Optimization of the Production Factors of Boards Obtained from Arundo donax L. Fibers without Added Adhesives

Abstract

The main objective of this work was to further analyze the optimization of the production factors of Arundo donax L. fiberboards obtained without adhesives. The production of boards derived from Arundo donax L. without added adhesives and with high mechanical performance has already been demonstrated. This present study explored a modification in the production process through a final curing thermal treatment (final heat treatment, FHT). Since pressing time is an influential factor in the production cost, it is expected that curing allows a reduction of this time. This study compared the results obtained by three panel-production alternatives: long pressing time (tp) without curing and long and short tp with FHT. Of the two factors analyzed, pressing pressure (Pp) was the most important production factor in both the modulus of elasticity (MOE) and modulus of rupture (MOR), while curing was the most important factor for the internal bond (IB). The study shows that a FHT facilitates the distribution of lignin and a possible improvement in the quantity and quality of bonds between lignin and cellulosic fibers. As a consequence, it improves the IB, produces boards with more homogeneous physical and mechanical properties and thereby makes them more hydrophobic. The curing thermal treatment allows high performance panels to be obtained in a manner which is more ecological, quicker, and cheaper.

Approaching Self-Bonded Medium Density Fiberboards Made by Mixing Steam Exploded Arundo donax L. and Wood Fibers: A Comparison with pMDI-Bonded Fiberboards on the Primary Properties of the Boards

“…Among the hydrothermal pre-treatments, steam explosion (STEX) has been used for years, as the Masonite process, in the production of fiberboards [ 35 ]. Hence, STEX already showed its applicability in this field, especially in the production of hardboards through wet processes, with many examples available in the literature, and applications with different materials such as residual softwood [ 36 ], grey alder wood [ 37 ], banana bunch [ 38 ], bamboo chips [ 35 , 39 ], hemp shives and wheat straw [ 19 , 40 ], rice straw [ 41 ], and Arundo donax L. [ 42 , 43 , 44 , 45 ].…”