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In this study, the effect of using olive stone residues (OSR) on some properties of particleboard was investigated. For this purpose, particle boards were manufactured from particles of white poplar (Populus Alba L.), which were partially substituted with OSR particles in amounts of 10 %, 20 % and 30 %. In addition, boards containing 30 % OSR, which had previously been chemically modified with NaOH solution, were produced. Phenol formaldehyde adhesive was used in the production of the boards. Chemical properties of wood and OSR particles (pH, alcohol benzene solubility, amount of ash), physico-mechanical properties (density, moisture content thickness swelling, modulus of rupture, modulus of elasticity and internal bond strength) and formaldehyde emission values of boards were determined. Water absorption and thickness swelling values were generally decreased with the increase in the use of OSR. When the effect of OSR usage on bending strength, modulus of elasticity, and perpendicular tensile strength values were examined, a decrease in the values was observed except for the 10 % OSR usage ratio. As a result of the application of alkali pretreatment, an increase in thickness swelling values was observed, while the values of mechanical properties increased. Scanning electron microscopy (SEM) analysis results showed more spaces between particles with an increasing OSR usage ratio. Formaldehyde emission values decreased with the increasing amount of OSR. Formaldehyde emission values increased slightly with the application of alkaline pretreatment. Based on the findings of this study, we can conclude that OSR can be used at particularly low ratio in particleboard production., U istraživanju je ispitan učinak iskorištenja ostataka koštica masline (OSR) na neka svojstva ploča iverica. Za potrebe eksperimenta izrađene su ploče od iverja drva bijele topole (Populus alba L.) koje je djelomično zamijenjeno košticama masline u količini od 10, 20 i 30 %. Osim toga, izrađene su ploče s 30 % ostataka koštica masline prethodno modificiranih otopinom NaOH. Pri izradi ploča upotrijebljeno je fenol-formaldehidno ljepilo. Utvrđena su kemijska svojstva drva i ostataka koštica masline (pH, topljivost u smjesi alkohola i benzena, sadržaj pepela) te fizičko-mehanička svojstva (gustoća, sadržaj vode, debljinsko bubrenje, modul loma, modul elastičnosti i čvrstoća raslojavanja) i vrijednosti emisije formaldehida proizvedenih ploča. Upijanje vode i debljinsko bubrenje u osnovi je smanjeno zbog povećanja udjela ostataka koštica masline. Pri ispitivanju utjecaja udjela ostataka koštica masline na čvrstoću na savijanje, modul elastičnosti i vlačnu čvrstoću okomito na ploču uočeno je smanjenje tih vrijednosti ploča, osim pri udjelu ostataka koštica masline od 10 %. Kao rezultat alkalne predobrade uočeno je povećanje vrijednosti debljinskog bubrenja, ali i povećanje vrijednosti mehaničkih svojstava ploča. Rezultati pretražne elektronske mikroskopije (SEM) pokazali su da se s povećanjem udjela ostataka koštica masline povećava prostor između čestica. Vrijednosti emisije formaldehida smanjile su se s povećanjem udjela ostataka koštica masline, ali su blago porasle uz alkalnu predobradu. Na temelju rezultata ovog istraživanja možemo zaključiti da se ostatci koštica masline u malom udjelu mogu iskoristiti u proizvodnji ploča iverica.

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 (67.8ᵒ), while the roughest surface (14.20 µm (Ra), 68.05 µm (Ry), and 50.02 µm (Rz)) and highest contact angle (96.9ᵒ) 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.

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 (67.8ᵒ), while the roughest surface (14.20 µm (Ra), 68.05 µm (Ry), and 50.02 µm (Rz)) and highest contact angle (96.9ᵒ) 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.

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 (67.8ᵒ), while the roughest surface (14.20 µm (Ra), 68.05 µm (Ry), and 50.02 µm (Rz)) and highest contact angle (96.9ᵒ) 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.

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 (67.8ᵒ), while the roughest surface (14.20 µm (Ra), 68.05 µm (Ry), and 50.02 µm (Rz)) and highest contact angle (96.9ᵒ) 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.

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.

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.

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.

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.

Shrinkage and swelling characteristics of wood as a hygroscopic material affect negatively its effective utilization for a variety of applications. Heat treatment is widely used for minimizing the negative effects of volumetric swelling and shrinkage of wood. The present study aims to develop artificial neural network (ANN) models for predicting volumetric swelling and shrinkage of heat treated woods. For this purpose, wood samples were subjected to heat treatment at varying temperatures (130, 150, 170 and 190 ºC) for varying durations (2, 4, 6 and 8 h). Experimental results have showed that volumetric swelling and shrinkage of wood decreased by heat treatment. Then, neural networks models capable of predicting the swelling and shrinkage of the treated woods were developed based on the resulting data. It was seen that ANN models allowed volumetric swelling and shrinkage of such woods to predict successfully with a limited set of experimental data. This approach was able to predict volumetric swelling and shrinkage of wood with a mean absolute percentage error equal to 2,599% and 2,647% in test phase, respectively. The developed models might thus serve as a robust tool to predict volumetric swelling and shrinkage with less number of experiments.

Shrinkage and swelling characteristics of wood as a hygroscopic material affect negatively its effective utilization for a variety of applications. Heat treatment is widely used for minimizing the negative effects of volumetric swelling and shrinkage of wood. The present study aims to develop artificial neural network (ANN) models for predicting volumetric swelling and shrinkage of heat treated woods. For this purpose, wood samples were subjected to heat treatment at varying temperatures (130, 150, 170 and 190 ºC) for varying durations (2, 4, 6 and 8 h). Experimental results have showed that volumetric swelling and shrinkage of wood decreased by heat treatment. Then, neural networks models capable of predicting the swelling and shrinkage of the treated woods were developed based on the resulting data. It was seen that ANN models allowed volumetric swelling and shrinkage of such woods to predict successfully with a limited set of experimental data. This approach was able to predict volumetric swelling and shrinkage of wood with a mean absolute percentage error equal to 2,599% and 2,647% in test phase, respectively. The developed models might thus serve as a robust tool to predict volumetric swelling and shrinkage with less number of experiments.

Shrinkage and swelling characteristics of wood as a hygroscopic material affect negatively its effective utilization for a variety of applications. Heat treatment is widely used for minimizing the negative effects of volumetric swelling and shrinkage of wood. The present study aims to develop artificial neural network (ANN) models for predicting volumetric swelling and shrinkage of heat treated woods. For this purpose, wood samples were subjected to heat treatment at varying temperatures (130, 150, 170 and 190 ºC) for varying durations (2, 4, 6 and 8 h). Experimental results have showed that volumetric swelling and shrinkage of wood decreased by heat treatment. Then, neural networks models capable of predicting the swelling and shrinkage of the treated woods were developed based on the resulting data. It was seen that ANN models allowed volumetric swelling and shrinkage of such woods to predict successfully with a limited set of experimental data. This approach was able to predict volumetric swelling and shrinkage of wood with a mean absolute percentage error equal to 2,599% and 2,647% in test phase, respectively. The developed models might thus serve as a robust tool to predict volumetric swelling and shrinkage with less number of experiments.

Shrinkage and swelling characteristics of wood as a hygroscopic material affect negatively its effective utilization for a variety of applications. Heat treatment is widely used for minimizing the negative effects of volumetric swelling and shrinkage of wood. The present study aims to develop artificial neural network (ANN) models for predicting volumetric swelling and shrinkage of heat treated woods. For this purpose, wood samples were subjected to heat treatment at varying temperatures (130, 150, 170 and 190 ºC) for varying durations (2, 4, 6 and 8 h). Experimental results have showed that volumetric swelling and shrinkage of wood decreased by heat treatment. Then, neural networks models capable of predicting the swelling and shrinkage of the treated woods were developed based on the resulting data. It was seen that ANN models allowed volumetric swelling and shrinkage of such woods to predict successfully with a limited set of experimental data. This approach was able to predict volumetric swelling and shrinkage of wood with a mean absolute percentage error equal to 2,599% and 2,647% in test phase, respectively. The developed models might thus serve as a robust tool to predict volumetric swelling and shrinkage with less number of experiments.