Development and characterization of fire retardant nanofiller from date palm biomass

To achieve a green composite product with large range of potential applications, industries are developing nano-sized fillers from biomass material. In the present work, the potentiality of utilizing date palm trunk fiber, as agricultural waste for the development of fire retardant nano-filler, was investigated. Two different nanofiller products (Nanofiller-55 and Nanofiller-99) were prepared from the date palm–derived microfiller through combined chemical process and high-energy ball milling. Characterization was conducted for the produced nanofiller as well as microfiller, through advanced testing analysis. From morphology examination, the nanofiller was revealed as individually dispersed nanoparticles in rectangular-like shape under transmission electron microscopy (TEM). Meanwhile, the field emission scanning electron microscopy (FESEM) presented the nanofiller particles in irregular shapes with rough surface after the breakdown of compact microfiller structure by ball milling process. The particle size analysis also proved that small nanoparticles in the mean size range of 274.5–289.7 nm were generated for both Nanofiller-55 and Nanofiller-99 samples. Furthermore, energy-dispersive X-ray (EDX) analysis presented the presence of carbon and oxygen as the major fiber elements in nanofillers, while the residual silica, sulfur, calcium, potassium elements were detected to decrease after combined treatment process. Additionally, the physico-chemical analysis revealed those nanofillers possessed great crystallinity between 58 and 67%, which could impart them as strong load-bearing agent. As for thermal analysis, both Nanofiller-55 and Nanofiller-99 samples exhibited high decomposition temperature, while showing stable degradation behavior with enhanced heat resistance. Thus, the produced nanofillers in this work can be used as fire retardant material for nanocomposites fabrication in the future.