Cenk Demirkir

Characteristics of plywood panels produced with urea formaldehyde resin (UF) containing borax

The effects of boron treatments on mechanical, biological, and dimensional properties of wood and wood based materials have been widely investigated. The measurement conducted with desicator method (Colak and Colakoglu 2004) showed that formaldehyde emission of plywood panels impregnated with borax decreased. Shear strength, formaldehyde emission, and bending characteristic of plywood panels produced with an adhesive mixture containing borax were examined in this study.

Utilization Potential of Waste from Window Joints for Particleboard

The aim of this study was to determine some technological properties of particleboard made from the waste from window joints. The effect of board density, adhesive amount, and paint presence on the properties of particleboard was investigated. Increasing density and adhesive amount significantly improved their mechanical properties and surface roughness, but negatively affected their thickness swelling. Removing of the paint from the particle resulted in better mechanical properties, but poorer (higher) surface roughness values. This treatment did not statistically affect the thickness swelling. Based on the results, it is proved that the waste of window joints has a potential as raw material for the manufacture of particleboard.

The effect of grain direction on lateral nail strength and thermal conductivity of structural plywood panels

The aim of study was to determine the effects of grain direction on the lateral nail strength and thermal conductivity of structural plywood panels. Experiment were made with plywood manufactured from Scots pine, maritime pine and black pine. A rotary peeler with a maximum horizontal holding capacity of 80 cm was used for veneer manufacturing. The highest values of max load (2,17 kN), stiffness (2,52 kN/ mm) and displacement at ultimate load (36,8 mm) were obtained from C1PR group panels manufactured from black pine. Also, it was determined the mechanical properties in perpendicular to grain were higher than those in parallel to grain. The black pine panels gave highest average thermal conductivity value (0,168 W/mK), while that of Scots pine was lowest (0,145 W/mK). Thermal conductivity of panels in perpendicular to the grain of main axis of plywood was always found to be higher than the values obtained from measurements parallel to the grain.

Formaldehyde emission from particleboards manufactured with waste materials from plywood industry

ZusammenfassungPeeling cores, dried veneer residues and plywood edge pieces containing adhesive are used for particleboard production. So, in this study, the effect of waste materials from plywood industry used for particleboard manufacturing on the formaldehyde emission of panels was investigated.

Thermal insulation properties of hybrid textile reinforced biocomposites from food packaging waste

Due to the significant and harmful effect of the global warming on our communities, health, and climate, the usage of thermal insulation material in building is must to decrease the energy consumption and to improve energy efficiency. On the other hand, the utilization of waste and biomass resources for developing new bio-based composite materials is attracting much attention for the environmental and socioeconomics. Therefore, in this study, thermal insulation bio-based composite panels from Tetra Pak® waste and wool fiber waste with different ratios were manufactured. Likewise, other sandwich bio-based composite panels were manufactured using Tetra Pak waste as a core material with glass woven fabric and jute wove fabric as skin materials. Thermal conductivity and thermal resistance results showed a significant improvement on thermal insulation properties of the developed biocomposite panels compared to the control samples made of plain Tetra Pak®.

Effects of plasma surface treatment on bending strength and modulus of elasticity of beech and poplar plywood

This is a study on the effect of plasma treatment with different gases and plasma intensity on the bending strength and modulus of elasticity of plywood manufactured from beech and poplar. Oxygen (O2) and ammonia (NH3) plasma were applied on the veneer sheets; two plasma intensities were applied on the veneers with 150 and 300 W in the plasma chamber during one minute. Phenol formaldehyde resin was applied on one surfaces of each veneer with approx. 160 g/m2. Bending strength and modulus of elasticity were determined according to EN 310.The effects of plasma surface treatment on chemical structure of the panels were determined with FTIR-ATR analysis. Bending strength of all tested panels slightly and partly increased without statistical significance when applying oxygen plasma. The effect of ammonia plasma treatment on bending strength and was determined by the wood species and the plasma intensity, and it was not uniform. Modulus of elasticity of the panels with oxygen plasma treatment showed in most cases improvement, whereas ammonia plasma pretreated veneers caused lower values compared to the control panels.

Effect of Manufacturing Factors on Technological Properties of Plywood from Northern Turkey and Suitability of Panels for Use in Shear Walls

AbstractShear walls provide the lateral resistance needed for light-frame wood structures to withstand earthquake and wind loads. When sheathed with wooden structural panels, shear walls can be strong, stiff, and ductile. This is a study on the effect of wood species and drying temperature of veneer on the suitability of plywood for use in shear walls resisting earthquake loads. The highest lateral nail strength values were obtained from plywood panels manufactured from black pine veneers dried at 160°C. Group C (black pine) showed the highest maximum load values and the greatest displacement at ultimate load, whereas Group A (Scots pine) showed the lowest maximum load values and the least displacement at ultimate load. The stiffness values (2.38, 2.52, and 2.28 for Groups C1, C2, and C3, respectively) in Group C were higher than those of the other groups. The results exceeded the values for standards described in National Design Specification for Wood Construction and ISO 16670 and also met the values in...