Investigation of the effect of nanoparticles on the acoustic and flammability behavior of natural kenaf fibers

The use of natural kenaf fibers as a green and sustainable material and due to its remarkable properties is known as a potential alternative to synthetic fibers in the composite industries. One of the effective approaches to improve the properties of these fibers, especially in the face of fire, is creating a nano-coating with inorganic materials on the surface of the fibers. In this regard, this study was conducted with the aim of improving the flammability and acoustic properties of natural kenaf fibers using mineral nanoparticles.

The present study is a cross-sectional experimental study on a laboratory scale. Synthesis of ZnO-TiO2 nanoparticles was by co-precipitation method and its properties were determined using X-ray diffraction (XRD), Energy-dispersive X-ray spectroscopy (EDX) and scanning electron microscopy (SEM) analyzes.   In this study, the flame retardant performance by conical calorimeter, and the study of acoustic absorption (at normal angles) in order to investigate the acoustic behavior of natural fibers was tested by impedance tube based on the transfer function method and ISO10534-2 standard.

Based on the results, the time to ignition (TTI) in the fibers with ZnO-TiO2 coating was almost doubled compared to the raw fibers. The total burning time of nanoparticle-coated fibers increases from 471 to 870 seconds, and the amount of carbon dioxide production in raw fibers with ZnO-TiO2 nanoparticles has decreased from 0.33 to 0.12. Also, this type of fiber had a higher sound absorption coefficient than raw fibers.

Due to the outstanding benefits of kenaf fibers (economic and environmental benefits) and the increasing use of these fibers as multifunctional composites, the process of coating these fibers with nanoparticles is considered a good approach to improve the thermal and acoustic properties.