All-lignocellulosic fiberboards from giant reed (Arundo donax L.): Effect of steam explosion pre-treatment on physical and mechanical properties

Steam explosion has proved to be one of the treatments which produces the best physical and mechanical results in the production of fiberboards without adding adhesives. Perhaps the main drawback is energy consumption, making process optimization essential. The aim of this study was to explore the effect of five severity (R0) levels of steam explosion pre-treatment on mechanical and physical properties of binderless fiberboards, made with giant reed (Arundo donax L.). Results showed that fiberboard properties significantly improve within a 5 degrees C range of pre-treatment temperature (Tr) and then get worse after exceeding the maximum Tr of 200 degrees C. Therefore, the best results were obtained for the 200 degrees C Tr and the average values were MOR 4538,50 N/mm2, MOE 34.67 N/ mm2, IB 4.079 N/mm2, TS 7.50%, and WA 9.13%. Scanning electron microscope (SEM) observation and Fouriertransform infrared (FT-IR) spectra analysis confirmed that major morphological and chemical changes occurred in the Tr range of 190-195 degrees C. Finally, by means of Thermogravimetric analysis (TGA), the limiting oxygen index (LOI) was calculated to derive information regarding the material's ability to be both flame retardant and selfextinguishing.