A Sustainable Strategy for Medium-Density Fiberboards Preparation from Waste Hybrid Pennisetum Straws

Abstract

The remaining waste residues of crops such as straws are considered a sustainable material that can be used in the manufacture of medium-density fiberboards (MDF). The hybrid Pennisetum straw has a high cellulose content, which gives it the potential to be used as a sustainable material in the manufacturing of MDF. In this study, a hot-pressing method was used to obtain MDF with a density of 650 kg m−3 and a thickness of 15 mm from hybrid Pennisetum straws. The effect of pressing temperatures on the thermal stability and physical properties of the obtained MDF was discussed. The results showed that the MDF obtained by hot pressing at 195 °C for 7.5 min had the optimum physical properties, which contained a static bending strength of 12.33 MPa, a nail holding force of 1313 N, and an elastic modulus of 2572 MPa. The mechanism of interfacial adhesion between fiber and resin was investigated. It was found that increasing the pressing temperature not only promoted the curing of the urea–formaldehyde resin, but also promoted the degradation of hemicellulose and lignin inside the straws.