Turgay Akbulut

Wettability and surface roughness characteristics of medium density fiberboard panels from rhododendron (Rhododendron ponticum) biomass

Wettability and surface roughness properties of medium densityberboard (MDF) panels made from Rhododendron biomass were examined in this study. Rhododendron dominates the understory layer of the forests throughout the Black Sea Region in Turkey with substantial biomass potential. � is study was conducted to evaluate suitability of Rhododendronber for MDF production. For the experiments, rhododendron and commercially-manufactured-chip (Pinus sylvestris L. and Quercus robur L.) with 11% moisture content were used. � e mixing ratios of rhododendron with commercially-manufactured-chip were 100:0, 75:25, 50:50, 25:75 and 0:100 %, respectively. Commercial urea formaldehyde (UF) adhesive was used as a binder. A stylus method was employed to evaluate the surface characteristics of the samples. Roughness measurements by the stylus method were taken perpendicularly to theber. � ere was a signicant dierence (p=0.05) between surface roughness parameters (R a , R z , R q , and R y ). � e results obtained in this study revealed that all the panels have met the general purpose-use requirements of European Norm (EN). It was found that panels made with a 25/75 ratio of rhododendron to commercially-manufactured-chip had a signicantly lower contact angle (88.14 o ) than panels made with a 100/0 ratio (117.91 o ). Surface roughness measurements are based on four roughness parameters, average roughness (R a ), mean peak-to-valley height (R z ), root mean square roughness (R q ), and maximum peak-to-valley height (R y ) were considered to evaluate the surface characteristics of the panels and supported the above � ndings as the panels made with a 25/75 ratio had a slightly rougher surface with average values of 2.929 �m (R a ). From the tests performed, we conclude that increasing the rhododendron mixing portion increased surface roughness and decreased wettability. Based on these results, rhododendron biomass could be an alternative raw material for MDF manufacturing.

Physical and mechanical properties of nanoreinforced particleboard composites

Novel composite materials having desired performance properties can be developed by nanotechnology. The major objective of this research was to produce nanomaterial-reinforced particleboard composites with enhanced physical and mechanical performance. Urea formaldehyde adhesive used to produce particleboard composites was reinforced with nanoSiO2, nanoAl2O3, and nanoZnO at loading level of 0%, 1%, and 3%. To evaluate physical properties density, thickness swelling, water absorption, and equilibrium moisture content were determined while modulus of rupture, modulus of elasticity, bonding strength, and screw withdrawal strength tests were carried out to evaluate mechanical properties of the particleboard composites. The results acquired in this work revealed that nanomaterial reinforcement technique significantly affected the physical and mechanical performance properties of the particleboard composites. The findings showed that the modulus of rupture, modulus of elasticity, bonding strength, and screw withdrawal resistance of the composites improved by all the nanomaterials used in this study, except 3% nanoZnO. It was also determined that using 1% nanoSiO2 or 1% nanoAl2O3 in the composites had the best results in the bonding strength and screw withdrawal resistance. The findings indicate that it is possible to produce novel wood composites by using proper nanomaterial type and loading level.

ÇEŞİTLİ ÜRETİM DEĞİŞKENLERİNİN YONGALEVHANIN TEKNOLOJİK ÖZELLİKLERİ ÜZERİNE ETKİSİ (THE EFFECT OF VARIOUS MANUFACTURING VARIABLES ON TECHNOLOGİCAL PROPERTIES OF PARTICLEBOARDS)

CEŞITLI URETIM DEĞIŞKENLERININ YONGALEVHANIN TEKNOLOJIK OZELLIKLERI UZERINE ETKISI (THE EFFECT OF VARIOUS MANUFACTURING VARIABLES ON TECHNOLOGICAL PROPERTIES OF PARTICLEBOARDS)