Properties Of Medium Density Fibreboard Research Articles

Geometric changes of TMP fibres due to thermo-hydrolytic disintegration of waste MDF evaluated by three fibre analysers

ABSTRACT Thermo-hydrolytic disintegration of medium-density fibreboard (MDF) is a promising method for recovering fibres. This process, however, may affect the geometry and size distribution of the applied fibres initially obtained by thermomechanical pulping (TMP), and thus, the properties of MDF produced thereof. Optical methods based on image acquisition are increasingly common for geometrical characterisation to assess fibre quality. In this study, we analysed the size distribution of recovered fibres (RF) obtained by thermo-hydrolytic disintegration of urea–formaldehyde-bonded waste MDF and subsequent hammer-milling by using three optical fibre analysers, FibreShape Pro, QICPIC and Valmet FS5, while comparing them to virgin fibres (VF). The analysers use different evaluation methods and therefore gave different absolute values. Thus, size distributions could not be directly compared. Nevertheless, the results provided an indication of the changes that occurred during the manufacturing and recycling process. The RF displayed a similar fibre geometry to the VF, in spite of process-related shortening. Mean fibre length and length-based distribution of the VF were always greater than those of the RF, while fibre width of the hammer-milled RF was slightly greater than that of the VF. The analysers, however, provided substantially different results, especially between FibreShape Pro and QICPIC, although the general tendencies observed for the process-related changes were consistent. It can be concluded that the thermo-hydrolytic disintegration applied to the UF-bonded MDF did not cause any substantial changes in fibre geometry (i.e. fibre shortening). All fibre analysers are capable of detecting these changes, but the absolute values provided can vary widely between the instruments.

Investigation of Physical and Mechanical Properties of Medium Density Fibreboards (MDF) Produced from Iron Tree (Casuarina equisetifolia L.) Wood

Bu çalışmada, Demir ağacı (Casuarina equisetifolia L.) odunu kullanılarak, kuru life oranla 1.17 mol üre formaldehit (ÜF) reçinesi (%12.5), katı parafin (%1.5) ve %10’luk amonyum klorür solüsyonu (%1,30) eklenerek MDF üretim hattında 0.694 g/cm³ yoğunlukta levhalar üretilmiştir. Bu levhaların fiziksel ve mekanik özellikleri incelenmiştir. Fiziksel özelliklerden levhaların yoğunluğu 0.694 g/cm³, kalınlığına şişme değerleri 2 ve 24 saat için sırası ile %2.53 ve %6.01 olarak ölçülmüştür. Mekanik özelliklerden eğilme mukavemeti 35.20 MPa, elastikiyet modülü 2982.8 MPa ve çekme mukavemeti 0.42 MPa ölçülmüştür. Bu çalışmadan elde edilen verilere göre, Demir ağacından (Casuarina equisetifolia L.) üretilen MDF levhaların fiziksel ve mekanik özellikleri çekme mukavemeti hariç TS EN standardının üzerinde ölçülmüştür.

The effect of partial substitution of polyphosphates by aluminium hydroxide and borates on the technological and fire properties of medium density fibreboard

ABSTRACT Aim of this study was to evaluate the effect of aluminium hydroxide and borates, separately or combined with ammonium polyphosphate (APP), upon the technological and fire properties of medium density fibreboard (MDF). Fire resistant MDF was fabricated in the laboratory from Scots pine (Pinus sylvestris L.) fibres bonded with a high molar ratio melamine-urea-formaldehyde resin. Overall, 24 h-swelling and water absorption properties of the treated boards were improved or remained unchanged compared to untreated ones. On the contrary, the internal bond strength (IB) of the fibreboards was significantly reduced up to 48%. The fire properties of the fibreboards were assessed by the determination of limiting oxygen index and cone calorimetry. As expected, the tested fire-retardants improved the fire resistance of the boards. Furthermore, the combination of aluminium hydroxide with ammonium polyphosphate considerably upgraded the fire retardancy while the incorporation of borates into APP showed much weaker effects.

Oil Palm Empty Fruit Bunches (EFB): Influence of Alkali and Acid Treatment on the Mechanical Properties of Medium Density Fibreboard (MDF)

Empty Fruit Bunches (EFB) are abundance residues from palm oil plantation was recognised as a potential material for manufacture such as particleboard and medium density fibreboard (MDF). The objective of this study is to identify and assess the potential effects of chemical treatment and concentration on the mechanical and bonding properties of MDF from EFB oil palm fibres. The EFB fibres were treated at 0.2, 0.4, 0.6 and 0.8% of sodium hydroxide (NaOH) and acetic acid (CH?COOH), and the fibres were used in the MDF production. Mechanical test included modulus of rupture (MOR), modulus of elasticity (MOE) and internal bonding (IB) were conducted. Between the chemical treatment and the concentration, the chemical types used had a more prominent effect compared to the concentration. This study also shows that both treatments resulted in different MDF performance, where acid acetic fibre produced better bending and bonding properties. The optimum condition was 0.4% for NaOH and 0.6% for CH?COOH to produced panels with good strength and better dimensional stability. Such sample for 0.4% NaOH had 17.9 MPa, 1297 MPa and 0.48 MPa, and for 0.6% CH?COOH had 22.1 MPa, 1641 MPa and 0.56 MPa, for MOR, MOE and IB, respectively.

Influence of varying density on the mechanical and physical properties of Medium Density Fibreboard (MDF) containing kenaf

Generally, Medium Density Fibreboard (MDF) is made from rubberwood, wood fiber and pine wood with combination of non-woody plant and agricultural residues in producing furniture and laminated floor. The usage of kenaf as main production of MDF had attracted attentions from researchers due to its anatomy of physicals and high content of organic compound namely are cellulose, hemicellulose and lignin. Due to these advantages, kenaf showed the huge potential in producing MDF with the bigger scale of production. In present study, nine (9) panel boards of MDF with sizes of 350 (length) x 350 (width) x 12 (thickness) in millimetres were fabricated based on three (3) different target densities started from 0.7 g/cm3 to 0.8 g/cm3. A total of three (3) samples for each target density were prepared for the measurements. The proportion of 65:15 which was described as ratio of kenaf particles to urea formaldehyde (UF) were selected and measured from the total volume of panel board. Testing of Modulus of Rupture (MOR), Modulus of Elasticity (MOE), Internal Bonding (IB) and Thickness Swelling (TS) were conducted in the present study. All measurements were carried out according to the BS EN 310:1993, BS EN 319:1993 and BS EN 317:1993. Results showed the increment of MOR, MOE and decrement of IB and TS were associated with increment of target density. Thus, target density of 0.8 g/cm3 for MDF is the best selection due to high MOR and MOE and low IB and TS corresponding to other two (2) target densities. The decrement of panel thickness also capable to achieve high density associated with high MOR and MOE. Therefore, the significant outcome shows the kenaf plant have the potential as alternative material to produce the Medium Density Fibreboard (MDF).

The Effect of Vermiculite Usage on Surface Properties of Medium Density Fibreboard

In this study, the effects of vermiculite of volcanic minerals usage on the surface properties were investigated in medium density fiberboard (MDF) production. The test boards were produced using the dry method with 12% urea formaldehyde resin. Additions of 10%, 15%, 20% and 30% vermiculite were used based on the full dry fiber weight. Surface roughness, color and gloss values of both surfaces of the obtained boards were determined. Based on the results, the ratio of vermiculite increased, roughness values on the surfaces increased. The roughness values in the bottom surface of the produced boards were determined to be higher than the top surface. With the use of 30% vermiculite, the average minimum surface roughness (Ra) was found to be 8.65 μm on the upper surfaces and 15.44 μm on the lower surfaces. It has been found that total color change and brightness are improved by the increase of vermiculite usage and the color change on the bottom surface is found higher. In short, the use of vermiculite in the production of MDF negatively affects the surface roughness and discoloration of the boards, but it has been found to positively affect the gloss

The flexural properties of medium density fibreboard overlaid with veneer from three species of wood

Aesthetic and strength are not easy to be combined in one wood composite product. This research aimed at combining both utilizing MDF overlaid with avocado, mahogany and pine veneer. Seven types of MDF composite plywood (comply) were designed using two adhesive types of Epoxy and Isocyanat. The adhesive spread weight was 250 g m-2. Cold compression was conducted within 3 hours with the pressure of 15 kg cm-2. The research results showed that flexural modulus (MOE) and flexural strength (MOR) of PMI comply (pine veneer, isocyanat adhesive) increased respectively by 129.5% and 75.9% when compared to MDF. This research recommends that MDF comply may be utilized for the structural and non-structural purposes.

Technological properties and fire performance of medium density fibreboard (MDF) treated with selected polyphosphate-based fire retardants

ABSTRACT The objective of the work was to evaluate the efficacy of two new polyphosphate-based fire retardants (FRs) and one commercial product named Siriono® on the fire performance and physical–mechanical properties of medium density fibreboard (MDF) fabricated in the laboratory from Scots pine (Pinus sylvestris L.) wood. The fibres were treated with aqueous solutions of fire retardants, at 12% loading (dry salt on dry wood), and bonded with a melamine urea formaldehyde (MUF) adhesive. The physical and mechanical properties of panels were assessed using the European standards, whereas their fire performance was evaluated using an in-house method and the Cone calorimeter. In overall, the chemicals added enhanced the fire and smoke properties of the panels to varying degrees. Critical FR parameters such as peak heat release rate (peak HRR), total heat release (THR) and total smoke production (TSP) were significantly improved in the FR-treated panels, as exhibited in cone calorimeter tests. However, the internal bond strength of treated panels largely decreased by the addition of fire retardants, while thickness swell and water absorption negatively affected to a significant extent. In contrast, the formaldehyde release of the panels was considerably decreased at the E1 class level, with the incorporation of the polyphosphate-based additives.

Effect of Alkaline Pre-Treatment on the Surface Modification of Napier Grass Fibres for the Properties of Medium Density Fibreboard (MDF)

Effect of Alkaline Pre-Treatment on the Surface Modification of Napier Grass Fibres for the Properties of Medium Density Fibreboard (MDF)

비스-디메틸아미노메틸 포스핀산과 알킬렌디아미노알킬-비스-포스폰산 유도체에 의해 처리된 중밀도 섬유판의 연소특성

This study was performed to test the combustive properties of Medium Density Fibreboards (MDFs) treated with chemicals of the bis-(dimethylaminomethyl) phosphinic acid (DMDAP), N,N-dimethylethylenediaminomethyl-bis-phosphonic acid (DMDEDAP), piperazinomethyl-bis-phosphonic acid (PIPEABP), and methylpiperazinomethyl-bis-phosphonic acid (MPIPEABP). MDFs were painted in three times with 15 wt% solution of the bis-(dimethylaminomethyl) phosphinic acid and alkylenediaminoalkyl-bis-phosphonic acids at the room temperature, respectively. After drying MDF treated with chemicals, combustive properties and volatile organic compounds (VOCs) contents were examined by the cone calorimeter (ISO 5660-1), test for flame retardant (NEMA Notice No. 2012034), and gas chromatography (KS M ISO 11890-2), respectively. It was indicated that the MDFs treated with chemicals showed the longer time to combustion time (CT) = (442~492) s than that of virgin plate by reducing the burning rate except for CT treated with DMDAP. In adition, the MDFs treated with chemicals showed both of the higher char area (44.33~61.33) kg/kg and char length (10.33~11.67) cm than those of virgin plate. Especially, the MDFs treated with chemicals showed the higher mean volatile organic compounds (VOCs) (0.188~0.333) g/L than that of virgin plate within the prescribed limits. Thus, It is supposed that the combustion-retardation properties were improved by the partial due to the treated chemicals in the virgin MDF.

알킬렌디아미노알킬-비스-포스폰산으로 처리된 중밀도섬유판의 연소특성

이 연구에서는 피페라지노메틸-비스-포스폰산, 메틸피페라지노메틸-비스-포스폰산, N,N-디메틸렌디아미노메틸-비스-포스폰산으로 처리된 중밀도섬유판의 연소성을 시험하였다. 15 wt%의 알킬렌디아미노알킬-비스-포스폰산 수용액으로 중밀도섬유판에 3회 붓칠하여 실온에서 건조시킨 후, 콘칼로리미터(ISO 5660-1)를 이용하여 연소 특성을 고찰하였다. 그 결과, 알킬렌디아미노알킬-비스-포스폰산으로 처리한 시험편이 무처리 시험편과 비교하여 연소 억제성을 향상시켰다. 특히 알킬렌디아미노알킬-비스-포스폰산으로 처리한 시험편은 연소속도 감소에 의하여 무처리 시험편과 비교하여 각각 지연된 착화시간(148 s~116 s), 긴 불꽃소멸시간(633 s~ 529 s), 그리고 낮은 총열방출률(<TEX>$61.1MJ/m^2{\sim}67.0MJ/m^2$</TEX>)을 나타내었다. 따라서 알킬렌디아미노알킬-비스-포스폰산으로 처리한 시험편은 중밀도섬유판 시험편에 비하여 낮은 연소성질을 나타내었다. 그러나 피페라지노메틸-비스-포스폰산으로 처리한 시험편은 무처리 시험편과 비교하여 높은 최대열방출률(<TEX>$75.7kW/m^2$</TEX>)을 나타내었다. This study was performed to test combustive properties of medium density fibreboard (MDF) plates treated with piperazinomethyl-bis-phosphonic acid (PIPEABP), methylpiperazinomethyl-bis-phosphonic acid (MPIPEABP), and N,N-dimethylethylenediaminomethyl-bis-phosphonic acid (MDEDAP). MDF specimens were painted three times with 15 wt% solution of the alkylenediaminoalkyl-bis-phosphonic acids at room temperature. After drying specimen treated with chemicals, combustive properties were examined using the cone calorimeter (ISO 5660-1). As a result, combustion-retardation properties increased due to the treatment of bare MDF with alkylenediaminoalkyl-bis-phosphonic acid solution. Especially, the specimens treated with chemicals showed the ignition (TTI) (148 s~116 s) was retarded and the flameout (Tf) (633 s~529 s) time increased, while the total heat release rate (THRR) (61.1~67.0) <TEX>$MJ/m^2$</TEX> was lowered than those of using virgin plate by reducing the burnig rate. Compared with virgin MDF plate, the specimens treated with the alkylenediaminoalkyl-bis-phosphonic acids showed low combustive properties. However the specimens treated with bis-(dimethylaminomethyl) phosphinic acid (DMDP) showed the higher peak heat release rate (PHRR) (<TEX>$185.08kW/m^2$</TEX>) than that of the virgin plate.

알킬렌디아미노알킬-비스-포스폰산 유도체에 의해 처리된 중밀도섬유판의 연소성

이 연구에서는 피페라지노메틸-비스-포스폰산(PIPEABP), 메틸피페라지노메틸-비스-포스폰산(MPIPEABP), N,N-디메틸 렌디아미노메틸-비스-포스폰산(MDEDAP), 비스-디알킬아미노알킬 포스폰산(DMDAP)으로 처리된 중밀도섬유판(MDF)의 연소성을 시험하였다. 15 wt%의 알킬렌디아미노알킬-비스-포스폰산 수용액으로 MDF에 3회 붓칠하여 실온에서 건조시킨 후, 콘칼로리미터(ISO 5660-1)를 이용하여 그의 연소성을 시험하였다. 그 결과, 알킬렌디아미노알킬-비스-포스폰산 및 비스-디메틸아미노메틸 포스피닉산(DMDAP)로 처리한 시험편은 연소속도 감소에 의하여 무처리한 시험편에 비해 최대질량감소율 도달시간(<TEX>$TMLR_{peak}$</TEX>) = (340475) s을 지연시켰다. 게다가 <TEX>$CO_{mean}$</TEX>은 (0.0883~0.0963) kg/kg으로서 무처리한 시험편(0.0612 kg/kg)보다 높게 측정되었다. 특별히 화학 첨가제 수용액으로 처리한 시험편의 비소화면적(<TEX>$SEA_{mean}=5m^2/kg{\sim}21.5m^2/kg$</TEX>)은 무처리한 시험편의 비소화면적(<TEX>$-426.8m^2/kg$</TEX>) 보다 높았다. 따라서 알킬렌디아미노알킬-비스-포스폰산 및 비스-디알킬아미노알킬 포스폰산으로 처리된 MDF의 시험편은 무처리한 MDF 시험편의 난연성을 향상시킨 것으로 판단된다. 그러나 연기발생량 감소에는 부정적인 영향을 주었다. This study was performed to test the combustive properties of Medium Density Fibreboard (MDF) specimens treated with piperazinomethyl-bis-phosphonic acid (PIPEABP), methylpiperazinomethyl-bis-phosphonic acid (MPIPEABP), and N,N-dimethylethylenediaminomethyl-bis-phosphonic acid (MDEDAP). MDF Plates were painted in three times with 15 wt% solution of the alkylenediaminoalkyl-bis-phosphonic acids at the room temperature, respectively. After drying specimen treated with chemicals, combustive properties were examined by the cone calorimeter (ISO 5660-1). It was indicated that the specimens treated with chemicals showed the later time to peak mass loss rate (<TEX>$TMLR_{peak}$</TEX>) = (340475) s than that of virgin plate by reducing the burning rate. In adition, the specimens treated with chemicals showed the higher <TEX>$CO_{mean}$</TEX> production (0.0883~0.0963) kg/kg than that of virgin plate. Especially, the specimens treated with chemicals showed the higher mean smoke extinction area (<TEX>$SEA_{mean}$</TEX>) (<TEX>$5m^2/kg{\sim}21.5m^2/kg$</TEX>) than that of virgin plate. Thus, It is supposed that the combustion-retardation properties were improved by the partial due to the treated alkylenediaminoalkyl-bis-phosphonic acids in the virgin MDF Plate. However, It gave a negative effect on smoke reduction.

Effect of resin content and pressure on the performance properties of rubberwood-kenaf composite Board Panel

The possibility of manufacturing rubberwood and kenaf (Hibiscus cannabinus L.) stem medium density fibreboard (MDF) panels at different pressure and resin content were investigated. The effect of mechanisms of interacted independent variables (resin content and pressure) on MDF properties was analyzed. The board performance was evaluated by measuring internal bond (IB) strength, modulus of rupture (MOR), modulus of elasticity (MOE), water absorption (WA) and thickness swell (TS). The test results were statistically analyzed by using response surface method (RSM) to determine the significant independent variables that influenced MDF properties. A mathematical simulation or response surface models were developed to predict the MDF properties (MOR, MOE, IB, WA and TS). The obtained results showed that MDF density and all interactions between the experimental variables were significant factors that influenced the mechanical properties of MDF. At 8 bar and 14 % resin content, the MDF recorded WA of 83.12 % and TS of 20.2 %. It can be inferred that two parameters (resin content and pressure) had positive effect on physical and mechanical properties of MDF. We concluded that resin content show more significant effects on MDF manufacturing as compared to pressure parameters.

Effects of resin and moisture content on the properties of medium density fibreboards made from kenaf bast fibres

The effects of different factors including resin type, resin content and moisture content on the physicomechanical properties of medium density fibreboard (MDF) panels made from kenaf (Hibiscus cannabinus L.) bast fibres are investigated. The Taguchi method of experimental design is employed to determine the effects of the factors and to find the levels of factors that result in desirable properties. Three different commercial resins namely, urea formaldehyde (UF), phenol formaldehyde (PF) and melamine urea formaldehyde (MUF) are used in the manufacturing of kenaf MDF panels. The panels are produced with a target thickness of 9mm and density of 700kg/m3. The results indicate that resin type and moisture content have significant influence on the mechanical properties while resin content is the least significant. On the other hand, for physical properties resin content and moisture content have much lesser influence as compared to resin type. This initial study reveals that kenaf panels produced with MUF resin at higher resin loading and intermediate level of moisture content, show elevated properties in accordance with wood based MDF standard ANSI A208.2-2009 for Grades 130 and 155.

Effect of Refining Parameters on Medium Density Fibreboard (MDF) Properties from Oil Palm Trunk

The properties of medium density fibreboard (MDF) made from oil palm trunk (OPT) as affected by refining pressure and preheating time were investigated. The OPT chips were refined in the MDF pilot plant by using four refining pressures (2, 4, 6 and 8 bar) and four different preheating time (100, 200, 300 and 400 seconds). The refined fibres were blended with 10% of urea formaldehyde with a board target density of 720 kg/m3. MDF boards were evaluated based on European Standard EN 622-5:2006 for thickness swelling (TS), internal bonding (IB), modulus of rupture (MOR) and modulus of elasticity (MOE). Analysis of variance (ANOVA) was used to analyze the significance of the factors. The results from this study indicated that refining pressure and preheating time are significant factors for all MDF properties. Low refining pressure and preheating time produced higher TS, lower MOR and MOE with poor bonding than those boards prepared from fibres refined at higher refining pressure and longer preheating time. OPT fibre treated with 8 bar produced good swelling resistance but detrimental on mechanical properties of the finish board. 6 bar steam pressure offered the highest value of mechanical properties (MOE, MOR and IB). Boards from intermediate refining condition (6 bar and 300 seconds) were found the better board properties having 14.58%, 0.73 N/mm2, 38 N/mm2 and 3597 N/mm2 for TS, IB, MOR and MOE respectively.

Properties of medium density fibreboard panels made from rubberwood and empty fruit bunches of oil palm biomass

This study presents an evaluation of the physical and mechanical properties of medium density fibreboards produced from mixture of rubberwood from RRIM 2020 clone and empty fruit bunch fibres. The evaluations are conducted to determine variance in density, moisture content, modulus of rupture, modulus of elasticity, internal bonding, thickness swelling and water adsorption for these mixtures. The significance level of p &lt; 0.05 was used to determine the variations between different ratios of rubberwood and empty fruit bunch fibre blends effect on all properties studied. Most properties of medium density fibreboard panel made with 100% rubberwood fibres are significantly better than medium density fibreboard made with 100% empty fruit bunch fibres. Additional of 30% of empty fruit bunch in mixture had decreased modulus of elasticity by 148 MPa, modulus of rupture by 1.21 MPa and water adsorption by 0.05% compared to 100% rubberwood. Generally, among mixtures, panels containing less than 50% oil palm empty fruit bunch in the mixture exhibits better strength properties but lower physical properties. The dimensional stability (thickness swelling) of the panel made from the mixture of 70% rubberwood and 30% empty fruit bunch board displays the best performance among the mixture.

Properties of medium density fibreboard (MDF) from kenaf (Hibiscus cannabinus L.) core as function of refining conditions

The objective of this study was to evaluate physical and mechanical properties of medium density fibreboard (MDF) panels made from kenaf core as function of fibre geometry and refining conditions. Raw material was prepared by using pressure levels of 3, 5 and 7bar at two heating times, namely 3 and 5min. The length and width of the fibres were determined employing image analyser. Experimental samples with a target density of 700kgm−3 were produced with 12% of urea formaldehyde as a binder. Physical properties such as swelling in thickness (TS) and water absorption (WA) of the panels in addition to their mechanical properties including modulus of rupture (MOR), modulus of elasticity (MOE) and internal bonding (IB) were evaluated based on MS 1787:2005. Based on the test results, low digestion pressure produced longer fibre length and panels made from these fibres had higher TS with MOR and MOE than those of the others panels. However, the IB properties of samples were low. Panels made from shorter fibre resulted in contradict properties found above. The ideal properties of the samples were found for the panels made having fibre length of 0.81mm and aspect ratio of 23.4. Such sample had 14.6%, 63.2%, 30.3MPa, 3619MPa and 0.66MPa for TS, WA, MOR, MOE and IB, respectively.

Effects of Preparation Parameters on Properties of Soy Protein-Based Fiberboard

The effects of manufacturing parameters on mechanical properties of medium density fibreboard (MDF) bonded with modified soy protein-based glue were studied to find an appropriate manufacture technology. Physical properties of MDF made with different amount of wax emulsion were measured. Results indicated that water repellent had no obvious influence on physical properties of soy protein-based MDF boards. The fiberboards bonded with soy protein-based glue showed stronger water resistance properties than those bonded with urea–formaldehyde (UF) resins. Furthermore, the soy protein-based MDF boards had good quality [25.2% 24 h soak thickness swell (TS), 29.9 MPa modulus of rupture (MOR), 3130 MPa modulus of elasticity (MOE)], which met requirements of Chinese national standard. Practical processing parameters were obtained by orthogonal experiment, i.e., glue content 8.0%, hot-press temperature 200 °C, and hot-press time 150 s.

Influence of hydrothermal modification of fibers on some physical and mechanical properties of medium density fiberboard (MDF)

Any treatment of fibers can influence properties of medium density fibreboard (MDF). In this research, the effects of hydrothermal treatment on physical and mechanical properties of MDF were studied. Industrial fibers were hydrothermally treated in a stainless steel reactor at 120, 150 and 180 °C for 0, 30 and 90 min as holding time. Test boards were made based on 0.7 g/cm3 target density, with 10 mm thickness under a pressure of 30 bar and at a temperature of 170 °C and a press time of 10 min. The boards were tested for internal bonding (IB), moduli of elasticity (MOE) and rupture (MOR), thickness swelling and water absorption.

Properties of medium-density fibreboard (MDF) based on wheat straw and melamine modified urea formaldehyde (UMF) resin

Wheat straw was investigated as a raw material for manufacturing of medium density fibreboard (MDF) in a fully equipped pilot-plant. Commercial urea melamine formaldehyde (UMF) and a mixture of UMF-resin and urea melamine phenol formaldehyde (UMPF) adhesives were used as binders in manufacturing of high performance MDF. The study evaluated the quality of MDF produced of straw (i.e., SMDF). Different qualities of wheat straw and different resin contents (14–17%) were used. Moreover, the SMDF was produced at different thicknesses of 9 and 16 mm and densities of 750–1000 kg/m 3. The properties of the resulting SMDF were evaluated by analysing mechanical and water absorption (anti-swelling) properties as a function of density. Internal bond (IB), modulus of rupture (MOR), modulus of elasticity (MOE), thickness swelling (TS), and water absorption (WABS) were the properties analysed. SMDF-panels produced with densities above 780 kg/m 3 and resin contents above 14% met the requirements for wood-based MDF standard EN 622-5:1997.