Effect of Initial Moisture Content of Chips and Steaming Time on the Properties of Medium Density Fiberboard

Abstract

The objective of this study was to investigate the effect of initial moisture content and steaming time of chips on medium density fiberboard (MDF) properties. Acacia mangium (Acacia mangium Willd.) chips with specific moisture content levels (10, 30, 60 and 90%) controlled in advance were steamed for 3 to 18 minutes under a steam pressure of 0.70 MPa before refining of fibers. In the case of chips with higher moisture content, the content of short fibers decreased and the modulus of rupture (MOR) of MDF increased by steaming. MOR and internal bond (IB) decreased with increased steaming time. It is presumed that the decrease was due to degradation of hemicellulose. It is concluded that high MOR values can be obtained by using chips with high moisture content and short steaming time when Acacia mangium is used as the raw material for MDF.