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The usability of lavender stems along with red pine chips was investigated as raw materials in the production of particleboard. Medium-density particleboard was manufactured using urea formaldehyde glue at three different ratios for five different mixture groups containing lavender stems and red pine chips. Some physical and mechanical properties of the boards were investigated. According to the statistical studies of the results, decreasing the ratio of lavender stems between board groups reduced the thickness swelling value. The internal bond strength, bending strength, and elastic modulus values of all board groups (%10-12 glued) were above the minimum values set by the TS-EN-312 standard for general purpose particleboard. According to these results, either lavender stems alone or together with red pine chips are suitable for use as a new raw material for particleboard manufacturing.

Sunflower stalks (Helianthus annuus) were studied as an alternative raw material for cement bonded particleboard. Experimental cement bonded particleboards measuring 500 mm × 500 mm × 12 mm with nominal density of 1300 kg/m3 were produced using different ratios of sunflower stalk particles with wood. Properties of the cement bonded particleboards evaluated include water absorption, thickness swelling, screw withdrawal strength and bending properties. Results of the study showed that the addition of small amount of sunflower stalks in the production of cement bonded particleboard does not significantly influence the properties tested. Inclusion of more stalks in the mixture significantly decreases mechanical properties and raises thickness swelling and water absorption values of the cement bonded particleboard. Results indicate that boards which include a small amount of sunflower stalks provide properties required by the standards for general purpose-use cement bonded particleboards.

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The effects of some polymer additives, also called super plasticizers, on selected physical and mechanical properties of cement bonded particle board were investigated. Two different kinds of poly carboxylic ether (PF300, DX40) and a melamine based polymer (300M) were added to the wood cement mixture. The ratios of polymer additives to the wood cement mixture were 1%, 1.2% and 1.4%. Cement bonded particleboards were manufactured with wood/cement (w/w) ratio of 1:3; target density of 1300 kg.m-3, and CaCl2 content of 5%. The cement bonded particleboards were tested for water absorption (2 and 24 hour), thickness swelling (2 and 24 hour), bending stiffness and strength and internal bond strength. Results of the study showed that most of the polymer addition decreased water absorption and thickness swelling of the boards. Replacement of cement with polymers increased internal bond strength and bending stiffness of the boards while bending strength was slightly reduced. Use of small amount of super plasticizers significantly improves most of the board properties.