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Effects of adding different boron compounds to the urea-formaldehyde resin were evaluated relative to the physical, mechanical, and other properties of medium-density fiberboard (MDF). While the chemical addition of boric acid to the urea-formaldehyde resin increased the modulus of rupture and modulus of elasticity values of MDF boards, the physical and chemical additions of other boron compounds decreased those values. While there were no significant decreases in internal bond values, the chemical addition of boric acid and borax decahydrate to ureaformaldehyde resin increased the internal bond values of MDF boards. It was observed that in both types of addition, borax pentahydrate reduced the formaldehyde emission values of MDF boards the most and also reduced the burnt area by up to 30%. When the type of addition of boron compounds to urea-formaldehyde was compared, the addition of boron compounds at the resin formation stage showed better results in the properties of MDF boards than physical addition. [ABSTRACT FROM AUTHOR]

Iso-amyl ester rosin was synthesized and investigated for its potential utilization in medium density fiberboard (MDF) production. The isoamyl alcohol, the main starting material for the synthesis of isoamyl ester rosin, was obtained through the fractional distillation of fusel oil, a byproduct of bioethanol production. The optimum condition for the iso-amyl ester rosin synthesis was determined as: rosin (165 mmol), isoamyl alcohol (413 mmol), P-TSA/rosin 1.5% (w/w), and commercial additive/rosin 0.15% (w/w). The esterification reaction was followed by FT-IR and mass analysis. For MDF production, a water-repellent material, commercial paraffin (1.5% w/w relative to the dry fiber weight), iso-amyl ester rosin (1.5% and 2.0%; w/w), and unmodified rosin (1.5% and 2.0% w/w) were separately used. In addition, fresh wood fibers, 10% w/w urea formaldehyde (UF) adhesive (relative to the total dry fiber weight), and a 25% aqueous solution of ammonium chloride (as the hardening agent for the UF adhesive, at 0.5% w/w based on the solid adhesive content) were used. MDFs underwent various physical and mechanical tests. Isoamyl ester rosin showed promising results based on the analysis. The results showed that the isoamyl ester rosin can be considered as an alternative to paraffin in sustainable and environmentally friendly MDF production. [ABSTRACT FROM AUTHOR]

Iso-amyl ester rosin was synthesized and investigated for its potential utilization in medium density fiberboard (MDF) production. The isoamyl alcohol, the main starting material for the synthesis of isoamyl ester rosin, was obtained through the fractional distillation of fusel oil, a byproduct of bioethanol production. The optimum condition for the iso-amyl ester rosin synthesis was determined as: rosin (165 mmol), isoamyl alcohol (413 mmol), P-TSA/rosin 1.5% (w/w), and commercial additive/rosin 0.15% (w/w). The esterification reaction was followed by FT-IR and mass analysis. For MDF production, a water-repellent material, commercial paraffin (1.5% w/w relative to the dry fiber weight), iso-amyl ester rosin (1.5% and 2.0%; w/w), and unmodified rosin (1.5% and 2.0% w/w) were separately used. In addition, fresh wood fibers, 10% w/w urea formaldehyde (UF) adhesive (relative to the total dry fiber weight), and a 25% aqueous solution of ammonium chloride (as the hardening agent for the UF adhesive, at 0.5% w/w based on the solid adhesive content) were used. MDFs underwent various physical and mechanical tests. Isoamyl ester rosin showed promising results based on the analysis. The results showed that the isoamyl ester rosin can be considered as an alternative to paraffin in sustainable and environmentally friendly MDF production.

An Image Processing Based Scrub Tester (IPBST) was used to imitate the effect of household chemicals on furniture and decoration elements. For this purpose, 8 mm-thick, bright white, acrylic coated medium density fiberboard (MDF), polyvinyl chloride coated MDF, MDF lam ready-to-use sheets, and cellulosic, polyurethane, acrylic, and water-based paint applied MDF sheets were used. Carbon fiber patterned decorative coating was applied to the prepared sample surfaces using the water transfer printing and ultraviolet printing methods. The surfaces of the samples were scrubbed with various household chemicals in accordance with the Turkish Standard TS EN ISO 11998. In the image processing phase, the images before and after scrubbing were first converted to hue, saturation, and value color space. The relationship between the abrasion measurement method of the proposed IPBST and the abrasion data obtained from the stereo microscope device was examined using the Pearson Correlation analysis. The relationship between both abrasion test methods was positive, very strong, and significant (0.81). Thus, the IPBST can be used as an alternative to industrial test devices as it obtains similar data. [ABSTRACT FROM AUTHOR]

Melamine-impregnated paper decorated medium-density fiberboard (MIPMDF) is the main board used for wooden furniture materials in China, and the formaldehyde released from the board and furniture products is harmful to human beings and is a wide concern. This paper aimed to pay attention to the formaldehyde emission of MIP-MDF and its furniture products. This study utilized a 1 m³climatic chamber to measure the formaldehyde emission of MIP-MDF and nightstand made of MIP-MDF in relation to the time and load factors. According to the results, in the 2 to 24 h stage, the emission of formaldehyde in the nightstand made of MIPMDF materials changed significantly, and the overall trend showed a changing trend of first increasing and then declining. The formaldehyde emission of MIP-MDF stabilized after 40 h, while the formaldehyde emission of the nightstand stabilized after 60 h. As time passed, the formaldehyde emission changes of MIP-MDF and nightstand were almost the same. The formaldehyde emission of MIP-MDF and nightstand has a specific positive correlation with the carrying load. With increased carrying loads, the formaldehyde emission tends to increase, but the degree of influence gradually decreases with the addition of the carrying loads. [ABSTRACT FROM AUTHOR]

Optimum application values of the Water Transfer Printing (WTP) technique were determined on various wood-based panel surfaces. For this purpose, 8-mm-thick, glossy white, acrylic-coated medium-density fiberboard (MDF) panels (high gloss panels), polyvinyl chloride (PVC)-coated MDF panels, MDF Lam ready-to-use panels, and cellulosic, polyurethane, acrylic, and water-based paint applied MDF panels were used. An automatic immersion system with pool was designed and produced. A 30-μm-thick carbon patterned WTP film was applied on sample panel surfaces prepared with the help of this device at four immersion angles (0°, 15°, 30°, and 45°), four immersion speeds (50 cm/min, 100 cm/min, 150 cm/min, and 200 cm/min), and four immersion times (5 to 10 s, 20 to 30 s, 50 to 60 s, and 80 to 90 s). The optimum parameters of the WTP technique regarding the temperature and relative humidity of the application environment, water temperature, laying method, dissolution time, amount of activator, spray gun angle and tip clearance, air pressure, as well as immersion angle, speed, and time were determined using the measurement and observation method. According to the optimum parameters obtained in the study, the WTP technique was successfully applied to all wood-based panel surfaces. [ABSTRACT FROM AUTHOR]

This study determined the deflection performance of wooden cabinet doors during opening and closing by using different material types, opening-closing angle, and load force. The independent variables consisted of material type, opening-closing angle, and load force, and the dependent variable was determined as deflection value. Medium density fiberboard (MDF) and particleboard (PB), both melamine faced, were used as two different material types. Opening and closing angles and directions of forces were performed as directed in BS EN 16122 (2012) and TSE EN 9215 (2005) and the doors were loaded by forces of 300N, 375N and 450N. The factors affecting deflection value and the interaction between them were investigated by multivariate analysis of variance. The results showed that the material type, angle, load force, and the mean between the material type and load force was significant. As the loading force increased, the deflection value increased. As the moisture increased, the deflection value increased, and as the material density increased, deflection value decreased. The adequacy of models was evaluated by the R-square (R²) and Adjusted R-square (Adj-R2) values. The results for these values were 88.23% and 86.58%, respectively. [ABSTRACT FROM AUTHOR]

Medium density fiberboard (MDF) is widely utilized in furniture production. Most MDF in such applications has a surface laminate layer. The lamination process improves the physical and mechanical properties of the boards. The temperature, press time, and pressure values applied during the lamination process affect such properties. In this work, the lamination process was carried out using a constant temperature (180 °C), four different press times (18, 20, 22, and 24 s), and three different pressures (25, 30, and 35 kg/cm²). The raw weight of the decor paper was 90 g/m² and UF and MF glues were used in its production. The properties of the laminated panels were then determined for each variation. In general, the water absorption and thickness swelling properties were improved at the lower pressure and higher press times. The internal bonding strength exhibited a linear change at different press times depending on increasing pressure values, whereas the changes in the bending strength and modulus of elasticity in bending were not statistically significant. It was concluded that the BS increased with rising pressure in the short-term lamination process and that the effect of the pressure on the BS declined with increasing press time. [ABSTRACT FROM AUTHOR]

The growing interest in wood accessories has focused scientific research attention on wood cutting with small diameter tools. A problem that may arise when drilling wood is the phenomenon of wandering - when the hole is not made in the designed place. The difficulty in studying small diameter drill holes (0.5 mm to 0.9 mm) is due to the difficulty of automatic measurement. The development of an appropriate methodology may allow for the observation of this phenomenon without the need for highclass hardware and expensive software. This article presents the results of tests carried out on nearly 500 samples made of various wood-based materials (high-density fiberboard (HDF), medium-density fiberboard (MDF), chipboard, and plywood) in terms of the usefulness of the OpenCV computer vision library for the determination of wandering. [ABSTRACT FROM AUTHOR]

Physical, mechanical, and formaldehyde emission properties were studied for medium density fiberboard (MDF) produced with oak (75%) and pine (25%) fibers that had been mechanically refined in the presence of calcite particles. The calcite slurry was prepared at two levels of solids, 1.5% and 3% (10 and 20 kg·m-3). Chips were cooked for 4 min at 185 °C, under 8 bar vapor pressure in an Andritz defibrillator. 1.8% liquid paraffin, 0.72% ammonium sulphate solution, and 11% urea-formaldehyde were added by percentage based on oven-dried wood fibers in the blowline at the exit of the defibrator. The fibers were dried to 11% moisture content. MDF boards (2100 mm × 2800 mm × 18 mm) were created using a continuous hotpress process. The addition of calcite in the course of MDF production resulted in improved physical properties, such as thickness swelling (ThS 24 hours) and water absorption (WA 24 hours). MDF boards prepared with calcite exhibited higher internal bond (IB), modulus of rupture (MOR), and modulus of elasticity (MOE). Resistance to axial withdrawal of screw also was increased by addition of 3% calcite. In addition, the lowest levels of formaldehyde emission were observed for MDF prepared with calcite at the 3% level. [ABSTRACT FROM AUTHOR]

Oxidized starch (OS) adhesives with a balance between their adhesion and disintegration properties were prepared by controlling the degree of oxidation and modifying the cross-linker type and level to replace ureaformaldehyde (UF) resins for easy recycling of medium density fiberboard (MDF). Four molar ratios of H2O2/starch, two types of cross-linker, i.e., blocked-pMDI (B-pMDI) and citric acid (CA), and three levels of the crosslinkers were employed to tailor the performance of the OS adhesives. The OS reacted with the isocyanate groups from the B-pMDI to form amide linkages, while it formed ester linkages by reacting with the CA. The resulting B-pMDI/OS-bonded MDF had better physical and mechanical properties than the CA/OS-bonded MDF, with comparable adhesion (0.34 MPa) to UF resins and ten times greater degree of fiber disintegration than UF resins. The combination of a 0.5 molar ratio OS with 7.5 wt% of BpMDI produced MDF exhibiting an optimal balance between adhesion and disintegration, suggesting that such OS adhesives could someday replace UF resins in manufacturing and recycling of MDF without formaldehyde emission. [ABSTRACT FROM AUTHOR]

The main objective of this study was to investigate the flame retardant (FR) efficiency of melamine pyrophosphate (MP) with added layered double hydroxide (LDH) in medium density fiberboards (MDFs) to be used as building decorative materials. The thermal degradation, FR efficiency, and combustion properties of MDF were analyzed by Fourier transform infrared spectra (FTIR), thermogravimetric analysis (TGA), limiting oxygen index (LOI) test, and cone calorimetric test. The TGA results showed that the combination of MP and LDH led to a lower decomposition temperature than the pure MP and pure LDH. The LOI results showed that the LOI values increased with the addition of the FRs. The cone calorimetric results showed that the addition of four proportions (1:1, 2:1, 1:2, and 1:3) of the compounds into MDF can clearly decrease the peak heat release rate (PHRR) and mean heat release rate (MHRR). The results indicated that the MP and LDH compounds have a synergistic effect to improve the flame retardancy and smoke suppression in the MDFs. The combination of MP and LDH in a 1:1 ratio under 10 wt% FR addition has the best flame retardant efficiency in the MDFs.

Bio-based flours derived from distiller's dried grains with solubles (DDGS), Osage orange seed meal (OOSM), or defatted commercial soybean meal flour-Prolia (PRO) were employed as adhesives with Eastern redcedar (Juniperus virginiana L.) wood (ERC) to fabricate composite wood panels (CWPs). OOSM and DDGS were defatted, milled, and screened prior to use. PRO was employed as provided. DDGS, OOSM, or PRO flour were mixed dry with ERC wood to make CWPs using the following conditions: molding temperature of 185 °C, ERC particle sizes of ≤75 µm to 1700 µm, pressure of 5.6 MPa, and employed in flour dosages of 10% to 75%. Flexural properties of DDGS and OOSM flour-ERC composites were similar to composites fabricated using PRO as the resin/adhesive. The dimensional stability properties (water absorption and thickness swelling) of all composites were similar. ERC CWP properties satisfied several European Committee Industry Standards for commercially acceptable CWPs in terms of their flexural properties but were inferior in terms of thickness swelling when subjected to water immersion testing. Surface roughness and color analysis of CWPs were also conducted. Statistical correlations between surface roughness and color properties and the composition of the CWPs were conducted. ERC CWPs were found to have termite resistance. [ABSTRACT FROM AUTHOR]

Photocatalytic carbonized medium density fiberboard (MDF) was prepared by one-step carbonization with titanium tetraisopropoxide (Ti-tip) as a TiO2 precursor. Anatase TiO2 was formed at carbonizing temperatures of 600 to 800 °C. However, at > 900 °C, most crystalline TiO2 was rutile. Ti-tip-treated carbonized MDF (c-MDF) showed outstanding formaldehyde reduction performance with complete removal of formaldehyde from the chamber in 1 to 3 days. However, with non Ti-tip-treated c-MDF, formaldehyde remained after 20 days. No toluene was detected after 3 h on 50% Ti-tip-treated c-MDF, while toluene was continuously detected with other samples (10% and 5% Ti-tip-treated c-MDF, and untreated c-MDF). After 9 h ultraviolet exposure, toluene was completely reduced on 10% and 50% Ti-tip-treated c-MDF; reduction was only 20% on untreated c-MDF. In addition, c-MDF/TiO2 prepared at 800 and 900 °C had significantly higher photocatalytic performances compared to those obtained at lower carbonization temperatures. Based on the results, the combination of 10% Ti-tip treatment and carbonizing at 800 °C provided the optimum photodegradation capacity for formaldehyde and toluene. [ABSTRACT FROM AUTHOR]

This paper examined the effect of machining parameters on surface roughness of medium density fiberboard (MDF) machined using a computer numerical control (CNC) router. The machining parameters such as spindle speed, feed rate, depth of cut, and tool diameter were examined for milling. The experiments were conducted at two levels of spindle speeds, four levels of feed rates, two levels of tool diameters, and two levels of axial depths of cut. The surface roughness values of MDF grooved by CNC were measured with stylus-type equipment. Statistical methods were used to determine the effectiveness of the machining parameters on surface roughness. The influence of each milling parameter affecting surface roughness was analyzed using analysis of variance (ANOVA). The significant machining parameters affecting the surface roughness were the feed rate, spindle speed, and tool diameter (p < 0.05). There was no significant influence of axial depth of cut on the surface roughness. The surface roughness decreased with increasing spindle speed and decreasing feed rate. The value of surface roughness increased with the increase of tool diameter. [ABSTRACT FROM AUTHOR]

The use of different mineral material types and contents in medium density fiberboard (MDF) production was investigated. Three different minerals (sepiolite, dolomite, and perlite) and five different ratios (3%, 6%, 9%, 12%, and 15%) were used according to the oven-dry wood fiber weight. These minerals were homogeneously added as powder between the wood fibers. Some physical, mechanical, limit oxygen index (LOI), and thermogravimetric analysis (TGA) tests of the boards were conducted. The mineral fillers negatively affected the physical properties such as water absorption (WA), thickness swelling (ThS), and mechanical properties such as modulus of rupture (MOR), modulus of elasticity (MOE), and internal bond (IB). However, LOI and TGA test results showed a positive effect on combustion resistance depending on the type and rate of mineral fillers. [ABSTRACT FROM AUTHOR]

Crude oil as a non-renewable resource is creating new challenges in many industrial sectors. Unsteady costs of crude oil at present and expected increases in the future are due to its limited availability as a finite resource, and these costs negatively impact the industry for wood-based panels, which use petrochemical resins in binding agents. Furthermore, wood panels that are conventionally bonded using urea formaldehyde diffuse formaldehyde into the surrounding air. To achieve independence from petrochemical products and harmful formaldehyde emissions, alternatives for their substitution are in demand. An alternative approach is the enzymatic activation of lignin located on the surface of thermomechanical pulp (TMP) fibers. The present study shows the results of internal bond strength (DIN EN 319 1993), modulus of rupture (DIN EN 310 1993), and thickness swelling (EN 317 2003) of medium-density fiberboards (MDF) bonded with laccase-mediator-system (LMS). Caffeic acid (CA), 4-hydoxy benzoic acid (HBA), and vanillic alcohol (VAl) were used as mediators. The physical and technological properties of MDF, such as internal bond strength, modulus of rupture, and thickness swelling, mostly fulfilled the European standards.

The properties of medium density fiberboard (MDF) derived from different manufacturing plants were compared. Each plant provided 5 full-sized (2440 by 1220 mm) 155-grade panels that were tested according to ANSI A208.2-2009. None of the panels met the recommended value for Internal Bond (IB). Mean values for Thickness Swell (TS) were all significantly different, with one manufacturer below the standard. Three manufacturers exceeded the recommended face Screw Withdrawal Resistance (fSWR) values, one was equal to it, and one failed. Three manufacturers exceeded the edge SWR (eSWR) standard, and the remaining two fell below. Two manufacturers met the standard for Modulus of Rupture (MOR), and only one manufacturer failed to meet the Modulus of Elasticity (MOE) requirements. Linear Expansion (LE) was evaluated for a RH change from 50 to 90%. The panels made with pMDI-resin consistently had some of the highest mean values for MOR, MOE, fSWR, and IB and exhibited good performance in the TS test.

Laccase, an enzyme capable of degrading lignin, has become an effective agent for green processing and has great significance for the protection of the environment and the development of a low-carbon economy. In this work, wood fibers were selected as the raw material, and with activation by a laccase-mediator system, lignin was changed to a natural adhesive material, and the high temperature/high pressure method was used to prepare medium density fiberboard (MDF). The bonding mechanism was explored with measurements of Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), environmental scanning electron microscope (ESEM), and X-ray diffraction (XRD). It was found that the self-adhesive effect was realized through esterification, hydrogen bonding, polycondensation, coupling, and a Schiff base reaction, among which coupling and polycondensation were the primary reactions. The chemical bonds between the MDF interior and surface varied because of the mobility of the lignin during the reaction.

This study analyzes the critical static friction coefficient (μ0) and the static friction coefficient (μ) between work-piece and rubber belt during sanding medium density fiberboard (MDF) and particle board (PB). The purpose is to provide theoretical support for improving design techniques of sanding machine and choosing appropriate rubber belts for sanding. The results indicate that μ0 is a constant that can be calculated by maximum sanding force (sFMax) and maximum normal force (nFMax). Besides, there is an exponential relationship between intensity of pressure (P) and μ when work-piece is relatively static on a rubber belt. Among all sanding parameters, git size (G) has the greatest influence on μ. In single-factor experiment, we found that the smaller the nFMax is, the greater the μ is (for same rubber belts), but the variation rates of μ and nFMax are coincident. Six types of rubber belts are adopted, and the average μ of No. 1 and No. 4 are greater than others, but average μ of all the belts are lower than μ0, so when use such six types of rubber belts, a hold-down device or vacuum chuck should be equipped on the sanding machine. Patterns of rubber belts have some impact on μ, and appropriate patterns on the surface of rubber belts contribute to higher μ.

The proper parameters of sanding with an abrasive sanding machine are significant to reduce energy consumption and to improve processing efficiency and quality. The influences of grit size (G), feed speed (U), sanding speed (V), and sanding thickness (Ts) on the sanding force (sF), normal force (nF), arithmetic mean deviation of profile (Ra), power consumption (P), and power efficiency (ε) were analyzed by the orthogonal method in this study. Fuzzy synthetic evaluation (FSE) was adopted to evaluate sF, P, and Ra comprehensively and to determine the optimum sanding parameters. For both medium density fiberboard (MDF) and particle board (PB), G has the greatest impact on Ra. For MDF, Ts and G have great impacts on sF, G is also the significant factor affecting nF, whereas the significant factors affecting P are U and V. For PB, G, U, and Ts have great impacts on sF, while G and Ts are the significant factors for nF. Significant factors for P are V and Ts. For MDF and PB, when the weight vector (sF, Ra) is (0.3, 0.7), the optimum schemes are G80U3m/minV8.04,9.38,10.74m/sTs0.2,0.3mm and G80U3m/minV9.38m/sTs0.2 mm, respectively, and when (sF, Ra) is (0.7, 0.3), the optimum schemes are G80U3,3.72m/minV6.69,8.04,9.38m/sTs0.2 mm and G80U3m/minV8.04,9.38m/sTs0.2 mm, respectively. Additionally, when the weight vector (P, Ra) is (0.3, 0.7) or (0.7, 0.3), the optimum scheme is G100U2.52m/minV5.35m/sTs0.1 mm.

Distillers dried grains with solubles (DDGS) were employed as a biobased resin/adhesive. DDGS were defatted with hexane, ball ground, and screened prior to use. DDGS flour was mixed dry with Paulownia wood (PW) to make composites using the following conditions: temperature of 150 to 195 °C, PW particle sizes of ≤ 75 to 1700 µm, pressure of 2.1 to 5.6 MPa, and using DDGS dosages of 10 to 100%. Molded composites were evaluated for their flexural properties. Composites were examined with Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and X-ray diffraction. The best flexural properties were obtained from composites containing 50% DDGS and 50% PW, using 180 to 250 µm PW particles, pressed at 5.6 MPa, and employing 185 °C. Flexural properties of DDGS-PW composites were similar to composites fabricated using soybean flour (Prolia) as the resin/adhesive. Dimensional stability properties (water absorbance and thickness swelling) of DDGS-PW and Prolia-PW composites were similar. DDGSPW composite properties satisfied several European Committee Industry Standards for fiberboards in terms of flexural properties but were inferior in terms of thickness swelling properties. [ABSTRACT FROM AUTHOR]

Effects of type of wood, number of blades, and depth and width of cutting were evaluated relative to the noise level during the machining of wooden materials in a spindle moulder. Lombardy poplar, Oriental beech, and medium density fibreboard (MDF) materials, at the thickness levels of 6 mm, 12 mm, 18 mm, 25 mm, or 30 mm, were planed for 20 min for each variable at the feed rate of 5 meters per min and at the cutting depth of 1 mm, 2 mm, or 3 mm with one or four blades. During machining of the samples, the noise levels were measured using a noise level meter. According to the data obtained, the highest noise level connected to the type of materials was measured in the machining of poplar wood, followed by that of beech wood and MDF. As the thicknesses of the materials were increased, increases up to 9 dBA of the noise level were measured. Moreover, machining the materials with one blade instead of four and with a cutting width of 1 mm instead of 3 mm increased the noise level by 2 dBA and 6 dBA, respectively. [ABSTRACT FROM AUTHOR]

Refining is a critical step in the manufacturing of medium-density fiberboard (MDF). To ensure fiber quality and control of the energy consumption during refining, proper production parameters, such as feeding screw revolution speed (SR), accumulated chip height (CH), opening ratio of the discharge valve (OV), and content of Chinese poplar (CP), are vital. These parameters were monitored and recorded in an MDF mill to investigate the relationships between the parameters and the fiber quality and energy consumption. In this study, fuzzy models of the fiber quality and the energy consumption during refining were established based on subtractive clustering and an adaptive neuro-fuzzy inference system (ANFIS). The fiber quality and energy consumption models demonstrated high prediction accuracy because their predictive mean relative errors were as low as 4.14% and 6.72%, respectively. The errors of fiber quality were optimized using the simulated annealing method, and the input parameters were obtained. Based on the energy consumption model, the minimum energy consumption was 41.51 kWh/t, on the premise of the minimum requirement of fiber quality. This study can be a guideline for MDF production management to improve fiberboard quality and reduce energy consumption. [ABSTRACT FROM AUTHOR]

The machining mechanisms in milling for medium-density fiberboard (MDF) and wood-plastic composites (WPC) are reviewed in this article. The study focuses on milling tool wear, chip formation mechanisms, processing stability, and machined surface roughness. The influence law of cutting parameters (cutting speed, feed rate, and cutting thickness), tool materials and geometry (rake angle, relief angle, and size parameters), temperature, and other factors on tool wear and machined surface roughness were considered. Concrete measures to improve tool life and machined surface quality are summarized as well as an online monitoring system of tool wear and machined surface roughness. Future research of tool wear and surface quality in milling wood-based materials is proposed to provide important references for wood-based materials researchers. [ABSTRACT FROM AUTHOR]

This paper presents the energy consumption differences during the edge milling of various board materials (medium-density fiberboard (MDF), medium-density fiberboard with single-sided lamination (MDF-L), and spruce edge-glued panel (SEGP)). The edge milling was carried out with various parameters: feed rate (4, 8, and 11 m/min); cutting speed (20, 30, 40, and 60 m/s); and blade type (tungsten carbide HW1, HW2, and HW1 coated with CrTiN (HW1 + CrTiN)). The results indicated that the increase in the cutting speed and feed rate cause the increase in cutting power. The highest cutting power values were observed with the milling of MDF; slightly lower values were observed with MDF-L, and the lowest values were observed with SEGP. Very similar cutting power values during milling were noted with HW1 and HW2 blades, whereas milling with the HW1 + CrTiN resulted in slightly higher values (e.g., 1% higher). [ABSTRACT FROM AUTHOR]

Wet-formed particleboard panels were made using cellulose nanofibrils (CNF) as the bonding material. The effects of panel density, CNF addition ratio, particle size, and pressing method on the nail and face screw withdrawal strength, water absorption (WA), and thickness swelling (TS) were investigated. The nail and face screw withdrawal strength increased with an increased panel density and CNF addition ratio. Mixed-size particles were favorable for better face screw withdrawal strength. The WA decreased while TS increased with increased panel density. The WA decreased with increased CNF addition ratio. The effect of CNF addition ratio on the TS was influenced by an interaction effect of the particle size, density, and pressing method. Smaller wood particles and the constant thickness (CT) pressing method were better for both WA and TS performance. All of the high- and medium-density panels failed to satisfy the standard requirements for face screw withdrawal strength. For lowdensity panels, those manufactured with mixed-sized particles all satisfied the standard requirements; those manufactured with large particles required at least 15% CNF to meet the standard, and those manufactured with small particles required at least 20% CNF to achieve the standard requirements. None of the panels met the standard TS requirement (< 8%). [ABSTRACT FROM AUTHOR]

Synergic effects of different fire retardant compounds and zinc borate on wood-plastic composites filled with polypropylene (PP) and mediumdensity fiberboard (MDF) waste fibers were investigated. For this purpose, zinc borate, synergic compounds (antimony trioxide, ammonium phosphate, and magnesium hydroxide), and a coupling agent, i.e., maleic anhydride-grafted polypropylene (MAPP), were used in the production of wood-plastic composites (WPCs). The composite samples were characterized in terms of the burning rate and limiting oxygen index (LOI) analyses, thermal gravimetric analysis (TGA), and differential scanning calorimetry (DSC) along with mechanical tests, i.e., flexural properties, tensile properties, elasticity modulus, and impact strength. It was found that the synergic influence of the combination of zinc borate, antimony trioxide, and magnesium oxide on WPCs increased the heat resistance according to the burning rate, LOI, TGA, and DSC tests. Also, the mechanical properties of the WPCs decreased slightly, but their elasticity modulus increased. [ABSTRACT FROM AUTHOR]

The influence of rake angle, cutting speed, and uncut chip thickness on cutting forces and chip morphology in medium density fiberboards orthogonal cutting was investigated. With regard to the normal cutting force and the feed force recorded, there were important variations when machining conditions were modified, or when some tool characteristics were changed. The findings led to the conclusion that there was a close relationship between the cutting conditions and chip formations as well as the cutting forces. Such forces were found to be particularly sensitive to changes in uncut chip thickness, as well as showing dependence on the cutting speed of the tools in orthogonal cutting.

The radon absorption performance was determined and compared for different types of carbonized boards to establish effective carbonized boards. Moreover, the absorption mechanism of carbonized boards was investigated by specific surface area and pore size in each of the carbonized boards. The radon absorption performance was ranked in the following order: ash (87%), medium-density fiberboard (MDF, 83%), oriented strand board (OSB, 82%), particleboard (PB, 77%), and plywood (PW, 67%). The correlation between radon absorption capacity and surface area or pore volume showed that a higher surface area or pore volume had higher radon absorption performance. However, the highest surface area and pore volume was detected on carbonized MDF, which had a radon absorption performance that was 5% less than carbonized ash board. Therefore, the surface area and pore volume as well as other factors affected the absorption performance. [ABSTRACT FROM AUTHOR]

The level of relative humidity is one of the key parameters in evaluating indoor air quality and comfort. In principle, humidity can be kept more uniform over time by use of materials that adsorb moisture from the air reversibly. This study was conducted to investigate the effect of loess treatment and carbonization on the hygric performance of mediumdensity fiberboard (MDF). The loess treatment was conducted with different sizes of loess particle prepared by a high-pressure homogenizer. After loess treatment on the surface of the MDF, it was carbonized at high temperature (600 °C). Loess is an abundant mineral high in Si content, which has high moisture absorption capacity, which remained after the carbonization process. The study also found that the loess treatment positively affected the hygric performance of carbonized MDF (c-MDF). The hygric performance of c-MDF almost doubled after the loess treatment compared with the non-treated c-MDF. However, the nano conversion of loess did not influence the hygric performance. Loess-treated carbonized MDF could be used as a humidity controller in buildings. [ABSTRACT FROM AUTHOR]

Flax shive and hemp hurd residues were characterized, and the feasibility of manufacturing three-layered particleboards was evaluated using 2.5% and 5% polymeric diphenyl methane diisocyanate resin loadings. The flax shive and hemp hurd residues had lower bulk densities and higher aspect ratios compared with the wood residues. Their higher aspect ratios offered greater overlap in bonding, which led to consistently higher bending properties that exceeded the American National Standards Institute (ANSI) requirements for low-density (LD2) particleboard and, in some cases, medium-density (M2) particleboard. Because of their particle geometry, the flax shive and hemp hurd particleboards also showed minimal linear expansion with changes in the moisture content at 20 ± 3 °C and between 50% and 90% relative humidity. The high absorption capacity of the flax shive and hemp hurd residues resulted in higher thickness swell and water absorption properties than the wood residues. The results indicated that low-density flax shive and hemp hurd particleboards (500 to 620 kg/m3) can be manufactured using isocyanate resin quantities as low as 2.5% to produce panels that conform to ANSI specifications with a greater mechanical performance than that of wood residue particleboards. [ABSTRACT FROM AUTHOR]

The main objective of this study was to investigate the flame retardant (FR) efficiency of melamine pyrophosphate (MP) with added layered double hydroxide (LDH) in medium density fiberboards (MDFs) to be used as building decorative materials. The thermal degradation, FR efficiency, and combustion properties of MDF were analyzed by Fourier transform infrared spectra (FTIR), thermogravimetric analysis (TGA), limiting oxygen index (LOI) test, and cone calorimetric test. The TGA results showed that the combination of MP and LDH led to a lower decomposition temperature than the pure MP and pure LDH. The LOI results showed that the LOI values increased with the addition of the FRs. The cone calorimetric results showed that the addition of four proportions (1:1, 2:1, 1:2, and 1:3) of the compounds into MDF can clearly decrease the peak heat release rate (PHRR) and mean heat release rate (MHRR). The results indicated that the MP and LDH compounds have a synergistic effect to improve the flame retardancy and smoke suppression in the MDFs. The combination of MP and LDH in a 1:1 ratio under 10 wt% FR addition has the best flame retardant efficiency in the MDFs. [ABSTRACT FROM AUTHOR]

The effect of temperature in the range from 25 ºC to 175 ºC on the bending performance of plywood and medium density fiberboard (MDF) has been studied with the ultimate purpose of optimizing the post-processing using radio frequency heating and improving the quality of the final products. Static 3-point bending tests were conducted on a universal testing machine inside a computer-controlled chamber. Results show that the bending strength (MOR) and modulus of elasticity (MOE) of plywood and MDF decrease with the increase of the temperature from 25 ºC to 175 ºC. The bending strength of plywood and MDF decreases with the increase of the exposure time. However, the effects of exposure time on MOE of plywood and MDF are not obvious. Plywood and 2.6 mm thick MDF show a typical elasto-plastic behavior, while 12 mm thick MDF does not exhibit any plastic behavior. It is recommended that the post-processing procedure should be completed within 15 minutes for both MDF and plywood.

Fire retardant particles (guanylurea phosphate and boric acid) with a morphological characteristic of large crystal or fine microsphere, were respectively applied to wood fibers to make medium density fiberboard (MDF). The effects of particle size of the fire retardant on the combustion performance of the resulting MDF samples were determined using a thermogravimetric (TG) analyzer and cone calorimeter (CONE). The scanning electron microscopy and laser particle size analysis showed that the microspheric particles of fire retardant had a mean size of approximately 20 µm, which was smaller than the crystal (260 um). Incorporation of the fire retardant either in the crystal or microsphere shape reduced the weight loss of the resulting MDF, as evidenced by the TG analysis and the CONE test; the release rate and total amount of both the heat and smoke were apparently inhibited as compared to the untreated MDF samples. Treatments caused an increase in both the ignition time and charring ratio of the MDF. Compared with the fire retardant crystals, the fine microspheric particles exhibited greater ability in inhibiting the release of heat and smoke through the combustion processes.

Severe shortage of suitable wood for Medium Density Fiberboard (MDF) production makes it necessary to consider using uncommon and non-conventional raw materials such as agricultural residues. In order to demonstrate the suitability and the potential of two agricultural residues (cotton and corn stalks), laboratory MDF boards were produced. Three press temperatures (170, 180 and 190 ºC) were used. Test samples were prepared from the boards after conditioning at 65% RH and 21 ºC, and all tests were performed according to relevant EN standard methods. The results indicated that the MOR and MOE of boards produced from corn stalks were higher than those from cotton stalks, by almost 25%. However significant difference was not observed for internal bonds of boards. Thickness swelling of MDF boards from corn stalks was lower than cotton stalks. Comparing the results obtained with the strength of boards produced from hardwoods showed similarity between corn stalks and wood, but the strength of MDF boards from cotton stalks was lower. However, the results almost satisfied the EN 622-5;1997 requirement.

The objective of this research was to investigate the utilization of olive mill sludge (OMS) as an alternative to wood in the manufacture of the medium density fiberboard (MDF). The MDF panels were manufactured using standardized procedures that simulated industrial production at the laboratory. Six panel types were made from various mixtures of hardwood fiber/dried OMS flour, 100/0, 90/10, 80/20, 70/30, 60/40, and 50/50 (by weight) percents, respectively. With increasing OMS flour content, the flexural properties of the panels, modulus of rupture and modulus of elasticity, decreased by 31.0% and 29.2% as compared to panels without OMS flour, respectively. However, the water resistance was improved by the addition of the OMS flour up to 20 wt % content. For example, the thickness swelling and water absorption values of the panels containing 20% OMS flour were 17.3% and 59.5%, while they were found for the panels without OMS flour as 21.5% and 75.6%, respectively. The findings obtained in the study showed that the OMS was capable of serving as lignocellulosic raw material in the manufacture of the MDF.

A long standing problem in the manufacture of wheat-straw based composites with cost-effective formaldehyde-based resins is their poor water resistance as demonstrated by their large water thickness swell. In this study, wheat straw based medium density fiberboards were manufactured using 3 resin/wax systems: a melamine-urea-formalde-hyde resin with either low or high wax content, and a phenol-formal-dehyde resin with low wax content. The flexural properties, internal bond strength, and thickness swell of the resulting composites were evaluated and compared according to ASTM methods. The three MDF compos-ites passed the requirements for MDF in interior application, except for the MDF manufactured with the aminoplastic resin and low wax content that failed to provide acceptable thickness swell. Using the phenolic resin in combination with low wax content resulted in a higher grade MDF composite, grade 120, than with the aminoplastic and high wax content. This study demonstrates that wheat straw based MDF manu-factured with cost-effective aminoplastic and phenolic resins can have flexural properties, internal bond strength and thickness swell perfor-mance above the requirements from the American National Standards Institute.

Crude oil as a non-renewable resource is creating new challenges in many industrial sectors. Unsteady costs of crude oil at present and expected increases in the future are due to its limited availability as a finite resource, and these costs negatively impact the industry for woodbased panels, which use petrochemical resins in binding agents. Furthermore, wood panels that are conventionally bonded using urea formaldehyde diffuse formaldehyde into the surrounding air. To achieve independence from petrochemical products and harmful formaldehyde emissions, alternatives for their substitution are in demand. An alternative approach is the enzymatic activation of lignin located on the surface of thermomechanical pulp (TMP) fibers. The present study shows the results of internal bond strength (DIN EN 319 1993), modulus of rupture (DIN EN 310 1993), and thickness swelling (EN 317 2003) of medium-density fiberboards (MDF) bonded with laccase-mediatorsystem (LMS). Caffeic acid (CA), 4-hydoxy benzoic acid (HBA), and vanillic alcohol (VAl) were used as mediators. The physical and technological properties of MDF, such as internal bond strength, modulus of rupture, and thickness swelling, mostly fulfilled the European standards. [ABSTRACT FROM AUTHOR]

The overall objective was to use waste plywood and medium density fiberboard (MDF) to manufacture a new type of board. The dimensional stability of board was improved by mechanical inhibition between laths along the thickness direction. Its modulus of rupture (MOR) and dimensional stability were tested to determine whether it satisfied the Chinese national standard. The innovational points lie in the treatment to improve dimensional stability and raw materials. The MOR of board manufactured with MDF was superior to that manufactured with plywood, although the MOR of MDF was lower than the MOR of plywood. The IT and DT of new manufactured boards decreased more than 33.48% compared to the raw materials. Besides, the warpage and thickness variation tended to be stabilized with cyclical tests continuing. This result indicated that the treatment of mechanical inhibition between laths along thickness direction could improve the dimensional stability of boards. In addition, MDF was a suitable raw material for the new board. [ABSTRACT FROM AUTHOR]

The properties of medium density fiberboard (MDF) derived from different manufacturing plants were compared. Each plant provided 5 full-sized (2440 by 1220 mm) 155-grade panels that were tested according to ANSI A208.2-2009. None of the panels met the recommended value for Internal Bond (IB). Mean values for Thickness Swell (TS) were all significantly different, with one manufacturer below the standard. Three manufacturers exceeded the recommended face Screw Withdrawal Resistance (fSWR) values, one was equal to it, and one failed. Three manufacturers exceeded the edge SWR (eSWR) standard, and the remaining two fell below. Two manufacturers met the standard for Modulus of Rupture (MOR), and only one manufacturer failed to meet the Modulus of Elasticity (MOE) requirements. Linear Expansion (LE) was evaluated for a RH change from 50 to 90%. The panels made with pMDI-resin consistently had some of the highest mean values for MOR, MOE, fSWR, and IB and exhibited good performance in the TS test. [ABSTRACT FROM AUTHOR]

An equivalent strain method was used to analyze and determine material relaxation properties for specimens from particleboard, high density fiberboard, and medium density fiberboard. Cantilever beams were clamped and then deflected to 11 m and held for either 2 h or 3 h, while the load to maintain that deflection was measured vs. time. Plots of load relaxation for each specimen showed similar load relaxation vs. time even though there were some slight differences in the maximum load per sample. Three models were developed to fit the relaxation data. The first model was a simple log decrement. This simple log model used only one variable, the relaxation coefficient, to describe the relaxation behavior as the log of time. The log decrement model was marginal at best in modeling the relaxation data. The second and third models, however, used equivalent strain methods. The second model assumed a combined linear-elastic spring and a Kelvin-Voigt spring-dashpot model. The third model used a combination of a linear-elastic spring (linear strain) element, a Kelvin-Voigt (spring-dashpot, visco-elastic strain) element, and a dashpot (permanent strain) element for its total configuration. Both equivalent strain models provided excellent correlations for the two lengths of time used for this series. Estimated mechanical and relaxation, or creep properties, were determined from the equivalent strain method using cantilever beam equations. [ABSTRACT FROM AUTHOR]

This study investigated the pull off strengths of various laminated medium density fiberboards (MDFs). The surface roughness of the MDF, adhesive type, and veneer type were all studied. Polyvinylacetate (PVAc), urea formaldehyde (UF), and gluten were used as the adhesives for beech, pine, and oak veneers. There were a total of 216 experimental specimens that were tested according to the principles specified in the TS 5339 (1987) standard. According to the statistical analyses of the data obtained from the tests, surface roughness, veneer species, and adhesive type all affected the pull-off strength of the laminated MDF. The highest pull-off strength (2.88 N/mm2) was obtained with the MDF unsanded with 120-grit abrasive and laminated with PVAc adhesive and pine veneer. The lowest pull-off strength (1.60 N/mm²) was obtained with the unsanded MDF laminated with PVAc adhesive and oak veneer. [ABSTRACT FROM AUTHOR]

It is preferred to perform conformity assessment of wood-based panels on the whole panel without cutting it down to smaller pieces. The modulus of elasticity, a mechanical property of wood, was determined by longitudinal vibration testing with the full-size panel, and the results were compared with results of tests of prismatic beams. The Brancheriau's correction coefficient was used to compensate for errors from cross-sectional dimension variations and errors from Poisson's ratio. Longitudinal excitation of the panels along the length was shown to be successful in evaluating the modulus of elasticity. However, strong correlations obtained from plate and beam comparisons along the width of the panels are promising. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate the effect of the addition of bamboo laminas of the species Dendrocalamus giganteus to three-layer medium density particleboard (MDP). These laminas were glued onto both the top and the bottom of each panel. With the manufactured panels laminated with bamboo, mechanical tests based on the Brazilian Standard ABNT NBR 14810 were carried out to determine the modulus of rupture (MOR) in static bending and the tensile strength parallel-to-surface. These mechanical tests were realized in particleboards of eucalyptus and in reinforced particleboard, both produced in the laboratory. The modulus of rupture and tensile strength parallel-to-surface of the laminated MDP had values close to those that have been reported. The reinforcements increased the values of these studied properties. Nevertheless, this fact indicated the possibility to produce a stronger MDP using bamboo lamina as surface layers. These results show the possibility of using coatedbamboo MDP for utilization in large spans, for example, in flooring for mezzanines with finish on both sides, and for robust furniture as bookshelves, beds, tables, etc. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of almond shell powder content as an extender, as well as the effects of varying paraffin contents, temperature, and press time on the properties of medium-density fiberboard. Response surface methodology (RSM) based on a five-level, four-variable central composite rotatable design was applied to evaluate the effects of independent variables on the modulus of rupture (MOR), internal bonding (IB), and thickness swelling (TS) of medium-density fiberboard. Mathematical model equations were derived from computer simulation programming to optimize the properties of the panels. These equations, which are second-order response functions representing MOR, IB, and TS, were expressed as functions of four operating parameters of panel properties. Predicted values were found to be in agreement with experimental values (R2 values of 0.93, 0.90, and 0.90 for MOR, IB, and TS, respectively). The study showed that RSM can be efficiently applied in modeling fiberboard properties. It was found that almond shell powder maintained the MOR, IB, and TS at desirable levels up to 10.6% as an extender in the resin. Using 1.7% paraffin as a sizing agent, a press temperature of 158 °C, and a duration of 6.43 min had the highest impact on the improvement of the studied properties of medium-density fiberboard. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effects of panel type and panel thickness on moment resistance of L-type corner joints and deflection characteristics of four-member cabinets. Three different wood based panels, namely particleboard (PB), medium density fiberboard (MDF), and okoume (Aucoumea klaineana) plywood (PW) were utilized in two different thickness levels for constructing the four-member cabinets. All corner joints and cases were assembled with 4 x 50 mm screws without adhesive. The four member cabinets were tested under static load by supporting at three points. Furthermore, moment resistances of the same type jointed L-type corner joints were tested under static compression and tension loads. Test results indicated that the highest stiffness values were observed with 15 mm PW. This showed that 15 mm plywood could be used instead of 18 mm PW. 16 mm PB and MDF cabinets yielded higher stiffness values than those of 18 mm MDF, PW, and PB. Test results also indicated that 15 mm and 16 mm thick panels can have nearly the same stiffness as 18 mm thick panel. [ABSTRACT FROM AUTHOR]

This study analyzes the critical static friction coefficient (μ0) and the static friction coefficient (μ) between work-piece and rubber belt during sanding medium density fiberboard (MDF) and particle board (PB). The purpose is to provide theoretical support for improving design techniques of sanding machine and choosing appropriate rubber belts for sanding. The results indicate that μ0 is a constant that can be calculated by maximum sanding force (sFMax) and maximum normal force (nFMax). Besides, there is an exponential relationship between intensity of pressure (P) and μ when work-piece is relatively static on a rubber belt. Among all sanding parameters, git size (G) has the greatest influence on μ. In single-factor experiment, we found that the smaller the nFMax is, the greater the μ is (for same rubber belts), but the variation rates of μ and nFMax are coincident. Six types of rubber belts are adopted, and the average μ of No. 1 and No. 4 are greater than others, but average μ of all the belts are lower than μ0, so when use such six types of rubber belts, a hold-down device or vacuum chuck should be equipped on the sanding machine. Patterns of rubber belts have some impact on μ, and appropriate patterns on the surface of rubber belts contribute to higher μ. [ABSTRACT FROM AUTHOR]