EFFECTS OF THERMAL TREATMENT OF RUBBERWOOD FIBRES ON PHYSICAL AND MECHANICAL PROPERTIES OF MEDIUM DENSITY FIBREBOARD
Keywords:Thickness swelling, flexural properties, internal bond strength, screw withdrawal resistance, hydrophobicity
AYRILMIS N, JARUSOMBUTI S, FUEANGVIVAT V & BAUCHONGKOL P. 2011. Effects of thermal
treatment of rubberwood fibres on physical and mechanical properties of medium density fibreboard. This
study evaluated effects of thermal treatment of rubberwood fibres at elevated temperatures on physical and
mechanical properties of medium density fibreboard (MDF). MDF panels were manufactured from untreated
rubberwood fibres and fibres treated at three different temperatures (120, 150 or 180 °C) for 15 or 30 min in
a laboratory autoclave. The thickness swelling of the panels decreased with increasing treatment temperature
and time while mechanical properties, flexural properties, internal bond strength and screw withdrawal
resistance, decreased. Results of the internal bond strength showed that thermal treatment of rubberwood
fibres increased the hydrophobicity of fibre surfaces, which reduced the adhesion and penetration of the ureaformaldehyde
resin. In general, all panel types met the general purpose use requirements of EN standards.
MDF panels made from thermally-treated rubberwood fibres at 180°C for 30 min appeared to be a practical
choice for applications requiring low thickness swelling.