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In this study, under laboratory conditions, hazelnut husk and astragalus plant were mixed separately into black pine wood chips, and multi-purpose boards were produced from the obtained chips with urea formaldehyde glue. After the hazelnut husk and astragalus plant were dried and ground, they were added to the chip and glue mixture in certain proportions. Hazelnut husk mixture ratios were applied as 100 %; 0 %, 75 %; 25 %, 50 %; 50 %, 25 %; 75 %, 0 %; 100 % to black pine wood chip in the particle board mixture. These ratios were made in the same way for the astragalus plant. From these mixtures, chipboard blanks of 16 mm thickness and densities between 0,68 g/cm3 and 0,72 g/cm3 were produced. Density, moisture content, thickness increase, water intake, bending strength, modulus of elasticity in bending and tensile strength perpendicular to the surface were tested in physical and mechanical experiments. According to the results obtained, as the participation rate of hazelnut shells and astragalus increased, the durability properties of the panels decreased. At the same time, it shows that the technological properties of the panels produced by adding up to 25 % astragalus plant and hazelnut shells to the mixture comply with the standards.

In the production of particleboard, the chips emerging from the drying oven usually pass into the bonding process without sufficiently cooling down. Moreover, along with the effect of friction during the bonding process, the increased chip temperature boosts the consumption of resin/adhesive and affects the properties of the board. This study investigated the effect of chip temperature during the bonding process on the properties of particleboard. With this aim, the effects were determined for six different temperatures (25 °C, 30 °C, 35 °C, 40 °C, 50 °C, 55 °C) measured during the bonding of the chips. According to the results, optimum board properties were obtained from the groups in which the chip temperature measured during the bonding process was 30 °C - 40 °C. Furthermore, it was determined that chip temperatures of above 40 °C during the bonding process significantly reduced the mechanical properties. [ABSTRACT FROM AUTHOR]

Particleboard can be produced from a mixture of different lignocellulosic materials, which can be chosen depending on the density required for the panel and its applications. The aim of this study was to evaluate the mechanical properties of particleboard with bamboo, pine and mate for a new product of high density for the special applications currently served by HDF. Particles of bamboo (Phyllostachys aurea) finely chopped sticks of mate (Ilex paraguariensis) and commercial particles of southern pine (Pinus taeda) wood were used. These particles used 100 % by weight in the panel or in mixtures of 50 % each (three mixtures) or in a triple mixture of one third each, were glued in a drum-type rotary mixer with melamine-urea-formaldehyde (MUF) resin, and pressed in hydraulic press at 120 °C and 5,88 MPa for 10 minutes, up to 6 mm thickness. The panels were produced with 900 kg/m3 nominal density and, after pressing, were conditioned at 20 °C and 65 % relative humidity. Statistical was performed by means the variance analysis and simplex centroid experimental design, with three replicates. It was found the use of pine particles contributed mainly to increase the panel's strength and stiffness, while the use of mate particles facilitated internal bond strength. The mixtures modeling showed that the water absorption, the strength and stiffness in bending and the internal bond strength are explained by the cubic model, while the thickness swelling and hardness are explained by the quadratic model. The best physical and mechanical properties results were found for the pine, bamboo and mate same ratio mixture. [ABSTRACT FROM AUTHOR]

In this study, Its the influence of according to press, particleboards produced in two different press types which were multiday and continuous hot press, the thickness, density, bending strength, modulus of elasticity, internal bond, surface soundness, withdrawal of screw resistance, moisture, thickness swelling, water absorption, formaldehyde emission content were researched. 18 mm x 2100 mm x 2800 mm size particleboards were manufactured on the production line which was using urea-formaldehyde (F:U;1,07 moles), and 30 % pine, 40 % oak, 20 % beech and 10 % poplar waste mixture of the wood materials. According to results of the tests performed after the multiday and continuous hot press production of the boards; thickness (0,63 %), bending strength (1,27 %), moisture content (0,47 %), thickness swelling (37 %), and water absorption (39,9 %), modulus of elasticity (11,35 %), internal bond (7,22 %) were increased according to multiday hot press while density (2,7 %), surface soundness (18,81 %), withdrawal of screw resistance (14 %) and formaldehyde (57,12 %) decreased. Formaldehyde content, surface soundness, withdrawal of screw resistance are the most prominent properties influenced by continuous hot press. [ABSTRACT FROM AUTHOR]

The present work regards an attempt to obtain particles from the post-industrial pine plywood in a single- shaft shredder. A screen mesh size determines the wood particles characteristics. In the work 10-, 14-, 25- and 38-mm mesh size screens were used. The urea-formaldehyde (UF) and phenol-formaldehyde (PF) bonded plywood were shredded separately, so that the effect of the binder type could be analyzed. The determined fractional composition, bulk density, dimensions and surface area of the particles were compared to the industrial virgin pine particles dedicated to the core layer of particleboards. The results showed that the particles obtained from a 14-mm mesh screen exhibited properties closest to those found for the virgin particles. [ABSTRACT FROM AUTHOR]

The purpose of this study was to develop an automatic indirect (non-invasive) system to identify the condition of drill bits on the basis of the measurement of feed force, cutting torque, jig vibrations, acoustic emission and noise which were all generated during machining. The k-nearest neighbors algorithm classifier (k-NN) was used. All data analyses were carried out in MATLAB (MathWorks - USA) environment. It was assumed that the most simple (but sufficiently effective in practice) tool condition identification system should be able to recognize (in an automatic way) three different states of the tool, which were conventionally defined as "Green" (tool can still be used), "Red" (tool change is necessary) and "Yellow" (intermediate, warning state). The overall accuracy of classification was 76% what can be considered a satisfactory result at this stage of studies. [ABSTRACT FROM AUTHOR]

It is known that there is a correlation between hydration heat and physico-mechanical properties of wood based cement panels. Cement hydration is affected by many variables, such as chemical composition, water/cement ratio, wood/cement ratio, wood chemical properties, mineral additions and producing conditions. This study mainly aimed to investigate the effects of press temperature on some properties of three-layer cement bonded particleboard made from the particles of spruce (Picea orientalis) and poplar (Populus tremula). For this purpose, a total of 16 experimental board groups with 1200 kg/m³ target density and 1/3 wood-cement ratio were produced at the press temperatures of (20, 30, 40, 50, 60, 70 and 80) °C. As cement curing accelerator, CaCl2 was used at a rate of 5 % (cement weight basis). The physical, mechanical and thermal properties of the boards were determined. The results indicated that the press temperature substantially affected the properties of cement-bonded particleboard depending on the wood species. In the light of this study, the optimum temperatures in producing of cement-bonded particleboard were found as 40 °C for poplar wood and 60 °C for spruce wood. [ABSTRACT FROM AUTHOR]

In this paper, the impacts of heartwood and sapwood usage on the physical, mechanical, and surface properties and formaldehyde emission of particleboard are investigated. European Larch (Larix decidua) trees are chosen as a raw material. The logs are divided into three segments: sapwood, heartwood and total wood. The highest amounts of cellulose (51,54%), and hemicelluloses (22,24%) in the sapwood, followed by total wood, and the heartwood, respectively. However, the highest amount of lignin (30,54%) was found in the heartwood. The highest extractives values are obtained from heartwood, followed by total wood, and the sapwood, respectively. While the lowest pH value (3,03) is found in heartwood, the sapwood samples provide the highest values (4,95). The highest ash (0,49%) content and amount of condensed tannin (13,89%) are extracted from heartwood, followed by total wood, and sapwood, respectively. The test panels manufactured from sapwood have the smoothest surface (7,49 μm (Ra), 48,86 μm (Ry), and 35,12 μm (Rz)) and the lowest contact angles (67,8°), while the roughest surface (14,20 μm (Ra), 68,05 μm (Ry), and 50,02 μm (Rz)) and highest contact angle (96,9°) are obtained from the panels of heartwood. The thickness swelling (19,88%) and formaldehyde emission (7,28%) values of the panels manufactured from heartwood are significantly lower than the panels manufactured from the total wood and sapwood. The highest modulus of rupture (MOR), modulus of elasticity (MOE), and internal bond (IB) values are observed on sapwood, respectively, 15,60 MPa (MOR), 2201 MPa (MOE), and 0,523 MPa (IB). These mechanical strength values (MOR, MOE, and IB) are followed by total wood, and the heartwood, respectively. Surface smoothness and wettability of the particleboards manufactured from sapwood are better than those of total wood and heartwood. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the feasibility of construction and demolition (C&D) waste wood to produce of particleboard. The raw material was obtained from a waste recycling company and it was divided into four types of materials: MDF (medium density fiberboard), MDP (medium density particleboard), plywood and timber. After reduction of these wood product residues to particles, particleboards were produced, in the UFPR Laboratory, with urea-formaldehyde resin and a target density of 0,75 g / cm? and their physical and mechanical properties were determined. Particleboards made from industrial Pinus spp. particles were also produced as control samples. C&D wood waste showed potential for use as raw material for particleboard. The properties of particleboard made of recycled timber, MDP, plywood and the mixture of the four sources of material indicated that particleboard industries could use these waste resources for the production of the inner layer of MDP products. [ABSTRACT FROM AUTHOR]

In the present study, the impact of raw material grown region on the physical, mechanical, surface properties and formaldehyde emission of the particleboard was investigated. Ailanthus altissima wood grown in Trabzon had longer fiber length and thicker fiber and trachea cell wall than those of the wood grown in Artvin. The highest amounts of lignin, ash, condensed tannin and solubility values were found in wood grown in Artvin. Ailanthus altissima wood grown in Trabzon had higher amounts of cellulose and hemicellulose than those of the wood grown in Artvin. Particleboards made from wood grown in Artvin had worse surface quality and mechanical strength properties than those of panels made from wood grown in Trabzon. On the other hand, the results showed that particleboards produced from wood grown in Artvin had lower thickness swelling and formaldehyde emision values than those of the panels produced from wood grown in Trabzon. [ABSTRACT FROM AUTHOR]

The current study aims to improve properties of particleboard manufactured from cotton (Gossium hirsutum) stalks glued with urea formaldehyde. To this aim, panel density (at three levels: 0,5; 0,65 and 0,8 g/cm³), press temperature (at two levels: 150 and 180 °C) and press closing speed (at two levels: 4 and 8mm/s) were selected as independent variables. The mechanical properties consist of modulus of rupture, modulus of elasticity and internal bonding and physical behaviors such as water absorption and thickness swelling of panels were determined. Results showed that with increasing the density of panels and press temperature modulus of rupture, modulus of elasticity and internal bonding of panels increased, while bending strengths of panels were differently affected by press closing speed compared to the internal bonding, so that with increasing the press closing speed modulus of rupture increased, but internal bonding decreased. Moreover, increasing panel density and press temperature, water absorption and thickness swelling of panels decreased. The press closing speed affected the water absorption and thickness swelling, insignificantly. [ABSTRACT FROM AUTHOR]

This study examined possible feasibility of canola (Brassica napus) straws in the production of particleboard. Three-layer experimental particleboards with density 0,7 g/cm³ were manufactured using different canola straws particle ratios (0%, 25%, 50%, 75% and 100%) and urea formaldehyde (UF) adhesive. Modulus of elasticity (MOE), modulus of rupture (MOR), internal bond strength (IB), water absorption (WA) and thickness swelling (TS) properties of the boards were evaluated and a statistical analysis was performed in order to examine possible feasibility of these straws in commercial particleboard manufacturing. The results indicated that, the addition of canola straws particle significantly improved modulus of rupture and modulus of elasticity of the panels and greatly reduced their internal bonding. Overall findings showed that most panels made from above-mentioned materials exceed the EN Standards for MOR, MOE and IB. Also, the water absorption and thickness swelling increased with increasing canola straws content in the panels. The experimental results have shown that production of general purpose and furniture grade particleboard used in dry conditions using canola straws is technically viable. The results of the study demonstrate that canola straws can be an alternative raw material source for particleboard industry. [ABSTRACT FROM AUTHOR]

The study investigated the possibility of using rape straw and expanded polystyrene for the production of low density particleboards. Particleboards with the core layer made of wood chips or rape straw, partly substituted with polystyrene (7%), were manufactured within the density range of 500 - 650 kg/ m3, and resinated with MUF resin. Our study confirmed that wood chip-expanded polystyrene (WP) and wood chip-rape straw-expanded polystyrene boards (WRP), of density reduced to 600 kg/m3, met the mechanical requirements of the subject standard for boards intended for interior design (including furniture) and used in dry conditions. However, further density reduction required an increased resination of the core layer. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the use of the reed stem in manufacturing three-layer particleboard. Variable factors were mixing ratio of reed and industrial wood particles (0:100,25:75, 50:50, 75:25 and 100:0 in the surface and middle layers), press temperature (170, 180, 190 °C) and pressing cycle time (5, 6, 7 min). Other parameters such as resin content (8% in core and 10% in faces), hardener content (2%), press closing rate (4,5 mm/min), press pressure (30 kg/cmr), board thickness (15 mm), and target density (700 kg/m3) were held constant. The physical and mechanical properties of particleboard panels including modulus of rupture, modulus of elasticity, internal bonding, water absorption and thickness swelling were determined according to the procedures of European standards. The results showed that modulus of rupture, modulus of elasticity, internal bond, water absorption and thickness swelling increased with the increase of reed particles content. The positive influence of press temperature and press time can also be seen in terms of improved physical and mechanical properties. Based on the findings of this study, we can conclude that reed stem can be used to manufacture particleboard. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

In this study, some characteristics of Rhizophora spp. particleboards bonded with Serishoom (traditional animal-based adhesive) as a phantom material was investigated. The Rhizophora spp. particleboards were fabricated in two Serishoom adhesive treatment levels (6% and 12%) with three Rhizophora spp. particle sizes (≤ 149 µm, 149 µm - 500 µm, and 500 µm - 1000 µm) at 1 g.cm-3 of the target density. The internal bond strength and the dimensional stability of the Serishoom-bonded Rhizophora spp. particleboards were improved by using the smaller Rhizophora spp. particle size and the higher Serishoom adhesive treatment level. The effective atomic numbers of the Serishoom-bonded Rhizophora spp. particleboards were determineted to be 7,56 to 7,58 by an energy dispersive X-ray, which is in good agreement with those of water and breast tissue. In addition, the density distribution profiles of the fabricated Serishoom-bonded Rhizophora spp. particleboards were determined by the Kriging method with the use Surfer8 computer software, which indicated that there was good density homogeneity throughout the Serishoom-bonded Rhizophora spp. particleboards. The results showed a potential of the Serishoom-bonded Rhizophora spp. particleboard bonded with Serishoom to be used as a phantom material. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the decay resistance of particleboards treated with nano- zinc oxide against the white-rot fungus Trametes versicolor and the brown-rot species Coniophora puteana. The nanomaterial was used for manufacturing particleboards at 5, 10 and 15% wt based on the glue dry weight. The soil block decay test was performed according to ASTM D 1413 (2007) using a 12 weeks incubation period. The results showed that all treated boards had good resistance against the decay fungi and the weight loss decreased in the samples with increasing nanomaterial loading. The threshold level of treated boards against fungal decay was obtained about 21% and 17% nano-ZnO against C. puteana and T. versicolor, respectively. Therefore, it had a positive effect on increasing particleboard resistance against the fungi. The maximum decay resistance (or minimum weight loss) occurred in the samples containing 15% zinc oxide nanoparticles. [ABSTRACT FROM AUTHOR]

The resistance of particleboards, made from wood, bamboo and rice husk, to fungi and termites was evaluated. Panels were composed of 100% wood (Eucalyptus grandis), 100% bamboo (Bambusa vulgaris), 100% rice husk (Oryza sativa), 50% wood and 50% bamboo; and 50% wood and 50% rice husk. Panels exposed to the decay the brown-rot fungus (Gloeophyllum trabeum, and the white-rot fungus (Trametes versicolor), and, in a choice feeding trial, to termites (Nasutitermes corniger). The rice husk particleboards had the highest resistance of all samples and the bamboo particleboards had the lowest resistance. T. versicolor fungi produced a larger mass loss in the particleboards than did G. trabeum. [ABSTRACT FROM AUTHOR]

The purpose of this work was to determine the effect of a thermal treatment in a vapor water saturated atmosphere, on wood particles of Laureliopsis philippiana. The particles in autoclave at 150 °C for 90 minutes and with a pressure of 430 kPa were thermally treated, the pressure generated by the evaporation of water in the sealed autoclave. The amount of extractives in soda, ethanol-toluene, cold and hot water, as well as, the percentages of cellulose, holocellulose and lignin, the pH value, the percentages of volátiles and washables acids, and buffer capacity, for both particles without and with treatment, were determined. In thermally treated particles an increase in the percentage of extractives, cellulose and volátiles and water soluble acids was found, as well as, in thermally treated particles an increment of acidity and a higher buffer capacity was found, in comparison with the particles without treatment. The thermal treatment produced a color change in the particles and a reduction in their wettability. Due to the chemical changes found in the treated particles they could present advantages in the particleboard production, allowing a better ureaformaldehyde polymerization. [ABSTRACT FROM AUTHOR]

In this research, effects of screw diameter, screw type, panel type, and end distance on lateral resistance of the joints made with drywall and sheet metal screws were studied in bagasse particleboard and the results were compared to those obtained from commercial medium density fiberboard (MDF). The accuracy of EYM in prediction of lateral resistance was then investigated. The drywall screws comprised of size 8 with coarse thread and size 10 with fine thread; the sheet metal screws comprised of size 8 and 10 with normal thread. Results indicated that lateral resistance increased with the increase in the diameter of both screw types, although not statistically significant. The lateral resistance obtained from MDF specimens was 20% more than that of bagasse specimens. Increase in the end distance also resulted in an increase in the lateral resistance. In all cases, sheet metal screws showed higher lateral resistance in comparison to those obtained from drywall screws. It can be concluded that Mode IIIs is more accurate than Mode Es in the prediction of lateral resistance in two-member screwed joints (single shear plane) for both MDF and bagasse boards. [ABSTRACT FROM AUTHOR]

Red pine cone and barks combined with red pine wood particles in various proportions were used as the raw materials for one and three layered experimental particleboard manufacturing in laboratory conditions. The pine cones and barks have higher lignin, but lower holocellulose content compare to wood. For bark-based panels, the highest MOR (2.52 MPa) corresponded to the lowest thickness swelling (9.3%) and marginally highest IB at 150°C and 8% adhesive level. The 24 hour thickness swelling (TS) values obtained in this study were lower than the required TS-EN 312 (2005) value of 14% for all bark-based boards. However, the single-layer bark-based boards demonstrated higher mechanical properties compared to three-layer boards using similar manufacturing conditions. The boards exposed to atmospheric conditions have considerably darkened (-DL) and lower surface roughness changes. Meanwhile, for single-layer cone boards, the highest MOR (4.66 MPa) was found at 150°C and 8% adhesive level, whereas the highest IB ( 1.54 MPa) and lowest TS (32.9%) were found at 150°C and 10% adhesive content. The cone-based panels had higher surface color changes (lightness and total color difference) compared to red pine wood panels. The particleboards produced using cone in the proportion of wood resulted in lower TS compared to boards made from only red pine wood. [ABSTRACT FROM AUTHOR]

In the first pan of this study, the feasibility of manufacturing resin-bonded particleboard from the recently identified Brazilian giant bamboo (Guadua magna) was evaluated. In this second part, the main goal was to study the material properties of the cement and gypsum-composites made from that bamboo species. The effect of CaCl2 addition in the physical and mechanical properties was also evaluated. Initially, the hydration test was performed to determine the inhibition index of the bamboo particles in the cement and gypsum setting. Three concentrations of CaCl2 were used to produce bamboo cementbonded particleboards (BGBP): 0%, 2% and 4%. CaCl2 was not added into bamboo gypsum-bonded particle boards (BGBP). Mechanical and physical properties were evaluated and nondestructive testing was performed as well. The inhibition index of Guadua magna in the cement or gypsum setting was classified as "low inhibition". The addition of CaCl2 at bamboo-cement boards increased the internal bonding and reduced the water absorption. Other properties were not significantly affected. The bamboo-cement boards presented higher bending strength and lower moisture content than bamboo-gypsum boards. [ABSTRACT FROM AUTHOR]

The effect of surface properties on the quality of the adhesion was evaluated for coated particleboards. Uncoated UF- and TF-bonded particleboards made using different raw materials were conditioned under 20°C and 65 % relative humidity and coated with a nitrocellulose lacquer primer by a conventional process. The interaction between the primer and surface seems to be a very important factor determining the strength of adherence. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate Eucalyptus nitens as raw material for the production of particleboards. Wood density and particle size, slenderness and pH-value were controlled. Bending strength, internal bond, density, thickness swelling and water absorption after 2 and 24 hours of particleboards with densities between 450 and 750 kg/m³, were determined. Correlations between board density and properties were calculated. The wood and particle characteristics as well as the obtained board properties proved that Eucalyptus nitens could be used for the particleboard production. As board density increases, higher mechanical properties were founded. Thickness swelling and water absorption decreased as density of particleboard increased. High correlation factors (> 0,7) between dependent variables (thickness swelling, absorption, bending strength and IB) and board density were obtained. Due to swelling is a critical property, we recommend the addition of a wax emulsion and a catalyst in the middle layer of the particleboard. [ABSTRACT FROM AUTHOR]

Cement bonded particleboards were manufactured from hornbeam (Carpinus betulus L.) wood particles. Hydration tests were carried out to determine the inhibitory index in order to characterise wood-cement compatibility. The results revealed that the mixture of hornbeam -cement can be classified as moderate inhibition. Two wood: cement ratios were applied in this study, namely 1:3 and 1:4, for the board manufacture. It was found that an increase of cement-wood ratio resulted to an increase in all, but MOR values. All properties of the boards made from 1:4 wood: cement ratio, surpassed the minimum requirements set forth by the building type HZ code. Boards were exposed to brown and white rot fungi, Coniophora puteana, Trametes versicolor respectively. Overall, both fungi failed to attack the cement-bonded boards. [ABSTRACT FROM AUTHOR]

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The objective of this paper was to examine the effect that chemical modification of raw material had on fire resistance of two panel products, namely Oriented Strand Board (OSB) and particleboard and to investigate the influence of the anhydride type. The results have shown that chemical modification affected the ignition and glowing time of two wood panel products. [ABSTRACT FROM AUTHOR]