| Popis: |
Effects of continuous press speed (580 and 600 mm/s) and conditioning time (0 and 72 h) on some physical and mechanical properties and formaldehyde content of particleboards were investigated. The 18 mm thick boards were manufactured using urea-formaldehyde, with a 50% pine, 40% oak wood, and 10% poplar biomass mixture of the wood materials. According to the results of the unconditioned samples, the density, modulus of rupture (MOR), moisture content (MC), thickness swelling (TS), and water absorption (WA) were increased 0.8%, 4.4%, 0.4%, 4.4%, and 5.5% when press speed increased from 580 to 600 mm/s, while thickness, modulus of elasticity (MOE), internal bond (IB), surface soundness (SS), and free formaldehyde (FF) were decreased 0.3%, 4.9%, 2.4%, 10.6%, and 21.1%, respectively. On the contrary to the results of unconditioned samples, MOE and SS were increased 1% and 1.4%, respectively, and WA was decreased 3.5% with the increase in press speed when samples were conditioned for 72 h. Free formaldehyde content was the most prominent parameter influenced by the increase in press speed both for the unconditioned and 72 h conditioned samples. |
