The influence of hot pressing on high density fibreboards, when the panels are used for overlaying
Keywords:melamine/urea-formaldehyde resin, high density fiberboards, thermal modification, hot-pressing, mechanical properties
AbstractA series of high density fiberboard (HDF) panels, bonded with melamine/urea-formaldehyde (MUF), were exposed to a post manufacture hot pressing at various temperatures and pressing durations using a hot press and just enough pressure to ensure firm contact between the panel and the press platens. The experimental plan was developed for three different temperatures of 95, 180 and 210ºC and two different pressing times, of 22 and 35 seconds. The panels were made with pine fibers (pinus pinaster) at a target density of 930 kg/m3 and target thickness of 6.7 mm. The results indicated that the pos-manufacture hot-pressing of the exterior HDF panels resulted in a slightly improvement of the modulus of elasticity (MOE), bending strength and internal bonding (IB) of the panels used as substrates. A reduction in moisture content and thickness as well as an increase in density and thickness swelling was also noticed with an increase in the temperature and pressing time.
• Ayrilmis, N. (2012). Enhancement of dimensional stability and mechanical properties of light MDF by adding melamine resin impregnated paper waste. Int. J. of Adhesion and Adhesives, 33: 45-49.
• Ayrilmis, N., Buyuksari, U. & As, N. (2010). Bending strength and modulus of elasticity of wood-based panels at cold and moderate temperatures. Cold Regions Science and Technology, 63: 40–43
• Ayrilmis, N., Laufenberg T. L. & Winandy, J. E. (2009). Dimensional stability and creep behaviour of heat-treated exterior medium density fibreboard. Eur. J. Wood Prod., 67: 287-295.
• Ayrilmis, N. (2007). Effect of panel density on dimensional stability of medium and high density fibreboards. J Mater Sci., 42: 8551-8557.
• Bardak, S., Sari, B., Nemli, G., Kirci, H. & Baharoglu, M. (2011). The effect of decor paper properties and adhesive type on some properties of particleboard. Int. J. of Adhesion & Adhesives, 31: 412-415.
• Büyüksari, Ü. (2013). Surface characteristics and hardness of MDF panels laminated with thermally compressed veneer. Composites: Part B Engineering, 44(1): 675-678.
• Büyüksarı Ü., Hiziroglu, S., Akkılıç H. & Ayrılmıs, N. (2012). Mechanical and physical properties of medium density fiberboard panels laminated with thermally compressed veneer. Composites: Part B Engineering 43: 110-114. March 2012. DOI: 10.1016/j.matdes.
• Chow, P, Janowiak J. J. & Price E. W. (1996). The internal bond and shear strength of hardwood veneered particleboard composites. Wood and Fiber Science, 18(1): 99-106.
• Chow, P. (1976). Properties of medium-density, dry-formed fiberboard from seven hardwood residues and bark. Forest Products Journal, v. 26, n. 5, pp. 48-55.
• Esteves, B. M., Domingos, I. J. & Pereira, H. M. (2007). Pine wood modification by heat treatment in air. Bioresources, 3(1): 142-154.
• Frihart, C. R, (2005). Wood adhesion and adhesives. In: R. M. Rowell (Ed.). Handbook and wood chemistry and composites. CRC Press, London, pp. 215-278.
• Grigsby, W., Thumm, A. & Carpenter, J. (2012). Fundamentals of MDF panel dimensional stability: Analysis of MDF high-density layers. J. of Wood Chemistry and Technology, 32: 149-164.
• Maloney, T. M. (1989). Modern particleboard & dry-process fiberboard manufacturing. San Francisco: Miller Freeman Publication.
• Maloney, T. (1977). Modern particleboard and dry process fibreboard manufacturing. Miller Freeman Publications, CA, USA. ISBN: 0879300639.
• Mohebby, B., Ilbeighi, F. & Kazemi-Najafi, S. (2008). Influence of hydrothermal modification of fibers on some physical and mechanical properties of medium density fibreboard (MDF). Holz Roh Werkst 66: 213-218.
• NP EN 317 (2002). Aglomerado de partículas de madeira e aglomerado de fibras de madeira. Determinação do inchamento em espessura após imersão em água.
• NP EN 310 (2002). Placas de derivados de madeira. Determinação do módulo de elasticidade em flexão e da resistência à flexão.
• NP EN 319 (2002). Aglomerado de partículas de madeira e aglomerado de fibras de madeira. Determinação da resistência à tração perpendicular às faces da placa.
• NP EN 322 (2002). Placas de derivados de madeira. Determinação do teor de água.
• NP EN 323 (2002). Placas de derivados de madeira. Determinação da massa volúmica.
• Nelson, N. D. (1973) Effects of wood and pulp properties on medium-density, dry-formed hardboard. Forest Products Journal, v. 23, n. 9, pp. 72-80, Sep. 1973.
• Pizzi A. (1994). Advanced wood adhesives technology. Marcel Dekker Inc, New Work.
• Stamm, A. J. (1956). Thermal degradation of wood and cellulose. Ind End Chem 48(3): 413-417.
• Tjeerdsma, B. F. & Militz, H. (2005). Chemical changes in hydrothermal treated wood: FTIR analysis of combined hydrothermal and dry heat-treated wood. Holz Roh- Werkst, 63: 102-111.
• Vansteenkiste, R. (1981). Surface treatment of wood based panels. Seminar on wood based panels and furniture industries. Beijing, China.
• Wong, Ee D., Zhang M., Han Q. W. G. & Kawai S. (2000). Formation of the density profile and its effects on the properties of fibreboard. J wood science, 46(3): 202-209.
• Wu, Q. (1999). In-plane dimensional stability of oriented strand panel: effect of processing variables. Wood and fiber science, 31(1): 28-40.
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