Ali Hasanpoor tichi; Fardad Golbabaei; Mojtaba Rezanezhad
Abstract
In this study, the possibility of making gypsum-based boards from rice straw chips with different levels was investigated. Variable factors in this study were considered in nano at three levels of 0, 3 and 7% and also the ratio of mixing rice straw to gypsum at three levels ( 5:95 , 10:90 , 15: 85 %). ...
Read More
In this study, the possibility of making gypsum-based boards from rice straw chips with different levels was investigated. Variable factors in this study were considered in nano at three levels of 0, 3 and 7% and also the ratio of mixing rice straw to gypsum at three levels ( 5:95 , 10:90 , 15: 85 %). Thus, with the consideration of nine treatments, a total of 27 laboratory boards were constructed. The specific mass of the first target 1.10 gr/cm3 was considered. Mechanical and physical properties of composites include modulus of rupture, modulus of elasticity, internal bonding, water absorption after 2 and 24 hours of immersion, and density of boards according to standard (DIN-EN-634) and fire resistance (weight loss percentage) they were measured according to a standard ISO-11925. In order to investigate the common chapter of rice straw and gypsum as well as the distribution of nano-wollastonite, microscopic images (SEM) of the fracture surface of the samples were prepared and the results showed that the composites made with nano-wollastonite had higher mechanical and physical strengths. Microscopic imaging (SEM) showed that the boards made with 7% nano had stronger internal connections and created a uniform structure. In this study, composites made of 7% nano wollastonite with 5% rice straw were selected as the optimal treatment.
Management and Economics wood
Foroogh Dastoorian; Faezeh Farhadi; Fahimeh Hoseinzadeh; majid zabihzadeh
Abstract
The present study was done with the aim of investigation of the effect of heat treatment on chemical and physical properties of Iranian beech and Velvet maple. Results of spectroscopy showed that heat treatment led to decrease of hydroxyl groups which became more sensible with increasing temperature ...
Read More
The present study was done with the aim of investigation of the effect of heat treatment on chemical and physical properties of Iranian beech and Velvet maple. Results of spectroscopy showed that heat treatment led to decrease of hydroxyl groups which became more sensible with increasing temperature up to 175oC. Treatment at 190oC led to an increase of hydroxyl group comparing to the control ones. Increasing cellulose crystallinity, decreasing the hemicellulose content, increasing the lignin ratio, degradation of syringyl lignin and increase the condensation reaction of lignin was also obtained from spectroscopy. Results of water absorption tests also showed that heat treatment caused decreasing of water absorption. The water repellent and anti-swelling efficiency for both species showed that heat treatment at 160oC didn’t improve the water repellency and dimensional stability however treatment at 190oC led to decrease of water absorbance specially in beech. In total, the effect of heat treatment on anti-swelling efficiency in beech was more considerable comparing to acer, which can be explained by higher weight loss after heat treatment.
Management and Economics wood
Mohammad Hadi Rezvani; Aisona Talaei; Hosseinali Rajabi Cham Heidari
Abstract
One of the main strategies to develop the extent of wood modification is using active functional groups in wood structure or the so-called impregnation with modified N-methylol compound. The aim of this study was to evaluate the physical properties of paulownia wood after modify with Polycrease ECR Cell ...
Read More
One of the main strategies to develop the extent of wood modification is using active functional groups in wood structure or the so-called impregnation with modified N-methylol compound. The aim of this study was to evaluate the physical properties of paulownia wood after modify with Polycrease ECR Cell wall resin, to name modified dimethylol-dihydroxyethyleneurea (mDMDHEU). Physical test samples were prepared according to ASTM and EN standard and treated with pressure vessel method at two concentration levels; 15 and 25 percent of soluble resin. For polymerization, treated samples were heated in oven for 24-hour periods at 145 and 155 ºC respectively. Weight percent gain (WPG), bulking, water soaking, swelling, anti-swelling efficiency (ASE), leaching and contact angle were determined. High mDMDHEU concentration increased the weight gain and cell wall bulking. Highest weight percent gain (10.70%) and bulking efficiency (6.85%) in to levels of 25% were determined at 155 ˚C. In comparison with the unmodified wood, the mDMDHEU modified wood due to absorbed polymer enhancement exhibited improved dimensional stability and reduced water uptake, and maximum dimensional stability were determined in samples modified using to level 25% mDMDHEU containing solutions and curing temperature 155 ºC. Moreover, mDMDHEU treatment was resistant to leaching. Contact angle measurement further confirmed the improved hydrophobicity of wood after modification. Modification with mDMDHEU improved significantly the physical properties. The improve of the resistance of chemically modified wood exposed to can be attributed to the reduction of wood moisture, bulking of cell walls and cell cavities blocking affect to dominant reactivity mDMDHEU with cell wall wood polymer.
Composite wood products
Samira Brzali; Laya Jamalirad; Farshid Faraji; Sahab Hejazi
Abstract
In this research with the aim of using a natural component, renewable and environmentally friendly which is not environmental pollution, the physical and mechanical properties of plywood manufactured by populous with urea formaldehyde resin and silk cocoon were studied. For this purpose, silk cocoon ...
Read More
In this research with the aim of using a natural component, renewable and environmentally friendly which is not environmental pollution, the physical and mechanical properties of plywood manufactured by populous with urea formaldehyde resin and silk cocoon were studied. For this purpose, silk cocoon was used as filler and reinforcement for four levels of 0, 10, 20 and 30 percent according to dry weight of urea formaldehyde resin. The physical and mechanical properties of samples including water absorption and thickness swelling after 2 and 24 hours immersion in water, bending strength parallel and perpendicular to the surface layer grain and shear strength were measured. The results show that increasing the amount of silk cocoon, decreased water absorption and thickness swelling after 2 and 24 hours immersion in water and increased bending strength parallel and perpendicular to the surface layer grain and shear strength. So that, using 30 percent of silk cocoon, dimensional stability, bending strength and shear strength, were improved.
Mechanical conversion of wood and wooden fittings
Mostafa Poozesh; Hamid Reza Mansouri; babak Nosrati; Alireza Samzadeh
Abstract
This objective of this investigation was to modify and improve the water resistance of urea formaldehyde (UF) bonded particleboard adding Boric acid to the resin. Four levels (1, 2, 3 and 4) of boric acid based on the dry weight of the bonder were added to the UF resin. Then these mixtures were ...
Read More
This objective of this investigation was to modify and improve the water resistance of urea formaldehyde (UF) bonded particleboard adding Boric acid to the resin. Four levels (1, 2, 3 and 4) of boric acid based on the dry weight of the bonder were added to the UF resin. Then these mixtures were used to produce particleboard. Physical and mechanical properties were examined according to the ASTM, D1013-04. The results showed that the using of this additive increased the water absorption and thickness swelling resistance after 2 and 24 hours immersion in water. Also using this additive increased the internal bonding of the boards after 24 hours after immersion in water, compared to the control sample but in the case of dry samples, the internal bonding decreased compared to the control sample. However it was not lower than standard value. As the Boric acid levels increased to 2 percent, bending strength of the samples was increased compare to the control sample and after this level it was decreased. Also with increasing the levels to 4 percent, modulus of elasticity of boards were increased compare to the control sample
Composite wood products
Amineh Behzadi Shahrebabak; Mehrab Madhoushi; Mohammad reza MastriFarahani
Abstract
In this study, the effect of nanoclay and coupling agent on decay resistance and physical properties (including water absorption and thickness swelling) of nanoclay- Polyethylene- MDF sanding- powder composite were investigated. For this aim, MDF sanding dust and polyethylene were used as lignocellulose ...
Read More
In this study, the effect of nanoclay and coupling agent on decay resistance and physical properties (including water absorption and thickness swelling) of nanoclay- Polyethylene- MDF sanding- powder composite were investigated. For this aim, MDF sanding dust and polyethylene were used as lignocellulose and thermoplastic material respectively. Also, Maleic anhydride grafted polyethylene (MAPE) was used in different weight percentages; 3% and 6% as a compatibilizer and nanoclay .Cloisite®15A was used in different weight percentages 2%, 4% and 6%.At first, raw materials were producted to fabricate granules by using twin-screw extruder. Then 36 panels (12 treatments by 3 repetitions) were made by hot pressing with 1 g/cm3 nominal density at dimensions by 30 cm × 28 cm × 1 cm. Then, water absorption and thickness swelling and decay resistant (loss weight) were investigated. Specimens were exposed to Trametes versicolor for 3 months, according to ASTM-D1413 standard. The results shown, water absorption and thickness swelling reduce with increasing MAPE significantly. While, at the time when nanoclay was added 2% (phr), water absorption and thickness swelling reduced significantly and then increased. Also, decay resistance was improved with increasing coupling agent and nanoclay.
taherh Gholipour; Hossein Rangavar; Abolfazl Kargarfard
Abstract
In this study, physical and mechanical properties of wood-plastic composite made of Canola stem flour and polypropylene were investigated. Variable factors were four levels of canola stem flour (25, 50, 75 and 100 percent based on the dry weight of the wood flour) with and without pit. The control samples ...
Read More
In this study, physical and mechanical properties of wood-plastic composite made of Canola stem flour and polypropylene were investigated. Variable factors were four levels of canola stem flour (25, 50, 75 and 100 percent based on the dry weight of the wood flour) with and without pit. The control samples were made of only wood flour and polypropylene. Physical and mechanical properties including screw withdrawal strength perpendicular on the surface, flexural strength, modulus of elasticity, water absorption and thickness swelling after 2 and 24 hours immersion in water were measured in accordance with EN standards. Results showed that increasing the mixing ratio of canola stem flour to wood flour up to 25% resulted in increase in screw withdrawal strength perpendicular to the surface. Increasing this factor up to 50% led to increase in MOR and MOE. Thereafter, any increase in the mixture, decreased mechanical strengths. Increasing the mixing ratio of canola stem flour to wood flour resulted in increase in water absorption and thickness swelling after 2 and 24 hrs. The specimens without pit showed lowest amount of water absorption and thickness swelling levels and highest mechanical properties (screw withdrawal resistance, flexural strength and modulus of elasticity).
Sarveh Hosseinzadeh; Maryam Ghorbani; Porya Biprva
Abstract
This research was conducted to determine the physical properties of poplar wood treated with silica colloidal nanoparticles prepared from rice husk using ash making and alkaline digestion. Test samples were prepared according to ASTM-D1037 standard with the dimension of 2×2×2 cm and then ...
Read More
This research was conducted to determine the physical properties of poplar wood treated with silica colloidal nanoparticles prepared from rice husk using ash making and alkaline digestion. Test samples were prepared according to ASTM-D1037 standard with the dimension of 2×2×2 cm and then were impregnated ina cylinder according to Bethell method applying five concentration levels of soluble colloidal silica nanoparticles (0, 1.2, 1.7, 2.2 and 3.2%). Nanoparticle retention and absorption, density changes, water absorption, and anti-swelling efficiency (ASE) were determined. Nano silica absorption was determined as 119.8, 169.5, 196.3 and 214.7 % corresponding to 1.2, 1.7, 2.2 and 3.2 % nanoparticle addition, respectively. Nano-silica retention in the lowest and the highest treatment level were 1.2 and 9.3%. Results showed that the density increased from 0.37g/cm³ in control samples to 0.40 g/cm³ at the highest level of nano-silica absorption. Water absorption increased by increasing nano-silica absorption. However, dimensional stability of impregnated samples increased. After the longest immersion time, average swelling volume of the sample impregnated with nano-silica was decreased in comparison with the control sample. With increasing nano-silica absorption, anti-swelling efficiency of impregnated samples treated at the 1.2, 1.7, 2.2 and 3.2 % level and immersed for 168h was 36.5, 42.9, 34.7 and 26.8 %, respectively.
Hanieh Ghasemi; Ahmad Jahan Latibari; Abolfazl Karegarfard; Amir Lashgari
Abstract
The impact of the addition of different amounts of canola straw to the composition of the hardwood particles for the production of particleboard was investigated. Four levels (0, 15, 30 and 45%) of Canola particles were added to hardwood particles and then particles were blended with 12% urea resin (based ...
Read More
The impact of the addition of different amounts of canola straw to the composition of the hardwood particles for the production of particleboard was investigated. Four levels (0, 15, 30 and 45%) of Canola particles were added to hardwood particles and then particles were blended with 12% urea resin (based on the oven dry weight of the particles). Boards at three densities of 550, 600 and 650 kg/m3 were produced. The flexural and internal bonding strength and water absorption and thickness swelling after 2 and 24 hours immersion in water of the boards were determined using appropriate EN standard test methods. Addition of different amounts of canola particle to the hardwood particles did not change either modulus of rupture or modulus of elasticity of the boards, but the internal bonding of the boards was reduced. As the dosage of the canola particles increased, both water absorption and thickness swelling were reduced. Increasing the density of the boards increased both strength and dimensional stability.
Azar Haghighi; Hamid reza Taghiyari; Ali nagi Karimi
Abstract
In the present study, fire-retardant properties of nano-wollastonite in fir wood (Abies alba) was studied. Water absorption and volume swelling of the specimens were also measured. Specimens were prepared according to ISO 11925 standard specifications to measure the fire-retarding properties, and ASTM ...
Read More
In the present study, fire-retardant properties of nano-wollastonite in fir wood (Abies alba) was studied. Water absorption and volume swelling of the specimens were also measured. Specimens were prepared according to ISO 11925 standard specifications to measure the fire-retarding properties, and ASTM D4446 -2002 standard to measure physical properties. Impregnation of wood specimens with nano-wollastonite was carried out at four consumption levels of 4, 6/3, 10 and 12%, using Bethel method (full-cell process).Five fire-retarding properties were measured; weight loss (%), ignition point (s), duration of flame after removing the burner (s), duration of glow after removing the burner (s),and carbonization area (%). The results showed that fire-retarding properties increased with the NW-content. Furthermore, the treated wood specimens showed higher dimensional stability.
Ali Pesaraklu; Mohammadreza Dehghani firoz abadi; Abolfazl Karegarfard; Taghi Tabarsa
Abstract
The objective of this study was to manufacture water resistant kenaf stalk particleboard.Twenty seven boards were produced using 170 °C steam treated kenaf particles, 30 and 60minute treatment time and three resin types include urea-formaldehyde, melamineformaldehydeand a mixture of fifty percent ...
Read More
The objective of this study was to manufacture water resistant kenaf stalk particleboard.Twenty seven boards were produced using 170 °C steam treated kenaf particles, 30 and 60minute treatment time and three resin types include urea-formaldehyde, melamineformaldehydeand a mixture of fifty percent each. Physical and mechanical properties weremeasured and the results analyzed in a complete random design plan and by the factorialanalysis. The results showed that boards made from treated particles with 60 minute treatmenttime and Urea Formaldehyde resin had the highest bending strength. Modulus of elasticity(MOE) improved with an increase in treatment time. The greatest MOE was achieved with theboards produced using urea-formaldehyde and the greatest MOE was achieved with the boardsbonded with urea-melamine-formaldehyde resin. Moreover, with increasing treatment time from30 to 60 minutes internal bond strength (IB) reduced. Thickness swelling and water absorptionof the boards was significantly improved with increasing treatment time.
Kazem Dosthosseini; robab ghafari
Abstract
In this research, the effect of increasing content of urea to urea-formaldehyde adhesive on physical and mechanical properties of poplar wood particleboard was investigated. The content of urea added to the adhesive four levels (zero, 4.1, 8.2 and 16 % based on the solid content of adhesive) and ...
Read More
In this research, the effect of increasing content of urea to urea-formaldehyde adhesive on physical and mechanical properties of poplar wood particleboard was investigated. The content of urea added to the adhesive four levels (zero, 4.1, 8.2 and 16 % based on the solid content of adhesive) and two press temperatures of 170 and 180° C as the variable factors were selected. Boards with density of 0.63 gr/cm3 and 10% of the adhesive dosage were made. Mechanical properties including modulus of rupture (MOR), internal bond (IB) and physical properties including water absorption and thickness swelling were measured. Results showed that urea addition to urea formaldehyde adhesive improved the mechanical strengths of the board especially internal bonding reduced the water absorption and thickness swelling. Also, the impact of press temperature on mechanical and physical properties of boards was noticeable and boards produced applying press temperature of 170° C were superior.
Physics and Mechanical Wood
Jafar Eskandari; Amir sohil Pirayeshfar; Mohammad mehdi Jalili; Sayed yahya Mosavi; Mehran Rohnia
Abstract
In this study, three composites (Carbon fiber- Polyester resin, Glass fiber-Polyester resin and Hemp fiber-Polyester resin) are designed as a substitute for the wood in music instruments and their acoustic properties such as elastic modulus, acoustic coefficient, and acoustic coefficient efficiency are ...
Read More
In this study, three composites (Carbon fiber- Polyester resin, Glass fiber-Polyester resin and Hemp fiber-Polyester resin) are designed as a substitute for the wood in music instruments and their acoustic properties such as elastic modulus, acoustic coefficient, and acoustic coefficient efficiency are investigated. For better evaluation of the results, two wood specimens from Cupressus arizonica and Morus Alba trees (which are using in many acoustic applications) were chosen and analyzed as control samples. The results show that the resultant composites possess essential acoustic and vibrational properties so that the result for Carbon fiber-Polyester composite exhibits tremendous acoustic properties than wood samples did. In this paper, the water absorption of resultant composites and wood samples were also measured. The results demonstrate that composites specimens could resist against humidity much better than wood samples.
Pulp and paper
Rabi Behroz; Hamed Unsi kord khelili; Saeid Kazemi najafi
Abstract
Effect of Kraft lignin as a compatibilizer on the short-term water absorption (2 and 24 hours) and mechanical properties of wood flour-polypropylene composites was studied. The black liquor of Chooka pulp and paper mill was acidified and Kraft lignin was extracted by precipitation. The extracted ...
Read More
Effect of Kraft lignin as a compatibilizer on the short-term water absorption (2 and 24 hours) and mechanical properties of wood flour-polypropylene composites was studied. The black liquor of Chooka pulp and paper mill was acidified and Kraft lignin was extracted by precipitation. The extracted lignin at three levels of 2, 5 and 10 percent was mixed with wood flour by physical mixing method. All materials used were oven-dried. Wood flour, lignin and PP with or without MAPP were used to produce composites by flat hot press method. The results of this study indicated that generally lignin improved physical (short term water absorption) and mechanical properties (flexural modulus, flexural strength and impact strength). The bending test result showed that without MAPP, the composites with 2 and 10 percent lignin exhibited higher flexural modulus and strength, respectively. But at the presence of compatibilizer, the composites with 5 percent lignin exhibited the highest flexural modulus and strength. The composite with 2 percent of lignin exhibited higher flexural modulus and short-term water absorption rather than the composites with 2% MAPP. This result indicated positive effect of lignin in the composites. Also the composites with 10 percent lignin exhibited the highest impact strength and short-term water absorption. But there were no significant difference between the impact strength of composites with 5 and 10 percent lignin.
Khodadad Malmir cheghini; Mohammad Talaeipoor; Shademan Pormosa
Abstract
Paper and ink characteristics effect on print density were investigated. For this purpose three types of papers and four types of printing inks at 2 viscosities levels (25-30, 50-55) were used. Then characteristics of paper & ink were measured. Inks on sampled papers Printed and then printing ...
Read More
Paper and ink characteristics effect on print density were investigated. For this purpose three types of papers and four types of printing inks at 2 viscosities levels (25-30, 50-55) were used. Then characteristics of paper & ink were measured. Inks on sampled papers Printed and then printing density was measured. Statistical analysis was conducted based on a complete randomized design in factorial experimental model and means were analyzed and grouped by Duncan multiple range test (DMRT) using SPSS software. Result indicated that Solid content, pH and particles diameter of inks have significant effect on print density. While roughness and water absorption of papers do not have on significantly influences print density. There was not any significant different between two viscosity level and print density
Physics and Mechanical Wood
Morteza Mostafazadeh mrznaki; Saeid kazemi najafi; Majid Chaharmahali; Reza Hajihassani
Abstract
In study, the influence of flour content and immersion time in water on the creep behavior of composites made from mixes PB (Particle Board) and MDF (Medium Density Fiber Board) flour and high density polyethylene (HDPE) waste and was investigated. Mixing was done by a twin screw extruder and the sample ...
Read More
In study, the influence of flour content and immersion time in water on the creep behavior of composites made from mixes PB (Particle Board) and MDF (Medium Density Fiber Board) flour and high density polyethylene (HDPE) waste and was investigated. Mixing was done by a twin screw extruder and the sample was manufactured by flat hot press. Firstly, the modulus of elasticity and bending strength of various mixes PB and MDF flour-polyethylene composites (WPCS) were measured before performing the creep test.It was shown that the modulus of WPCs increases with the increase in mixes PB and MDF flour content from 60% to 70% and then decreases as the flour content reaches to 80%. It is found that the bending strengths of WPCs significantly and linearly decreases with the increase in flour content from 60% to 80%. The results showed that, the creep strain decreases as the lignocellulosic flour level increases. Water absorption has negative effect on creep behavior of mixes PB and MDF flour/HDPE composites. For all filler contents, it can be seen that the creep strain increases when the immersion time increases.
Physics and anatomy
Alireza Ghotibi far; Saeid Kazemi najafi; Rabi Behroz
Abstract
This research focused on the influence of content (5, 10 and 15 %) of glass fiber on the water absorption and thickness swelling of wood flour/E-glass fiber hybrid polypropylene composites without and with MAPP. The samples (strips with 10 mm thickness and 70 mm width) were made using a laboratory twin-screw ...
Read More
This research focused on the influence of content (5, 10 and 15 %) of glass fiber on the water absorption and thickness swelling of wood flour/E-glass fiber hybrid polypropylene composites without and with MAPP. The samples (strips with 10 mm thickness and 70 mm width) were made using a laboratory twin-screw extruder. The water absorption and thickness swelling of the composites after 2h and 24h were determined. The results showed that adding glass fiber significantly increase water absorption and thickness swelling after 2h and 24h in absence of MAPP. Whereas in presence of 2% MAPP by addition glass fiber, no significant changes were observed in water absorption and thickness swelling of the composites after 2h and 24h. MAPP considerably decreased the water absorption and thickness swelling of the studied composites
Pulp and paper
Mohammad Talaeipoor; Habib alah Khademi eslam; Khodadad Malmir chegini
Abstract
Effect of roughness & water absorption of paper and ink characteristics on optical properties was investigated. For this purpose three type of paper and four type of printing ink was used.Then characteristics of paper & ink was measured. Inks on sampled papers Printed and then L, ...
Read More
Effect of roughness & water absorption of paper and ink characteristics on optical properties was investigated. For this purpose three type of paper and four type of printing ink was used.Then characteristics of paper & ink was measured. Inks on sampled papers Printed and then L, a & b was measured. Result indicated that the effect of roughness and water absorption on L, a & b are not significant. But Solid content, PH and particles diameter of four type of ink on L, a & b have significant effect
Aliakbar Ramtin; Behnaz Dadkhahi tehrani; Kazemi Dossthoseini
Abstract
In this study, effects of press temperature and press time on the physical and mechanical properties on the OSB has made from Aspen were investigated. Two levels of press temperature 175ºC and 185ºC and two levels of press time 5 min and 6 min were applied as variables for manufacturing boards. ...
Read More
In this study, effects of press temperature and press time on the physical and mechanical properties on the OSB has made from Aspen were investigated. Two levels of press temperature 175ºC and 185ºC and two levels of press time 5 min and 6 min were applied as variables for manufacturing boards. Mechanical and physical properties such as bending strength, internal bond, water absorption and thickness swelling were measured. results showed that, increase in press temperature and press time causes significant increase on bending strength, internal bond, water absorption and thickness swelling. The best boards were made of press temperature of 185ºC and press time 5 minutes.
Composite wood products
Saeid Kazemi najafi; Ali Shalbafan; Majid Charmahali
Abstract
Density profile of three types of medium density fiberboard (MDF) panels used in Iran market was studied through direct method and gradually removing of layer. Modulus of elasticity, bending strength, internal bond, water absorption and thickness swelling were also determined. The results show that the ...
Read More
Density profile of three types of medium density fiberboard (MDF) panels used in Iran market was studied through direct method and gradually removing of layer. Modulus of elasticity, bending strength, internal bond, water absorption and thickness swelling were also determined. The results show that the shape of density profiles in all types of panels is nearly symmetric and normal, but the profil density in one was deeper, so it showed higher modulus elasticity and bending strength. No significant difference in internal bond was observed between different types of panels.
Composite wood products
asghar tarmian; Kazem Doosthosseini; Seeyed Ahmad Mirshokraie; Mohammadmehdi Faezi poor
Abstract
Beneficial utilization of large quantity of paper sludge from Mazandaran Wood & Paper Industry in particleboard manufacturing has been studied. Single-layer and three-layer particleboard (paper sludge as a surface layer) were produced. Urea-formaldehyde resin at two levels of 10 and 12 percent and ...
Read More
Beneficial utilization of large quantity of paper sludge from Mazandaran Wood & Paper Industry in particleboard manufacturing has been studied. Single-layer and three-layer particleboard (paper sludge as a surface layer) were produced. Urea-formaldehyde resin at two levels of 10 and 12 percent and paper sludge content at 4 levels, 0, 15, 30 and 45 percent were studied. Other factors such as press temperature (160oC), press time (6minutes), mat moisture (12%), board density (0.75g/cm3) and etc were constant factors. Mechanical and physical properties including bending strength, shear strength, thickness swelling and water absorption after 2 and 24 hours immersion were evaluated. The results indicated that application of paper sludge reduced mechanical properties and improved thickness swelling .The particleboard produced with 15%paper sludge had the least water absorption, but by using more paper sludge, water absorption increased. Single-layer particleboard had higher bending strength. However, there was no significant different in shear strength between single and three layer particleboard. Three-layer particleboard showed lower thickness swelling.
