Drvna Industrija (Sep 2016)
Physical Properties of Boards Manufactured with Hygrothermally Treated Tepa (Laureliopsis Philippiana Looser) Particles
Abstract
Three layer particleboards were manufactured using hygrothermally treated and untreated Laureliopsis philippiana (tepa) particles with urea-formaldehyde (UF) resin. Hygrothermal treatment consisted of autoclaving particles at 150 °C for 90 min (430 kPa) in a steam saturated atmosphere. Density, moisture content, swelling and water absorption were determined. Equilibrium moisture, dimensional variation in length and thickness, as well as length and thickness coefficients per every 1 % change in board equilibrium moisture were also determined after acclimatization at different relative air humidity conditions (20 °C; 40, 50, 60, 70, 80 and 90 % RAH). There were significant differences between particleboards made from control and treated particles. Boards manufactured with treated particles showed a reduction in moisture content, swelling and water absorption. Dimensional stability analysis in response to relative air humidity (RAH) showed that the hygrothermal treatment causes a reduction in equilibrium moisture, a decrease in length and thickness dimensional variation, likewise a reduction in length and thickness swelling coefficients.
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