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It is known that there is a correlation between hydration heat and physico-mechanical properties of wood based cement panels. Cement hydration is affected by many variables, such as chemical composition, water/ cement ratio, wood/cement ratio, wood chemical properties, mineral additions and producing conditions. This study mainly aimed to investigate the effects of press temperature on some properties of three-layer cement bonded particleboard made from the particles of spruce (Picea orientalis) and poplar (Populus tremula). For this purpose, a total of 16 experimental board groups with 1200 kg/m 3 target density and 1/3 wood-cement ratio were produced at the press temperatures of (20, 30, 40, 50, 60, 70 and 80) °C. As cement curing accelerator, CaCl 2 was used at a rate of 5 % (cement weight basis). The physical, mechanical and thermal properties of the boards were determined. The results indicated that the press temperature substantially affected the properties of cement-bonded particleboard depending on the wood species. In the light of this study, the optimum temperatures in producing of cement-bonded particleboard were found as 40 °C for poplar wood and 60 °C for spruce wood.

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In this study, the effects of hardener type (ammonium chloride and ammonium nitrate) and board thickness on the physical (density, thickness swelling and water absorption), mechanical (modulus of rupture, modulus of elasticity, internal bond strength, screw withdrawal resistance and surface durability) and formaldehyde content of particleboard were investigated. Three types panels were produced using 11-9% urea-formaldehyde adhesive (core and surface, respectively), with 650 kg/m 3 target density, 150°C pressing temperature, 20-24 kg/cm 2 pressure, and 6 min of pressing time. The analyses revealed that use of ammonium nitrate for particleboard manufacturing resulted in improved water absorption and thickness swelling properties after 24 h of immersion in water. In addition, the using ammonium nitrate has no significant effect by Modulus of rupture (MOR) and modulus of elasticity (MOE). However, internal bond strength, screw withdrawal resistance and surface durability properties were positively affected by using ammonium nitrate. Formaldehyde content value was decreased by about 5%. The study demonstrated that the boards made of ammonium nitrate meet the requirements for general standard and building materials.