PROPERTIES OF FLAT-PRESSED WOOD-POLYMER COMPOSITES MADE USING SECONDARY POLYETHYLENE

The influence of wood filler type (particles, flour, mixture of waste chips and sawdust at ratio 10:90), its content (20, 40, and 60 %), board density (800, 900, and 1000 kg.m(-3)), pressing temperature (160, 180, and 200 degrees C) and pressing time (6.4, 8.0, and 9.6 min) on the properties of flat-pressed wood-polymer composites (WPC) using a conventional flat-press process was investigated in this study. Dry-blending method was applied for mixing wood fillers and secondary polyethylene (sPE). The highest strength and water resistance were observed in flat-pressed WPC made using wood particles. The highest values of bending strength were noticed in WPC with 40 % content of wood particles and 60 % content of sPE. The further increase or decrease of wood particles content results in reduction of the bending strength values. Water resistance of flat-pressed WPC improves with the increasing of secondary polyethylene contents from 40 % to 80 %. With increasing board density from 800 to 1000 kg.m(3) the properties of flat-pressed WPC also improved. With increasing pressing temperature from 160 to 200 degrees C and pressing time from 6.4 to 9.6 min the strength of flat-pressed WPC noticeably increased and water resistance considerably improved.