.89 MPa) composites, respectively. In contrast, the highest impact properties were obtained for 0C:10K composites (9.56 kJ/m2). Based on the FE-SEM image, the CR fiber lumen was larger in comparison to kenaf fiber. The lumen of CR fiber was attributed to higher void and water absorption, lower mechanical properties compared to kenaf fiber. 5C:5K composite was selected as an optimal hybrid composite, based on the TOPSIS method. This hybrid composite can be used as an interior component (non-load-bearing structures) in the aviation and automotive sectors.