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Soy protein adhesives are currently a hot research topic in the wood panels industry for the abundant raw material reserves, reasonable price and outstanding environmental features. But their poor water resistance, low bonding strength and intolerance to mold are major drawbacks, so that proper modification before use is essential. Glutaraldehyde is one of the more apt cross-linking agents for soybean protein adhesives, which can effectively improve the bonding strength and water resistance of the adhesive. Equally, glutaraldehyde is also an efficient and broad-spectrum fungicide that can significantly improve the anti-fungal properties of a soy protein adhesive. In the work presented here, matrix assisted laser desorption ionization (MALDI-ToF) mass spectrometry and Fourier transform infrared spectroscopy techniques were used to analyze the reaction mechanism of glutaraldehyde cross-linking soybean protein. The results confirmed the reaction of the aldehyde group with amino groups of the side chains and the amide groups of the peptide linkages constituting the skeletal chain of the protein. The laboratory plywood and particleboard bonded with glutaraldehyde-soy bean protein adhesives were prepared to determine the adhesive bonding properties, the dry strength, 24 h cold water soaking wet strength and 3 h hot water (63°C) wet strength of plywood were 2.03, 1.13 and 0.75 MPa, respectively, which satisfied the requirements of industrial production. [ABSTRACT FROM AUTHOR]

This article deals with the possibility of valorizing wood waste from grapevine cultivation of the varieties Pesecká leánka (white graft) and Frankovka modrá (red graft), grown in Slovakia. From the point of view of chemical composition, two methods (water and ethyl alcohol) were performed for the determination of extractives, acid-insoluble (Klason) lignin, and structural carbohydrates, and FTIR spectra of the grape samples were recorded. Mechanical strength, compression test parallel to the grain, and morphological properties (fiber length, width, and shape factor using a fiber tester) were carried out. The energy potential of grapevines was evaluated by determining the calorific value. According to the results, the relatively high content of carbohydrates (54.19%–55.27%) provides a prerequisite for acid or enzymatic hydrolysis to produce monosaccharides or second-generation bioethanol. FTIR spectra confirmed the higher content of lignin and cellulose in red grapes. The compression strength of grape cuttings (37.34 MPa—red; 32.34 MPa—white) was comparable to the strength of softwood species; hence, these wastes can be used for particleboard or fiberboard production. Average fiber length is comparable to non-wood species; thus, grape cutting can be used for pulp and paper production. The calorific value of grape cuttings ranged from 18.68 MJ·kg−1 (white) to 18.91 MJ·kg−1 (red), with pellets having 16.96 MJ·kg−1. The energetic potential of grape cuttings was comparable to that of other wooden materials; on the other hand, the ash content of pellets from grape cuttings (10.54%) greatly exceeded the limit given by the EN ISO 17225-1 standard, which is a significant disadvantage to pellets used for heating. [ABSTRACT FROM AUTHOR]

The reuse of natural fibers, in order to manufacture a new product, is already becoming popular due to the generation of a series of advantages in social areas. Sugarcane bagasse is a set of tangled fibers of cellulose, produced in large quantities due to increased acreage and industrialization of sugarcane resulting from public and private investments in production aimed for the alcohol industry. The aim of this study was to evaluate the feasibility of producing sheet timber manufacture from the sugarcane bagasse, analyzing mechanical strength properties. A form of metal sheet for the molding of 12 specimens based on sugarcane bagasse and industrialized resin was made. Soon after molding, specimens were submitted to a three-point bending test, with the aid of a press. The analysis of the results allowed to conclude that the tensile strength and the modulus of elasticity did not obtain the minimum values recommended by the standard. The tensile strength must be improved to allow panels to be useful for ordinary strength applications. [ABSTRACT FROM AUTHOR]

The use of agricultural biomass composites as new construction and building materials has grown rapidly in recent decades. Considering that energy consumption is one of the most important factors in production, the aim of this work is to examine how heat transfer is affected at various ratios and combinations of three-layer tea oil camellia shell (TOCS) based particleboard with the purpose of creating a mat-forming structure, which has the best physical and mechanical properties for furniture and construction use in a dry environment and consumes the least amount of energy. Additionally, it investigated how raw materials type affects the curing process of polymeric methylene diisocyanate (pMDI) using differential scanning calorimetry (DSC). According to the obtained data, the centerline temperature could reach a maximum of 125 °C after 3 min regardless of the materials or combinations, while the pMDI curing time was 100–110 °C. The results demonstrated that efficient heat transfer could help resin polymerization and improve panel properties. The effect of raw materials on the curing behavior of resin indicated that TOCS particles somehow caused more heat reactions at the curing point. It appeared that particleboard with a ratio of 40% commercial wood particles in the surface layers and 50% TOCS particles (mesh size: −3 + 14) in the core layer with a modulus of rupture (MOR) of 11.29 N/mm2 and internal bonding (IB) of 0.78 N/mm2 has the best properties and met EN 312: 2010 standard requirements for particleboard P2. [ABSTRACT FROM AUTHOR]

Date palm fiber composites with aligned, continuous fibers and epoxy matrix were prepared and mechanically characterized using micromechanical models. A hydrothermal process with microwave heating was utilized to extract the date palm frond (midrib) fibers, making the process eco-friendly as opposed to the commonly reported chemical extraction method. Single fibers were then characterized and found to have an average elastic modulus and ultimate tensile strength of 17.1 ± 1.5 GPa and 333 ± 27.4 MPa, respectively. Interfacial shear strengths ranging between 6 and 12 MPa were determined using a single-fiber pull-out test. Fibers were aligned to make uniaxial tensile samples with volume fraction ranging from 11% to 56%, elastic modulus ranging from 1.72 GPa to 9.52 GPa and ultimate tensile strengths ranging from 16.9 MPa to 43.8 MPa. All the results were found to obey "Rule of Mixtures" theory. The composite's mechanical properties are similar to or exceeding those of the commercially available wood products such as medium density fiberboard, oriented strand board, thick particle board, hard fiber board, and plywood, making the hydrothermal approach with microwave heating as a promising approach for preparation of date palm composites and further opens up similar process pathway for other natural fibers. [ABSTRACT FROM AUTHOR]

This paper aimed to analyse the mechanical and sanitary properties of artificial cast stone. To create an artificial stone product of the desired shape and design, a thermoforming process is used, during which heavy presses shape the artificial stone parts at a certain temperature. According to experimental studies, the most suitable temperature for monochromatic and patterned cast stone thermoforming is 160 °C when the material has the least bending resistance and does not react strongly to heat. It is observed that the cast stone bends more easily as the distance increases. The bending test of the glued samples made it possible to find out which of the three gluing methods is the most resistant to the forces acting on the samples during bending. The sanitary properties of the artificial stone were compared with the properties of other commonly used surfaces. In the microbiological study, suspensions of three different bacteria were spread on stainless steel, laminated particleboard and artificial cast stone, and washes were taken from 100 cm2 after 25 min. The results showed that the artificial stone after washing had the lowest number of colonies forming units per cm2, which supports the claim of excellent sanitary properties of the product. [ABSTRACT FROM AUTHOR]

The present study deals with the sound absorption performance of natural fibres from the oil palm frond (OPF), mainly considered agricultural waste. Therefore, this study aimed to investigate the sound absorption performance of OPF fibre-reinforced composite under normal incidence sound. The materials used were OPF particles and urea-formaldehyde was used as an adhesive. The particleboards were produced with three particle sizes and four target densities. The absorption coefficient of normal incidence sound (αn) was tested using an impedance tube. The effects of particle size and bulk density were also evaluated. The findings reveal thatαn exceeded 0.45 at 1000 Hz and could reach 0.95 above 3.3 kHz. This occurred when the bulk density of the OPF composite particleboards ranged between 0.3–0.4 g/cm3, and the particle size varied between medium to coarse. The results also indicated that the absorption frequency and the degree of αn significantly increased as the bulk density decreased. Therefore, OPF fibres can be used to create sound-absorbing composite particleboards. [ABSTRACT FROM AUTHOR]

Indoor formaldehyde pollution causes a serious threat to human health since it is uninterruptedly released from wooden furniture. Herein, we prepared a g-C3N4-modified TiO2 composite photocatalyst and coated it on the surface of a commercial artificial particle board with the assistance of melamine formaldehyde adhesive. The g-C3N4/ TiO2 coating was then used to degrade formaldehyde which was released in real-time from the particle board under the irradiation of visible light. The results showed that compared with pure TiO2, the g-C3N4/ TiO2 composite with a heterojunction structure had a lower band gap energy (~2.6 eV), which could effectively capture luminous energy from the visible light region. Under continuous irradiation, the g-C3N4/ TiO2 photocatalytic coating was capable of degrading more than 50% of formaldehyde constantly released from the particle board. In the meantime, the photocatalytic coating also exhibited promising catalytic stability towards various formaldehyde release speeds, air flow velocities and environmental humidities. The hydroxyl radical and superoxide radical were found to be the predominant active species which triggered formaldehyde degradation. This study provides a feasible and practical approach for the improvement in indoor air quality through photocatalyst surface engineering. [ABSTRACT FROM AUTHOR]

With the aim of providing scientific guidance for the application of spiral cutters in particleboard machining, this work studied the influence of milling parameters on milling power and power efficiency during helical milling of particleboard. And the response surface methodology was applied to optimize the milling parameters to reduce machining energy consumption and improve energy efficiency. The factors of milling depth, spindle speed and helical angle were selected as input parameters, and the mathematical models between the input parameters and the response parameters were established. Then, the significant influence of each factor and the interaction of two factors were determined by variance analysis, and the change trend of milling power and power efficiency was studied by response surface methodology. Results showed that the milling depth had the greatest impact on milling power and power efficiency, followed by the spindle speed and helical angle. An increase in the milling depth and spindle speed resulted in an increase in milling power and power efficiency, while the increased helical angle resulted in a decrease in milling power and power efficiency. The optimized values of helical angle, spindle speed and milling depth were 54°, 5650 min 1 and 1.3 mm, respectively [ABSTRACT FROM AUTHOR]

branches, acacia, polyvinyl acetate, particleboard, physical properties, mechanical properties The quality of particleboard made from broad-leaved acacia branches and PVAc adhesive was investigated. A non-factorial completely randomized design (CRD) with adhesive contents of 10%, 15%, and 20% was employed. The parameters for testing physical properties included moisture content, density, water absorption, and thickness swelling. The parameters for testing the mechanical properties were modulus of elasticity, modulus of rupture, internal bonding, and screw withdrawal resistance. The results indicates that the concentration of PVAc adhesive has a significant effect on both physical and mechanical properties of the fabricated particleboards. The LSD further test indicates that particleboard with 20% adhesive content has the highest value in strength tests and meets the Indonesian National Standard (Standard Nasional Indonesia/SNI) 032105-2006. It is suitable for non-structural indoor (interior) element. [ABSTRACT FROM AUTHOR]

Particleboard (PB) is mainly produced using urea–formaldehyde (UF) adhesive. However, the low hydrolytic stability of UF leads to poor water resistance by the PB. This research aimed to analyze the effect of hot-pressing temperatures and the addition of methylene diphenyl diisocyanate (MDI) in UF adhesive on the physical and mechanical properties of PB. The first experiment focused on pressing temperature treatments including 130, 140, 150, and 160 °C. The particles were bonded using a combination of UF and MDI resin at a ratio of 70/30 (%w/w). Furthermore, the second experiment focused on UF/MDI ratio treatment, including 100/0, 85/15, 70/30, and 55/45 (%w/w), and the particles were pressed at 140°C. All of the single-layer particleboard in this research were produced in 250 × 250 mm, with a target thickness and density of 10 mm and 750 kg/m3, respectively. This research used 12% resin content based on oven-dry weight wood shaving. The pressing time and pressing pressure were determined to be 10 min and 2.5 N/mm2, respectively. Before the tests, the board was conditioned for 7 days. When studying the effect of treatment temperature, good physical properties (thickness swelling and water absorption) and mechanical properties (MOR and MOE) were obtained at 140 °C. However, no significant difference was observed in the UF/MDI ratio between 85/15 and 55/45 using the same temperature. The increase in the MDI adhesive ratio improves the MOE and MOR values. However, the internal bond was the contrary. This study suggests that a combination of UF/MDI at a ratio of 85/15 and hot-pressing temperature at 140 °C could produce a PB panel that meets a type 8 particleboard according to the JIS A5908-2003 standard and type P2 according to the EN 312-2010 standard. [ABSTRACT FROM AUTHOR]

Reusing agro-industrial waste does not only help to mitigate environmental impact but also enables valorization through the development of new products. The aim is to enhance the physical and mechanical properties of particleboard panels produced with Eucalyptus wood and different proportions of waste products—coconut fiber (Cocos nucifera L.). Physical properties (density, water absorption, and thickness swelling) and mechanical properties (static bending and internal bond resistance) were assessed, and panels reinforced with coconut fiber showed the best qualities with higher density, greater dimensional stability, and less water absorption. Static bending resistance and internal bond resistance also increased significantly. This demonstrated the potential of achieving compatible characteristics for civil construction and furniture production through the inclusion of waste material. The impact of this research is obtained from the utilization of an important agro-industrial residue in the manufacture of permanent composites. [ABSTRACT FROM AUTHOR]

Particle boards are manufactured through a hot pressing process using wood materials (natural polymer materials) and adhesive, which find common usage in indoor decorative finishing materials. Flame-retardant particleboard, crucial for fire safety in such applications, undergoes performance analysis that includes assessing temperature distribution across its facing surface and temperature increase on the backside surface during facade combustion, yielding critical insights into fire scenario development. In this study, a compact flame spread apparatus is utilized to examine the flame retardancy and combustion behavior of particle boards, with a specific emphasis on the application of cost-effective flame retardants, encompassing aluminum hypophosphite (ALHP), an intumescent flame retardant (IFR) comprising ammonium polyphosphate (APP), melamine (MEL), and Dipentaerythritol (DPE), alongside magnesium hydroxide (MDH), and their associated combustion characteristics. The D300°C values, representing the vertical distance from the ignition point (IP) to P300°C (the temperature point at 300 °C farthest from IP), are measured using a compact temperature distribution measurement platform. For MDH/PB, APP + MEL + DPE/PB, and ALHP/PB samples, the respective D300°C values of 145.79 mm, 117.81 mm, and 118.57 mm indicate reductions of 11.11%, 28.17%, and 27.71%, compared to the untreated sample’s value of 164.02 mm. The particle boards treated with ALHP, IFR, and MDH demonstrated distinct flame-retardant mechanisms. MDH/PB relied on the thermal decomposition of MDH to produce MgO and H2O for flame retardancy, while APP + MEL + DPE/PB achieved flame retardancy through a cross-linked structure with char expansion, polyphosphate, and pyrophosphate during combustion. On the other hand, ALHP/PB attained flame retardancy by reacting with wood materials and adhesives, forming a stable condensed P-N-C structure. This study serves as a performance reference for the production of cost-effective flame-resistant particleboards and offers a practical method for assessing its fire-resistant properties when used as a decorative finishing material on facades in real fire situations.

The aim of this research work was to optimize the production of particle boards from agricultural waste (wood chips). The mechanical properties investigated were the modulus of elasticity (MOE) and modulus of rupture (MOR). The production of particle boards was investigated under the following conditions: stacking time (14-21days), resin loading (386-463 g) and amount of agro residue (154-185 g) using Box-Behnken design. Statistically significant models (p

The proportion of bark in tree trunks is in the range of ~ 10–20%. This large amount of material is currently mainly considered as a by- or even waste-product by the timber processing industry. Recently, efforts towards the use of bark have been made, e.g. as a raw material to harvest different chemical compounds or as an additive for wood particle boards. Our motivation for this work was to keep the bark in an almost natural state and explore alternative processes and applications for use. The traditional method of de-barking tree trunks by peeling was used to harvest large bark pieces. Two pieces of peeled bark were placed crosswise, with the rhytidom side (outer bark) facing each other. After different conditioning steps, bark pieces were hot pressed to panels without adding adhesives. These experiments on bark samples of different Central European tree species suggest that production of panels with species dependent properties is possible and feasible. This is a step towards producing sustainable panels by using a natural waste material, while retaining its beneficial structure and its natural chemical composition. [ABSTRACT FROM AUTHOR]

Particleboard shear walls were developed and their lateral load carrying capacities were evaluated. The shear walls were made by connecting particleboards and timber studs with polyurethane (PUR) or nails. Seven types of particleboard shear wall specimens were manufactured by varying the wood species, size of the timber studs, and number of particleboards. The size of the shear wall specimens was 2.4 m × 2.7 m, and the bottom of the shear wall was fixed to the steel frame of the test equipment using hold-downs and angle brackets. As a result, the lateral load carrying capacities of the glued particleboard shear wall (73.4 to 75.6 kN/m) were 3.2 times higher than that of the typical light-frame shear wall and higher than the experimental data of the cross-laminated timber (CLT) wall in the CLT handbook. All glued specimens failed at the hold-down and angle bracket, and there was no damage at the glue layer between a particleboard and timber studs. The shear performance with different combinations of species, stud size, and number of particleboards was not significantly different, and the shear strength of the nailed specimen was approximately 20% lower than that of the glued specimen. [ABSTRACT FROM AUTHOR]

Pyrolysis is an effective way to use abandoned furniture materials. This work dealt with solid wood, particle board, and medium density board obtained from dismantling discarded furniture as experimental materials. Slow pyrolysis was performed at a heating rate of 150 °C/h and pyrolysis temperatures of 400, 500, and 600 °C, and the products were analyzed. With the increase of pyrolysis temperature, the yield of solid products gradually decreased, while the yield of liquid products and non-condensing gases gradually increased. The carbon content in solid products reached 63.6 to 94.4%. The pyrolysis solution was acidic to weakly alkaline due to the different types and contents of adhesives in the three pyrolysis materials. Understanding the yield and characteristics of the pyrolysis products of waste furniture can provide more research directions for the recycling and utilization of these materials. [ABSTRACT FROM AUTHOR]

Agricultural resources have a great potential to be a supplement or replacement for wood, especially in countries lacking wood resources, or during times of economic turmoil of wood markets, for manufacturing panel products. Previous research has focused on various sources including wheat straw, rice straw, rapeseed, or oil palm stems, but so far hay was not considered. Hay consists of cut and dried grasses, legumes, or other herbaceous plants. It has similar structure to wheat straw with a typical waxy surface layer and poor bondability. Soaking in NaOH was employed to improve the bondability of used full-length hay, or hay particles for urea formaldehyde (UF) resin. A comparison of the physical and mechanical properties was assessed. The vertical density profile of hay panels made from treated hay reached smaller differences between surface and core density. Full-length hay panels reached the higher average values of the equilibrium moisture content (EMC), due to the structure. The bending properties of panels made of treated hay particles showed improvement, with modulus of rupture being 3.5 times higher, and modulus of elasticity 2.6 times higher than that of the untreated hay particles. Thickness swelling after 48 hours decreased for the NaOH-pretreated hay panels. [ABSTRACT FROM AUTHOR]

The effect of crack length on the fracture behavior of particleboard was investigated using the single-edge-notched bending (SENB) test method under mode I loading. The initial slope (kinit), critical stress intensity factor (KIC), specific fracture energy (Gf), and brittleness number were calculated for five different crack length/specimen width (a/W) ratios varying from 0.1 to 0.9 at intervals of 0.2. The results show that the fracture properties were significantly higher for specimens with an a/W ratio of 0.1 than for the others. However, for the critical stress intensity factor and specific fracture energy, there were no significant differences among the a/W ratios of 0.3, 0.5, and 0.7 where the crack tip was placed in the core layer of the particleboard. In general, as the a/W ratio decreased, the stiffness of the material increased, and the specimens with an a/W ratio of 0.1 showed brittle behavior. However, there was no statistically significant difference between a/W ratios of 0.5 and 0.7. [ABSTRACT FROM AUTHOR]

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]

This physical and mechanical properties of a table tennis blade made from sorghum bagasse particleboard (TTBSB-particleboard) bonded maleic acid adhesive was investigated under pressing temperature and time variations. The TTBSB-particleboard was produced via a two-stage process in this study. A pressing temperature of 170–200 °C was used to prepare the first stage for 10 min. Following this, the second stage of the TTBSB-particleboard was produced with a different pressing time of 5–20 min. The TTBSB-particleboard had a specified target density of 0.6 g/cm3 and a size of 30 cm × 30 cm × 0.6 cm, respectively. For references concerning the tested quality of TTBSB-particleboard, the JIS A 5908-2003 standard has been used. For comparison, the commercial blades of Yuguan Wooden 1011 and Donic Original Carbo Speed were tested under the same conditions. The quality of the TTBSB-particleboard was successfully enhanced by increasing the pressing temperature (170 to 200 °C) and time (5 to 20 min). As a result, the pressing condition of 200 °C and 20 min were effective in this study. The TTBSB-particleboard in this study has a greater weight than the commercial blades of Yuguan and Donic. However, the TTBSB-particleboard in this study had a ball rebound comparable to that of the Donic blade. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the applicability of sugar beet pulp (SBP) in particleboard production as a substitute for wood material. Two variants of board density, 650 kg/m3 and 550 kg/m3, containing 0%, 25% and 50% of SPB, were evaluated. During the study the following features were measured: modulus of rupture (MOR), modulus of elasticity (MOE), thickness swelling (TS) and water absorption (WA). The results showed that boards containing up to 25% of SBP meet standards for boards for general-purpose used in dry conditions. Further increases in SBP content deteriorated some of the investigated properties of the boards. [ABSTRACT FROM AUTHOR]

The article analyzes the dynamics of both the global and Ukrainian markets of woodworking products. The commodity structure of trade in wood products is analyzed by the following types: roundwood, business roundwood, fuel wood, lumber, veneer, plywood, sheet materials, chipboards, particle boards, tentative chipboards, wood fiber boards, and solid wood boards. The dynamics of both the global and Ukrainian markets of woodworking industry products is compared by the following indicators: production volume, exports, imports, domestic consumption, export orientation, and import dependence. The comparative competitive advantages of Ukrainian woodworking products with those of other countries are identified. The carried out study has shown that the development of the Ukrainian woodworking industry markets is largely in line with global trends. Among the types of woodworking products in Ukraine, the following mainly correspond to global trends: lumber, veneer, wood-based panels, chipboards, wood-fiber boards and solid wood boards, with the growth rates of production and market capacity of these types of products exceeding the global-marketed ones. The types of woodworking products that did not fully meet global trends included roundwood, business roundwood, fuel wood, plywood, and oriented strand boards, which were characterized by a decline in exports and imports, as well as fluctuations in production and market capacity. Both the global and Ukrainian markets saw a decline in sales of low-value-added wood products and a moderate increase in high value-added products. In Ukraine, only two types of woodworking products – lumber and veneer – increased their export orientation, but these products also saw a significant increase in import dependence. The strongest rates of decline in export orientation were observed in the following types of woodworking products: business roundwood (86.6%), roundwood (48.5%), wood fiber boards (39.9%), fuel wood (36.2%), and solid wood boards (25.3%), while these products also saw a significant decrease in import dependence. Taking into account the trends in the global wood products market, the ways to ensure the development of the woodworking industry in Ukraine in the postwar period are allocated. [ABSTRACT FROM AUTHOR]

Copyright of Revista Chapingo Serie Ciencias Forestales is the property of Universidad Autonoma Chapingo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Warsaw University of Life Sciences - SGGW, Forestry & Wood Technology is the property of Wydawnictwo SGGW and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Warsaw University of Life Sciences - SGGW, Forestry & Wood Technology is the property of Wydawnictwo SGGW and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Warsaw University of Life Sciences - SGGW, Forestry & Wood Technology is the property of Wydawnictwo SGGW and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Warsaw University of Life Sciences - SGGW, Forestry & Wood Technology is the property of Wydawnictwo SGGW and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annals of Warsaw University of Life Sciences - SGGW, Forestry & Wood Technology is the property of Wydawnictwo SGGW and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A hexahedron reverberation box has been developed through reverse engineering to study the reverberation time of fibrous felts in diffuse acoustic field condition. The study reinstated the frequency as a prime factor to understand the relation between noise control performance of a sample in transfer matrix method and diffused acoustic field condition. A new non-linear, bi-variant frequency dependent model was formulated through synchronization of impedance tube data and noise absorption coefficient calculated from reverberation time of the felts tested in the hexahedron box. The empirical model was validated for particle board based perforated absorber which yielded a comparable noise absorption value with a mean absolute error as low as 0.02. The reverberation box substantially reduces the size of samples for trial in nondestructive mode. The frequency dependent model for different absorber predicted the noise absorption property from calculated reverberation time (RT60), which would help in engineering specified samples for noise control. The novelty of the work lies in the fabrication of the reverberation box to work with frequency levels as low as 250 Hz i.e., above Schroeder frequency. [ABSTRACT FROM AUTHOR]

Plasma particles and waves are important observation targets in space plasmas for understanding the mechanisms of energy and momentum transfer between waves and particles because space plasmas are essentially collisionless. Multi-point observations are crucial for understanding the spatial–temporal variations of space plasmas. To realize such observations by a large number of satellites, onboard instruments should be miniaturized to reduce their required resources. This paper proposes a small amplifier for plasma particle detectors onboard satellites. This charge-sensitive amplifier converts an electron cloud emitted from the detector, for example a microchannel plate, to a current pulse that can be handled by a time-of-flight measurement circuit to determine the particle velocity and thus mass. The amplifier is realized using application-specific integrated circuit technology to minimize size. Its dimensions are estimated to be 2120 μ m × 1680 μ m , which are much smaller than those of a conventional amplifier. The response time of the proposed amplifier has a variation of less than 1.2 ns over the range of expected input levels. The amplifier can handle up to 2 × 10 7 signals per second and has a sensitivity of 1.5 V / pC at 20 ∘ C . [ABSTRACT FROM AUTHOR]

Rice husk and sawdust are abundantly available as wastes which end up in landfills. These can be utilized to produce lightweight and high strength bio-composites reinforced with jute fiber to substitute wood-based particle board (PB) for furniture production. This study aimed at producing polyvinyl acetate (PVAc) composites reinforced with jute fibers and filled with a combination of rice husks and sawdust at a ratio of 1:1 while jute fiber content was varied between 5% and 30%. Physical and mechanical properties of raw materials were characterized to ascertain their quality. The constituents were mixed and molded at room temperature. The manufactured composites were characterized by their water absorption (WA), thickness swelling (TS), density, tensile, compression, and bending strength. The results show a considerable improvement in the mechanical properties of composite when jute fiber content increased. Water absorption and thickness swelling had an inversely proportional relationship with jute fiber content due to its hydrophilic properties. On the other hand, the mechanical properties had direct proportional relationship with PVAc concentration. But above 30% PVAc concentration, the properties of the composite did not show any significant increment because above this volume fraction of PVAc, the properties tend to depend more on PVAc. [ABSTRACT FROM AUTHOR]

The European standard EN 438-2 (2019) describes a method to assess the resistance to cracking of high-pressure laminate (HPL). In the EN 438-2 setup, the samples' shrinkage at a temperature of 50 °C for 6 h is restrained by a metal clamp. The resulting tensile stress may lead to the cracking of the laminate. With the intention to gain additional insight into the parameters and influencing factors of the standard test, the resistance to cracking of 43 laminates was tested in accordance with the standard and with a prolonged testing time. Additionally, the tensile strength and shrinkage of the laminates were determined under the conditions of the standard test. The standard test uses free laminates (laminates not glued to a carrier board), so in order to correlate the results to applications that are close to real-life situations, four of the laminates were also tested when glued to carrier boards the size of furniture doors. In this full factorial test, particle board and gypsum board were used as carrier boards, UF and PVAc as adhesives, and the possible shrinkage of the laminates was adjusted by two moisture conditions of the laminates. The resistance to cracking in the standard test turned out to be mainly influenced by the composition of the laminate. Thin laminates with a pure paper backing were especially prone to cracking in the setup. Within the 6 h storage at 50 °C of the standard test, the laminates did not reach moisture equilibrium. Prolonged storage at 50 °C until equilibrium was reached (which took up to 10 days) allowed an improved differentiation of the cracking resistance, especially of thicker laminates. Four of the laminates were also tested on wooden and mineral-based carrier boards with either PVAc or UF as adhesive and two moisture contents of the laminates. The following parameters were identified as a critical combination for cracking: laminate with a low cracking resistance according to the EN 438-2 test in combination with a non-hygroscopic mineral-based carrier board, increased moisture of the laminate before being glued on the board, and the use of PVAc adhesive. [ABSTRACT FROM AUTHOR]

A commercial three-layer particleboard served as model furniture for testing pretreatment with the oyster mushroom (Pleurotus ostreatus (Jacq.) P. Kumm.) over 9-, 12-, 16-, and 20-week periods based on the effects of reducing the enzymatic resistance of component cellulose. The effects of pretreatment were assessed based on Fourier-transform infrared spectroscopy (FTIR) of the treated particleboards, wherein indexes (peaks and peak ratios) connected with parameters influencing enzymatic cellulose hydrolysis were analysed. The data were analysed in two ways: the measurement of peak heights in both primary spectra and deconvoluted spectra. The peak heights for the determination of the total crystallinity index (TCI) were measured according to narrow and broad baselines. Time and how indexes are calculated were found to be the main factors significantly influencing the values of indexes of pretreatment in most cases. Until week 9, P. ostreatus pretreatment seems to be advantageous for biofuel production, which was illustrated by decreases in the intensity of the 1735 and 1505 cm−1 peaks and A1505/A1735, A1505/A1375, A1505/A1158, and A1505/A896 ratios in addition to a reduction in crystallinity. [ABSTRACT FROM AUTHOR]

The study evaluates the performance of laboratory, single-layered particleboards made out of fructose-hydroxymethylfurfural-bishexamethylenetriamine (SusB) adhesive as a sustainable alternative. Several production parameters such as mat moisture content (MMC), adhesive amount and press time were varied and their effect on the bonding efficiency investigated. The internal bond strength (IB) and thickness swelling after 24 h of water immersion (TS) were taken as evaluation criteria for the bonding efficiency. pMDI-bonded particleboards were produced as fossil-based, formaldehyde-free reference. Particleboard testing was complemented by tensile shear strength measurements and thermal analysis. It was found that the MMC has the highest impact on the internal bond strength of SusB-bonded particleboards. In the presence of water, the reaction enthalpy of the main curing reaction (occurring at 117.7 °C) drops from 371.9 J/mol to 270.5 J/mol, leading to side reactions. By reducing the MMC from 8.7%, the IB increases to 0.61 N/mm2, thus surpassing P2 requirements of the European standard EN312. At a press factor of 10 s/mm, SusB-bonded particleboards have a similar IB strength as pMDI-bonded ones, with 0.59 ± 0.12 N/mm2 compared to 0.59 ± 0.09 N/mm2. Further research on the improvement of the dimensional stabilization of SusB-bonded PBs is needed, as the TS ranges from 30–40%. [ABSTRACT FROM AUTHOR]

One of the ways of potential improvement of the particleboard properties, especially surface quality, can be the incorporation of wood fibers to face layers. This study aimed to evaluate the selected mechanical and physical parameters of single and multi-layered particleboards with the structure modified by the incorporation of various types and amounts of wood fibers. Single, 3- and 5-layers particleboards were produced with two different types of wood fibers added to the face and core layers. The basic mechanical parameters (modulus of rupture, modulus of elasticity, internal bond, surface soundness), as well as density profile and surface roughness, have been investigated. The results have shown that the single-layer panels with fibers did not meet the standard requirements due to unsatisfactory unstable parameters, probably caused by uneven resination. The remaining panels, 3- and 5-layer, met the standard requirements, and, due to fiber incorporation, there is also potential to reduce the panel density, still meeting standard requirements. The addition of fibers from 0% to 75% in face layers leads to an increase in the modulus of rupture from 10.6 N mm−2 to 15.6 N mm−2. Depending on the fibers' type, the surface soundness can vary between 0.7 N mm−2 and 1.2 N mm−2. Five-layer panels were of similar or even higher parameters, but due to much-complicated technology, it seems unreasonable to develop this type of composite. The novelty of the conducted research is the attempt to modify the structure of particleboards by adding various amounts of two different types of fibers by mixing them with particles or adding them as separate layers and producing panels of different densities. [ABSTRACT FROM AUTHOR]

This is a bridge between circular economy issues and wood-based panels technology, especially particleboards. Because these composites contain a significant amount of non-wood raw material (10–12% thermoset resin, high hardness laminates, among others), their mechanical recycling leads to an uncontrollable reduction in produced particle size. This problem can be especially significant since the particleboards can be intended for multiple recycling due to the shortening of their service life. This research aimed to produce particles in the cycle of multiple re-milling particleboards and evaluate the selected properties of the produced particles and particleboards. Thus, the response to the following scientific problem can be given: what factors qualitatively and quantitatively influence the properties of the particleboards produced by multi-re-milled particles? The novelty of this research is the approach to recycling the raw materials from particleboards in fully controlled conditions, providing the characterization of produced particles and producing particleboards with close-to-industrial parameters, and, finally, evaluating the features of produced particleboards in the light of raw materials used. The results confirmed that subsequent mechanical recycling of particleboards, where the other panels are made entirely of second-milling particles, leads to an unprofitable and unacceptable reduction in the mechanical properties of the panels. The physical parameters, such as thickness swelling and water absorption, are improved, but this can be the result of increased content of chemical ingredients, which negatively influence the hygienic features of panels (emission of formaldehyde and total volatile organic compounds—TVOC). Further research should be directed towards estimating the optimal addition of mechanically recycled particles to particleboard production. [ABSTRACT FROM AUTHOR]

The utilization of apple tree pruning as an alternative raw material to produce cement-bonded particleboard was investigated. Experimental cement-bonded particleboards measuring 500×500×12 mm with a nominal density of 1400 kg/m3 were prepared in laboratory conditions using different ratios (100/0,75/25,50/50,25/75,0/100) of apple tree pruning chips mixed Red Pine wood chips. The following basic properties required by the TS EN 312 standards were evaluated; water absorption, thickness swelling, bending properties, and screw withdrawal strength. Results of the study indicate that the addition of apple pruning in the mix of cement-bonded particleboard significantly influences the properties tested. Mechanical properties of the tested boards decreased while absorption and thickness swelling values of the cement-bonded particleboard were increased as the portion of apple pruning in the mixture was increased. Experimental boards which include apple tree pruning up to 25 % still meet properties required by the standards for general purpose-use cementbonded particleboards. Apple tree pruning chips may be an alternative raw material for the manufacturing of cement-bonded particleboard. [ABSTRACT FROM AUTHOR]

Increased demand for wood affects its price and thus contributes to the growing interest in raw materials that can be used as a partial or total substitute for wood in the production of particleboard. One of the raw materials for the production of particleboard can be Cannabis sativa or, more precisely, hemp shives. In this work, 7 variants of panels with a density of 650 kg/m3 with 10 and 25% hemp shives substitution in different layers were produced. Particleboards containing hemp shives were characterized by lower density compared to conventional particleboards. The shares of hemp shives at the levels of 10% and 25% have a slight impact on the MOR and MOE; additional IB showed no statistically significant differences between the conventional particleboards and particleboards with a share of hemp shives. For particleboards with 25% hemp shives, a reduction in swelling was observed relative to particleboards made entirely of industrial wood particles. [ABSTRACT FROM AUTHOR]

Feasibility of olive tree pruning was studied as an alternative raw material for cement bonded particleboard. Experimental cement bonded particleboards had the dimensions of 500×500mm, a thickness of 12mm and an averaged density of 1200kg/m3. They were manufactured using two different ratios of olive pruning particles with Red pine wood in laboratory conditions. CaCl2, KCl and DARASET 580® were added to the particle cement mixture as accelerator in order to improve board properties. Water absorption, thickness swelling and bending properties of the cement bonded particleboards were evaluated using suitable standard. Results of the study showed that use of olive pruning in the production of cement bonded particleboard significantly influence the properties tested. Bending properties of the tested boards were decreased when CaCl2 was existed in the mixture while water absorption and thickness swelling values were increased. In the presence of KCl, bending strength and thickness swelling of the boards were not altered by the addition of pruning materials but bending stiffness and water absorption values were significantly improved. Use of DARASET 580® in the particle cement mixture improved thickness swelling values while decreasing bending properties. Results indicate that addition of olive tree pruning yields poor board properties which make them unsuitable for structural applications but boards with low mechanical properties may be used as other purposes such as insulation. [ABSTRACT FROM AUTHOR]

This study was performed to determine the effects of the densification process and glue type in wood material on dowel tensile performance. For this purpose, 8 mm and 10 mm diameter dowels were obtained from black poplar (Populus nigra) and Eastern spruce (Picea orientalis L.), which were densified at 50% and 75% ratios. The dowels were bonded with PVAc and D-VTKA glue separately after drilling 18 mm deep holes in the edge of the melamine-coated particleboard. The tensile performance test was determined with the Universal test device according to TS 2475 and ASTM-D 1035 principles. As a result, Eastern spruce wood had the highest tensile performance (kg/cm2), and poplar wood had the lowest (173.66). For the dowel diameter parameter, the highest value (195.11) was found at 8 mm in diameter and the lowest value (161.05) was found at 10 mm in diameter. In terms of glue type, the highest value (185.92) was seen at PVAc while the lowest value (170.24) was seen at D-VTKA. And for the densification ratios, the highest value (191.4) was determined at 75%, while the lowest value was found in control samples at (167.4). According to the wood species, densification ratio, dowel diameter and glue type interaction, the highest value was determined at Es + d75% + 10mm + PVAc as (303.5) and the lowest value was found at P + d50% + 10mm + Dv as (110). As a result, where the dowel's high tensile performance is sought, using a 10 mm diameter dowel made from 75% densified spruce wood with PVAc glue may be advantageous. [ABSTRACT FROM AUTHOR]

The compatibility of oil-palm-trunk fibers and cement was investigated. Cold-water and hydrothermal carbonization treatments were applied on the fibers, and then the hydration temperature was measured to observe the compatibility. Calcium chloride (CaCl2), as an accelerator, was added at 1.5, 3.0, 4.5 and 6.0% of cement weight. The results showed that cold-water treatment and hydrothermal carbonization of the fibers reduced the hemicelluloses and ash content, thereby increasing the compatibility. Fourier transform infra-red analysis showed that functional groups of untreated and treated fibers were almost identical, indicating that the addition of treated fibers did not interfere the hardening process of cement. The treatment of fibers resulted in reduced thermal stability of the cement-fibers mixture, and the addition of CaCl2 decreased the hydration temperature of the mixtures, indicating that the chemical accelerated the hardening of the cement-fibers mixture. The addition of 1.5% CaCl2 to the cement mixture with treated fibers was adequate to obtain a low inhibitory index. Field emission scanning electron microscopy showed that higher formation of calcium silicate hydrate and calcium carbonate was observed in the treated fibers compared to the untreated fibers. The board modulus of elasticity increased by 215% and 281% after the fibers underwent with cold-water treatment and hydrothermal carbonization, respectively. [ABSTRACT FROM AUTHOR]

This study focused on the influence of some novel scavengers on the physical, mechanical, and formaldehyde emission of particleboard produced with urea-formaldehyde resin. Three different scavengers, alizarin red sulfonate, alizarin yellow-GG, and chromotropic acid, were incorporated into the UF resin at 1, 3, 5, and 7% (by weight) loading levels based on the oven-dried weight of the resin. Other manufacturing parameters were kept constant in the production of particleboards. The results indicated that the formaldehyde emission of the particleboards significantly reduced with an increasing amount of scavengers. The lowest formaldehyde emission was found in the specimens containing alizarin red sulfonate (0.38 mg/l), followed by chromotropic acid (0.43 mg/l), and alizarin yellow-GG (0.49 mg/l), respectively, at 7 wt% loading level of the scavengers. Although the physical and mechanical properties of the particleboards decreased with the increasing content of the scavengers, they met the requirements of particleboards for interior fitments (including furniture) for use in dry conditions (P2 grade) of EN 312 standard. According to the results of technological properties and formaldehyde emission of the particleboards, it can be said that alizarin red sulfonate is the best scavenger among the investigated ones. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the biological durability of particleboard, containing silver nanoparticles (Ag-NPs) and copper nanoparticles (Cu-NPs) to Trametes versicolor, white-rot fungus of hardwoods. NPs were mixed and sprayed with applied resin, to cover wood particles volumetrically. Bio-deterioration of specimens was measured through average mass loss after 4–16 weeks of exposure to T. versicolor. The results displayed a significant impact of Ag-NPs and Cu-NPs on the antifungal resistance of particleboard. The highest resistance to fungal attack is experienced by sample containing 15% Ag-NPs with the mass loss of 0.9% for 4 weeks to 3.24% after 16 weeks of exposure to T. versicolor which was classified as a very durable sample. Maximum mass loss of 45.5% was observed for the control specimens after 16 weeks. The presence of Ag-NPs and Cu-NPs on the wood particle surface was verified by the Energy-Dispersive X-ray Spectroscopy. Scanning Electron Microscopy analysis confirmed the uniform distribution of NPs in bondline covered the surface of the wood particles properly, which seems to be an impressive barrier to fungal attack by inhibiting fungal hyphae growth. Because of the high thermal conductivity of metallic NPs, internal bonding properties of particleboard containing NPs were improved. [ABSTRACT FROM AUTHOR]

This work explores an effect of nitrogen ion implantation on the life time of WC-Co tools used in particleboard milling. Nitrogen ions with different energy of 5, 50, and 500 keV and fluence of 1e17 and 5e17 cm−2 were implanted into the surface of commercially available WC-Co composite indexable knives, using the implanters with mass-separated ion beams. Both untreated and modified samples were subjected to microstructural and durability tests. Microstructural tests involved surface observation, determination of the nature of wear and cracks, determination of element depth profiles, and phase changes occurring in the modified area. Durability tests were conducted with the use of a computerized numerical control (CNC) machining center. The tests included determination of wear curves and calculation of quantities such as cutting length, relative tool life index, standard deviation, standard error, coefficient of variation and quality index and wear increases. Additionally, a histogram of the relative durability distribution of samples implanted with N+ was determined. In this study, an attempt was made to relate the durability results with the microstructure of the knives. Tools modified with a nitrogen ion beam of 50 keV showed the best durability results. [ABSTRACT FROM AUTHOR]