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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.

Determining the mechanical properties of particleboard has gained a great importance due to its increasing usage as a building material in recent years. This study aims to develop artificial neural network (ANN) and multiple linear regression (MLR) models for predicting modulus of rupture (MOR) and modulus of elasticity (MOE) of particleboard depending on different pressing temperature, pressing time, pressing pressure and resin type. Experimental results indicated that the increased pressing temperature, time and pressure in manufacturing process generally improved the mechanical properties of particleboard. It was also seen that ANN and MLR models were highly successful in predicting the MOR and MOE of particleboard under given conditions. On the other hand, a comparison between ANN and MLR revealed that the ANN was superior compared to the MLR in predicting the MOR and MOE. Finally, the findings of this study are expected to provide beneficial insights for practitioners to better understand usability of such composite materials for engineering applications and to better assess the effects of pressing conditions on the MOR and MOE of particleboard.

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In this study, it is aimed to determine the effect of the use of different types cement and accelerator on the physicomechanical properties of cement-bonded particleboards. Within this scope, two types of cements (calcium aluminate cement and Super white CEM I 52.5 R) and accelerators (aluminum sulfate and calcium chloride) were used in the production of boards. Therefore, CBPBs with 1200 kg/m 3 target density and 1/2.75 wood-cement ratio were produced. Based on cement weight 1.5% accelerators were used. The test results obtained were evaluated according to EN 634-2 (2009). According to result, density values of the boards were changed with using depending on cement and accelerator types. The use of super white cement and calcium chloride positively affected the both mechanical properties and dimensional stability of the boards. The use of calcium aluminate cement and aluminum sulfate resulted in lower strength properties.