Development and evaluation of zinc oxide-blended kenaf fiber biocomposite for automotive applications

There is an increasing environmental concern of using glass-fiber sheet molding compound (GF-SMC) in automobiles. Here, a zinc oxide (ZnO) blended natural fiber-reinforced biocomposite (NFRBC) was developed and evaluated to replace the commercial automotive GF-SMC (Meridian's SLI 323IF) due to its superior properties and environmental friendliness. The NFRBC consists of kenaf (Hibiscus cannabinus) fibers blended with ZnO nanoparticles to obtain a fiber-mat preform used to manufacture the final NFRBC using a vacuum-assisted resin transfer molding process. Adding 12.4 % ZnO nanoparticles increased flexural strength (121 %), tensile strengths (38 %) and water resistance (76 %). The ZnO12.4 %-NFRBC had comparable mechanical properties as GF-SMC while the production consumed 9% less energy and reduced the environmental burden by 33 % from life-cycle assessment (LCA). Although the water-resistance of ZnO12.4 %-NFRBC was significantly improved, further adjustments are needed to fully meet the requirements for GF-SMC replacement.