The effects of succinic anhyride modification on properties of medium density fiberboard (MDF)

Use Effects of Succinic Anhydride Modification on Properties ©f Medium Density Fiberboard (MDF) In this study fibers obtained from poplar wood {Populus euramericcma 1-214) were modified in different reaction time and temperatures by succinic anhydride and maleic anhydride. It was aimed to improve properties of Medium Density Fiberboard (MDF). It were determined weight percent gain, acid value, saponification value, monoester, diester and total ester content, water repellent value, pH and color differences of modified fibers. MDF was produced using fibers modified with succinic anhydride and different adhesives types (urea formaldehyde, phenol formaldehyde, melamin urea formaldehyde, melamin formaldehyde) and ratios. It were investigated modulus of rupture, tensile strength, water absorption, thickness swelling, sorption isotherms, biological resistance, surface roughness, hardness, and color difference properties on MDF. When the weight percent gain, monoester, diester content of modified fibers were taken into account the optimal conditions were defined as following: anhydride ratio 50% (based on weight of oven-dried fiber), reaction temperature 120 °C and reaction time 90 min for succinic anhydride; anhydride ratio 50% (based on weight of oven-dried fiber), reaction temperature 100 °C and reaction time 90 min for maleic anhydride. Since fibers modified by maleic anhydride have acidic properties, it was a problem to produce MDF. For this reason, fibers modified with succinic anhydride were used for MDF. While modulus of rupture, tensile strength, biological resistance of MDF produced from fibers modified with succinic anhydride depends on the adhesive type and ratio were improved, it was established that 2 and 24 h water absorption, thickness swelling and sorption isotherms of these MDF decreased. In addition, it was determined that surface roughness of MDF produced from succinylated fibers was better than control boards. Hardness of MDF produced from succinylated fibers was lower than control boards. It was also detected that the color of MDF produced from fibers modified with succinic anhydride was dark. Key Words: Succinic Anhydride, Maleic Anhydride, Medium Density Fiberboard, Populus Euramericana