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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 nanoSiO 2 , nanoAl 2 O 3 , 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% nanoSiO 2 or 1% nanoAl 2 O 3 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.

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Compression wood (CW) is a reaction wood formed in gymnosperms in response to various growth stresses. Many of the anatomical, chemical, physical, and mechanical properties of CW differ distinctly from those of normal wood. Because of different properties, the CW is much less desirable than normal wood. This study was conducted to investigate the suitability of CW flour obtained from black pine (Pinus nigra Arnold) in the manufacture of wood plastic composite (WPC). Polypropylene (PP) and CW flour were compounded into pellets by twin-screw extrusion, and the test specimens were prepared by injection molding. WPCs were manufactured using various weight percentages of CW flour/PP and maleic anhydridegrafted PP (MAPP). Water absorption (WA), modulus of rupture (MOR), and modulus of elasticity (MOE) values were measured. The results showed that increasing of the CW percentage in the WPC increased WA, MOR, and MOE values. Using MAPP in the mixture improved water resistance and flexural properties. CW flour of black pine can be used for the manufacturing of WPC as a reinforcing filler.

Water absorption and mechanical performance of the injection‐molded hybrid composites prepared from different ratios of two polymer blends (57 wt%), two compatibilizers (3 wt%), and two wood species (40 wt%) were investigated. The ratio of polypropylene and high‐impact polystyrene (HIPS) gradually increased in the blend (from 10 to 30 wt%). Styrene–ethylene–butylene–styreneblock copolymer and maleic anhydride‐grafted PP (MAPP) were used as compatibilizer (3 wt%). The shore D hardness of the PP/wood composites was improved by the incorporation of the HIPS. The HIPS/wood flour composites showed higher tensile modulus but lower tensile strength than the PP/wood composites. The water resistance of the PP/wood composites decreased with increasing HIPS content. POLYM. COMPOS., 38:863–869, 2017. © 2015 Society of Plastics Engineers

Wettability and surface roughness properties of medium density berboard (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 Rhododendron ber 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 the ber. ere was a signi cant di erence (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 signi cantly 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 μm (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.

. 2007. Effects of some sanding factors on the surface roughness of particleboard. Silva Fennica 41(2): 373-378.Effects of the grit sizes of the sand belt, feeding speed and the feed power of the heads of the sander on the surface roughness of the particleboard panels were investigated. Two surface roughness parameters, average roughness (R a ) and mean peak-to-valley height (R z ), obtained from board surfaces were used in the analysis. Sanding factors were found to have a significant effect on the surface roughness of the particleboard. Better results were obtained with 40 m/min of feeding speed, 40-60-80-120 of grit sizes, and 67 kW of the feed power of the heads of the sander.