Wood Modification and Wood Preservation
Seyedeh Masoomeh Zamani; Reza Hajihassani; Kamyar Salehi
Abstract
AbstractThe purpose of this study was to evaluate effectiveness of brown rot fungus on ash (Fraxinus Sp.) and spruce (Picea Sp.) thermo-wood and also thermally modification on fungal functionality. In first step, prepared wood samples of both species were heat treated under 212 ºC for 3 hours. Afterwards, ...
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AbstractThe purpose of this study was to evaluate effectiveness of brown rot fungus on ash (Fraxinus Sp.) and spruce (Picea Sp.) thermo-wood and also thermally modification on fungal functionality. In first step, prepared wood samples of both species were heat treated under 212 ºC for 3 hours. Afterwards, heat-treated and untreated wood specimens were exposed to brown rot fungus for 16 weeks based on EN 313 and the functionality of fungal destructive agent and also its effect on physical and mechanical properties were finally analyzed. The obtained results showed that the brown rot fungus has been more efficiency on untreated specimens in compared with thermo-wood in both two wood species and caused more destruction and mass loss. Moreover, the results revealed that some physical and mechanical properties include density, compression parallel to grain and impact strength of exposed heated specimens to brown rot fungus were more than unexposed heated specimens to this fungus. Evaluation of laccase activity which produced by brown rot fungus showed more its effect on controls than heat treated specimens in both wood species. Based on the results, thermally modification can generally causes improvement of biological resistance, reduction of some physical and mechanical properties as well as more stability of applied properties of ash and Picea wood which exposed to the brown rot fungus.
Management and Economics wood
Reza Jazayeri; Reza Hajihassani; Sedighe Nazari
Abstract
The main purpose of this study was to evaluate the effect of hydrothermal treatment with boric acid impregnation on some physical and mechanical characteristics and fire resistance of poplar (Populus nigra) and radiata pine (Pinus radiata) wood. In this study, two times of 60 and 90 minutes with two ...
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The main purpose of this study was to evaluate the effect of hydrothermal treatment with boric acid impregnation on some physical and mechanical characteristics and fire resistance of poplar (Populus nigra) and radiata pine (Pinus radiata) wood. In this study, two times of 60 and 90 minutes with two temperatures of 150○C and 180○C were used for the hydrothermal treatment, and boric acid with concentrations of 1, 3 and 5% dissolved in water used for the impregnation treatment. The measurement of the characteristics, including bending strength, impact resistance, volumetric swilling and fire resistance (weight loss due to fire) were done by ASTM-D143, ASTM-D256, ASTM 4446-2002 and ISO 11925 standards, respectively. About fire resistance, 5% boric acid treatment showed the least weight loss due to burning in the wood of two species. As a result of the hydrothermal treatment alone, the fire resistance was even lower than the control. In this regard, the combination of hydrothermal treatment with boric acid treatment resulted in results close to those of hydrothermal with boric acid treatment. Positive effect of hydrothermal treatment on the improvement of dimensional stability, is considered as one of the results of the present study. The temperature of 180○C with a time of 90 minutes reduced the swelling of poplar and radiata pine by about 36.8 and 42%, respectively. Regarding impact resistance, the effect of hydrothermal treatment on the wood of both species and the effect of boric acid treatment on radiata pine wood were negative. Hydrothermal treatment at a temperature of 180○C and with a time of 90 minutes decreased the impact resistance by 28.2% in the wood of both species, and 5% boric acid treatment caused a 13.3% decrease in this property in radiata pine wood.
Reza Hajihassani; seyedeh masoomeh; Saman Ghahri; Kamyar Salehi
Abstract
AbstractThe purpose of this study was to investigate the effect of heat treatment on bio-durability and some physical and mechanical properties of beech (Fagus Sp.) and pine (Pinus Sp.). Thermo-wood samples were prepared from beech and pine species based on thermo-D process. Heat-treated and untreated ...
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AbstractThe purpose of this study was to investigate the effect of heat treatment on bio-durability and some physical and mechanical properties of beech (Fagus Sp.) and pine (Pinus Sp.). Thermo-wood samples were prepared from beech and pine species based on thermo-D process. Heat-treated and untreated wood specimens were evaluated after exposing to brown rot fungus for 16 weeks. The laccase activity and its effect on mass loss and wood density were investigated. Results showed that deterrence value of heat treatment on mass loss caused by brown rot fungus have been 76.92% and 44.32% in beech and pine wood, respectively. So, laccase activity and its efficiency on mass loss of control specimens was more than heat treated wood. The results also showed that thermally modification at high temperatures reduced wood density. However, it had deterrent effect on decrease of density caused by brown rot fungus activity. Moreover, some mechanical properties including impact strength and compression parallel to grain of wood specimens were measured. The results generally showed that thermal modification improves the bio-durability of both wood species. The results also revealed reduction of mechanical properties due to heat treatment except compression parallel to grain.
Saman Ghahri; Antonio Pizzi; Reza Hajihassani
Abstract
Presently, because of the human health issues related to the formaldehyde gas emission initiated from traditional wood adhesives like urea formaldehyde, the bio-sbased adhesives has shown a good solution for preventing health hazards for human and the environment. To achieve an acceptable approach in ...
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Presently, because of the human health issues related to the formaldehyde gas emission initiated from traditional wood adhesives like urea formaldehyde, the bio-sbased adhesives has shown a good solution for preventing health hazards for human and the environment. To achieve an acceptable approach in wood based composites production, these adhesive need to qualify different standard limitations. This research was conducted to improve the bio-based soy-tannin adhesive for producing plywood with acceptable properties. For this goal, different adhesive formulations were prepared in the laboratory and they were treated at different temperature (40, 60, 80 ºC). Poplar wood plies with 2 mm nominal thickness were used to produce plywood specimens. The results showed the effectiveness of adhesives with heat pre-treatments at different temperature on shear strength (dry and wet) of plywood specimens. The highest shear strength of plywood specimens was achieved for 40 ºC treated adhesive in both dry and wet condition. Based on the results of shear strength test, all manufactured plywood specimens successfully met EN-314-2 standards requirement. Also, the results of delamination test revealed that plywood specimens which prepared by 40 ºC treated adhesive can successfully use for indoor condition, based on ANSI-HPV-1 requirements.
Saman Ghahri; Reza Hajihassani; Kamyar Salehi; Fardad Golbabaei
Abstract
In this study, the mechanical properties of kenaf cement composite were investigated using different amounts of kenaf particles (mixture of kenaf core and bark and kenaf core particles). Kenaf-cement composites were manufactured at different levels (10, 15 and 20%) of different kenaf particles. Also, ...
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In this study, the mechanical properties of kenaf cement composite were investigated using different amounts of kenaf particles (mixture of kenaf core and bark and kenaf core particles). Kenaf-cement composites were manufactured at different levels (10, 15 and 20%) of different kenaf particles. Also, Portland cement and calcium chloride (as cement accelerating additive) were used in this research. Calcium chloride and water were mixed well and then kenaf particles were added to the mixture. At next stage, cement was added to the prepared mixture and all component were mixed well. Prepared mixture was molded to the wooden mold and kenaf cement composites were produced. The results obtained from mechanical evaluation of kenaf-cement composites showed the highest bending strength in 10% kenaf bark-cement composites. Also results revealed that highest modulus of elasticity of 10% kenaf core-cement products were obtained. The results of this research revealed the potential of kenaf particles as reinforcement in cement composite production.
Reza Hajihassani; Mohammad Sadeghipour ranjbar; Saman Ghahri
Abstract
The aim of current research was to investigate physical and mechanical properties of particle board made from pistachio lignocellulosic residue. The raw materials were prepared from Sirjan (Kerman province). Sample boards were made from pistachio lignocellulosic residue at two press time (4 and 5 minutes), ...
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The aim of current research was to investigate physical and mechanical properties of particle board made from pistachio lignocellulosic residue. The raw materials were prepared from Sirjan (Kerman province). Sample boards were made from pistachio lignocellulosic residue at two press time (4 and 5 minutes), two press temperature (170 and 180ᴼc) and three compositions (100 percent, 90:10 and 80:20 pruning residue to pistachio shell). The specimens were physically and mechanically tested as water absorption, thickness swelling, bending strength, modulus of elasticity and internal bonding. Afterward, the results were analyzed based on a complete randomized design (CRD) under a factorial experiment. Results revealed that pruning residues of pistachio trees can be used as suitable raw materials for particle board production. Moreover, pistachio shell can be used up to 10 percent in raw material composition, but physical and mechanical properties of boards will be reduced in higher consumption quantities.Keywords: Particle board, pruning residue, pistachio shell, composition, physical and mechanical properties
Reza Hajihassani
Abstract
The aim of current research was to investigate the effect of hydro thermo-mechanical treatment and also press conditions on the physical and mechanical properties of poplar wood (Populus deltoides). The wood blocks were initially treated hydrothermally at temperatures of 100°C for holding time of ...
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The aim of current research was to investigate the effect of hydro thermo-mechanical treatment and also press conditions on the physical and mechanical properties of poplar wood (Populus deltoides). The wood blocks were initially treated hydrothermally at temperatures of 100°C for holding time of 0, 60, 120 minutes. Afterwards, the densification process was carried out under a hot press at two phases 1- contact and 2- compression press, for temperature of 160, 180 and 200°C for 60 and 90 minutes. The wood compression set was adjusted for 40 percent based on the thickness (radial direction) of the blocks. The samples were physically and mechanically tested as density, springback after press, water absorption, thickness swelling, bending strength and modulus of elasticity. Afterward, the results were analyzed based on a complete randomized design (CRD) under a factorial experiment. Results revealed that physical and mechanical properties of samples were enhanced due to the combined hydro thermo-mechanical treatment. Results revealed that this process causes reduction of springback, water absorption and thickness (radial direction) swelling and also improvement of mechanical properties such as bending strength and modulus of elasticity.
Reza Hajihassani; Saman Ghahri; Kamyar Salehi; Fardad Golbabaei; seyedeh masoomeh
Abstract
Abstract In the current research, surface properties and failure modes of modified poplar wood (Populus deltoides) by hygrothermal treatment were evaluated. For this aim, the effect of variable factors included hygrothermal temperature (three levels: 130, 150 and 170°C) and holding time (two levels: ...
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Abstract In the current research, surface properties and failure modes of modified poplar wood (Populus deltoides) by hygrothermal treatment were evaluated. For this aim, the effect of variable factors included hygrothermal temperature (three levels: 130, 150 and 170°C) and holding time (two levels: 20 and 40 minutes) on poplar wood specimens properties (contact angle and surface roughness) prior to and after planning were investigated. The surface characteristics and failure modes were evaluated for both treated and untreated wood specimens. The results revealed that surface roughness of poplar wood was enhanced due to the hygrothermal treatment in both states of before and after planning. It was also found that the hygrothermal treatment decreased contact angle of distilled water. The bending strength of specimens was reduced by hygrothermal treatment. According to the results, failure modes of hygrothermally treated specimens were simple and compression types in bending strength test. Keywords: Surface roughness, contact angle, bending strength, failure mode
Amir Nourbakhsh; Abolfazl Kargarfard; Reza Hajihassani; Saman Ghahri; Fardad Golbabaei
Abstract
In this study, the resistance properties of nanocomposite plastic wood produced using 5 levels of cellulosic wastes (bagasse, corn stalk, rice stalk, sunflower stem and canola stem), three levels of nanomaterials (carbon nanotubes, nano silica, nanoclay) ) And urban polymer wastes (PP polypropylene and ...
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In this study, the resistance properties of nanocomposite plastic wood produced using 5 levels of cellulosic wastes (bagasse, corn stalk, rice stalk, sunflower stem and canola stem), three levels of nanomaterials (carbon nanotubes, nano silica, nanoclay) ) And urban polymer wastes (PP polypropylene and HDPE heavy polyethylene, etc.) were investigated. In order to chemically bind the wood / polymer fiber composites, chemicals and reinforcers (pairing agents) have been used due to the hydrophilic properties of cellulose fibers and plastic drainage. Extruders and hot presses were used to study the mechanical properties and bonding of composites. The results showed that the use of HDPE heavy polymer wastes increased tensile strength, flexural modulus and impact resistance to polypropylene wastes. Regarding the use of agricultural wastes and wastes in the construction of wood-plastic composites, in general, the results have shown that the addition of agricultural waste wastes in several types of plastic wood has significantly improved the bending and tensile properties. Among them, the bagasse stem has a significant advantage over other lignosullose materials. The use of polymer waste and agricultural waste using nano-silica has shown the best results of resistances. In general, the results have shown that the use of agricultural fiber wastes as reinforcers in plastic wood polymers have the expected mechanical properties.
Fardad Golbabaei; Reza Hajihassani; Kamyar Salehi; Asghar Tabei
Abstract
The aim of this study was to construct lightweight structures and reduce energy loss. The aim of this study was to produce cement wood or composite products by combining organic particles such as wood fibers and lignocellulosic materials with monolith. The investigated product consisted of cement wood ...
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The aim of this study was to construct lightweight structures and reduce energy loss. The aim of this study was to produce cement wood or composite products by combining organic particles such as wood fibers and lignocellulosic materials with monolith. The investigated product consisted of cement wood made from scrap wood fibers and poplar wood particle thickness of 20 mm on both sides of the structure and 10 mm thick unolith in the middle of the structure. Products manufactured by Unolite Cement will have a combination of cement and Unolite properties. In this study, according to the studied variables including lignocellulosic materials and amount of additive (such as calcium chloride (Cacl) at two levels of 3 and 5%, the best specimens were prepared using 10% lignocellulosic materials. The thickness of the specimens was uniform at the two monolithic surfaces and all fabrication conditions such as discharge rate, press pressure, coalescence rate were assumed to be uniform and constant.In static bending experiment the mean maximum load force for ordinary brick failure was 3933.26N and the mean. The maximum load for breaking the cement stick was 389/78 N, which was approximately It has 10% resistance to ordinary brick but ordinary brick breaks abruptly when fractured, while the monolithic brick is gradually broken and the insulation properties due to the cellulosic fibers and the monolith in it are higher than the ordinary brick due to its low resistance to use. Recommended in partitions.
Composite wood products
Reza Hajihassani; Fardad Golbabaei; seyedeh masoomeh
Abstract
The aim of current research was to investigate effect of chemical treatment of poplar fibers on physical and mechanical properties of wood plastic composite. The samples were made from acetylated poplar fibers with different weight percent gains (WPGs of 0, 14.7 and 19.5%), two levels of fiber consumption ...
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The aim of current research was to investigate effect of chemical treatment of poplar fibers on physical and mechanical properties of wood plastic composite. The samples were made from acetylated poplar fibers with different weight percent gains (WPGs of 0, 14.7 and 19.5%), two levels of fiber consumption (30 and 40%) as well as two levels of MAPP (0 and 3%). The samples were physically and mechanically tested. Afterward, the results were analyzed based on a complete randomized design (CRD) under a factorial experiment. Results revealed that the acetylation causes reduction of water absorption and thickness swelling and also improvement of some mechanical properties. Moreover, the results showed that the utilization of MAPP increases physical and mechanical properties of wood plastic composite. The research results showed that increasing of fiber consumption from 30 to 40% enhances water absorption, thickness swelling, tensile strength, tensile modulus as well as bending modulus, and also causes reduction of bending strength and impact resistance.
Abolfazl Kargarfard; Reza Haji hassani
Abstract
The aim of this investigation was concentrated on the possibilty of untilizing corn cops residues in the production of particleboard. Two press temperatures of 170 and 180 oC, and four ratios of corn cop/poplar wood particles (100/0, 75/25, 50/50 and 25/75) in the corn layer of the boards and 100% poplar ...
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The aim of this investigation was concentrated on the possibilty of untilizing corn cops residues in the production of particleboard. Two press temperatures of 170 and 180 oC, and four ratios of corn cop/poplar wood particles (100/0, 75/25, 50/50 and 25/75) in the corn layer of the boards and 100% poplar wood particles in the surface layer were used. A combination of 16 treatments were reached and three laboratory boards for each treatment were made. Physical and mechanical properties of the boards were measured and statistically analyzed. The grouping of the averages were based on duncan multiple range test. The results indicated that the influence of the press temperature on both modulus of rupture and modulus of elasticity was statistically significante and boards produced applying 170 oC reached higher values. As the ratio of the corn cop particles in the particle mixture in core layer increased, both modulus of rupture and internal bonding deteriorated and the highest value were measured at 50/50 ratio of the particle in the core layer. The Boards which produced applying higher press temperature exhibited hgiher rate of thickness swelling . Lower ratios of the corn cop particle in the mixture of particles in the core layer improved the properties of the boards. So that the ratio of 50/50/ and 25/75 produced lower thickness swelling. The results of this research revealed that eventhough boards produced using corn cop particles did not produce comparable properties to the boards based on poplar particles, but it can be concluded that if 50/50 ratio of particles, press temperature of 170 oC is used for board making, the mechanical properties of the produced boards will meet the requirement of DIN specifications.
Composite wood products
Fardad Golbabaei; Kamyar Salehi; Reza Hajihassani
Abstract
In this study, the composition of bagasse composite was investigated using different amounts of bagasse particles. Bagasse and cement particles are manufactured at levels (5, 10 and 15%) and percentage of calcium chloride as cement accelerating additive at two levels (3 and 2%) based on cement dry weight. ...
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In this study, the composition of bagasse composite was investigated using different amounts of bagasse particles. Bagasse and cement particles are manufactured at levels (5, 10 and 15%) and percentage of calcium chloride as cement accelerating additive at two levels (3 and 2%) based on cement dry weight. Then, the mixture was poured into a mold measuring 15 8 18 8 8 cm and the excess water was removed from the bottom of the mold and initially weighed 10 kg on the specimens. The specimens were removed from the mold after 48 hours and kept in a glass saturated room at 90% humidity for 14 days and then finally dried in a laboratory environment. The bending strength and physical properties tests were performed on the specimens. The results showed that bagasse particles had a significant effect on bending strength and other physical properties. The bending strength was highest in boards made with 10% bagasse particles.
Mechanical conversion of wood and wooden fittings
Fardad Golbabaei; Reza Hajihassani; Kamyar Salehi
Abstract
With full respect for the principles of linking wood and conservation project Eldar pine because having good mechanical properties and availability of a wood structure in the form of pavilions chose alcove to the octagon without internal column with computer software Sketch up of Alborz research center ...
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With full respect for the principles of linking wood and conservation project Eldar pine because having good mechanical properties and availability of a wood structure in the form of pavilions chose alcove to the octagon without internal column with computer software Sketch up of Alborz research center with trees and landscaping of the complex was built. In making these structures all stages of the preparation of the wooden parts of drying are quite principled and dried in the open air during the six months were roof wood structure with the use of Eldar pine just Lambe was made in setting up the ceiling of solar connection on an octagonal timber wood using mortise and tenon mode and auxiliary metal was used. Sliding windows can be made to occupy less space. After completion of the period of three months to review the different pieces in different parts of the structure and measurements of physical densities, shrinkage and swelling and mechanical testing of hardness and impact resistance and protection review different parts of the fungal infection and decay structures was investigated. Since shortly after the beginning of the measure is going to change in the early stages of measuring statistically Darnbvdh but in the last stage of a decrease in density of about 5% and reduce the hardness of about 8% were signs of shrinkage and swelling in various parts of it to be seen.
Composite wood products
Fardad Golbabaei; Amir Nourbakhsh; Abolfazl Kargarfard; Reza Hajihassani
Abstract
In this study, the reinforcing effect of recycled newsprint paper (RNP) in cement boards has been investigated. The experiment was designed to apply two variable factors, RNP and calcium chloride (CaCl2). Cement-fiber boards with the density of 0.7 kg/m3 were manufactured using fiber/cement ratios of ...
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In this study, the reinforcing effect of recycled newsprint paper (RNP) in cement boards has been investigated. The experiment was designed to apply two variable factors, RNP and calcium chloride (CaCl2). Cement-fiber boards with the density of 0.7 kg/m3 were manufactured using fiber/cement ratios of 10:90, 15:85, 20:80 and 25:75 (w/w) and 3% and 5% CaCl2 as accelerator. Minimum four boards (replications) were fabricated for each combination of variables, and the mechanical and physical properties of the boards were evaluated. The statistical analysis showed that the effect of the RNP and CaCl2 contents on modulus of rupture of cement fiber boards were significant at 1% significant level. The results showed that addition of CaCl2 enhanced the mechanical properties of the boards. All properties of the boards were improved as the CaCl2 content was increased from 3% to 5%. The modulus of rupture and modulus of elasticity of the boards decreased with addition of RNP, and the maximum values were obtained at RNP loading of 10%. The results also showed that as the fiber content was increased, significant increase in water absorption and thickness swelling occurred. Increasing RNP fiber content from 10% to 25% reduced both the mechanical and physical properties considerably. The optimum condition was obtained when the RNP and CaCl2 contents were 10% and 5%, respectively.
Management and Economics wood
Reza Hajihassani; Behbood Mohebi; Saeid Kazemi Najafi; Parviz Navi
Abstract
Abstract The present research work has investigated the physical and mechanical properties of hygro-thermally modified poplar (Populus deltoides) wood. The poplar wood blocks were treated hygrothermally at temperatures of 130, 150 and 170°C and for 20, 40 minutes as holding time. The physical and ...
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Abstract The present research work has investigated the physical and mechanical properties of hygro-thermally modified poplar (Populus deltoides) wood. The poplar wood blocks were treated hygrothermally at temperatures of 130, 150 and 170°C and for 20, 40 minutes as holding time. The physical and mechanical properties were determined for both treated and untreated wood. The properties; mass loss, collapse, specific gravity changes, dimensional stability, surface roughness, bending strength and modulus of elasticity, were determined prior to and after the treatment in all wood blocks. As expected, the hygrothermal treatment significantly improved the dimensional stability of the samples. It was also found that the hygrothermal treatment could increase collapse, surface roughness and modulus of elasticity due to the treatment. However, there were decreases in wood mass, specific gravity and bending strength of the treated poplar wood. It was revealed that the mass loss, decrease in the density as well as collapse in woos is correlated with treatment temperature as well as the holding time. While, raise of the treatment temperature as the holding time caused increase of the dimensional stability.
Management and Economics wood
Reza Hajihassani; seyedeh masoomeh
Abstract
Abstract In this research, the effects of acetylation on the prevention of white-rot and brown-rot fungi deterioration in medium density fiberboard (MDF) were investigated. Sample boards were made from acetylated poplar fibers, which were treated at different times (0, 30, 90 and 270 minutes) to obtain ...
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Abstract In this research, the effects of acetylation on the prevention of white-rot and brown-rot fungi deterioration in medium density fiberboard (MDF) were investigated. Sample boards were made from acetylated poplar fibers, which were treated at different times (0, 30, 90 and 270 minutes) to obtain different weight percent gains (WPGs of 0, 4.85, 9.1, and 15.8 %). Totally twelve samples boards at three replication for every treatment were made.. The results were analyzed based on a complete randomized design (CRD) under a factorial experiment. Results revealed that the acetylation decreased the deterioration effect of white-rot and brown-rot fungi. As it was determined, the weight reduction of acetylated boards with the highest WPG (15.8 %) after 16 weeks were measured as 1.605 % and 16.93 % for white and brown-rot fungi, respectively. It was also determined that the weight loss of the control (untreated boards) samples was measured as 39.96 and 49.31% in the same period. The research results showed that the acetylation enhances biologic resistance in medium density fiberboard.
Composite wood products
Amir Nourbakhsh; Reza Hajihassani; Fardad Golbabaei; Moghgan Kohpayeh zadeh
Abstract
Wood fibers are increasingly being used as reinforcement in commercial thermoplastic composites due to their low cost, high specific strength properties and renewable nature. The ultimate goal of our research was to find the fundamental understanding of the mechanical behavior of poplar wood fiber/polypropylene ...
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Wood fibers are increasingly being used as reinforcement in commercial thermoplastic composites due to their low cost, high specific strength properties and renewable nature. The ultimate goal of our research was to find the fundamental understanding of the mechanical behavior of poplar wood fiber/polypropylene (PP) composites. The effect of wood fiber concentrations and compounding temperature on the mechanical properties of composites, prepared using MAPP as the coupling agent, was investigated. In the sample preparation, four levels of fiber loading (10, 20, 30, and 40 w/w%) and three compounding temperatures (180, 190, and 200oC) were used. The results revealed that the major changes in composite properties occurred at fiber contents above 30%. The results clearly showed that the fiber loading of 30 and 40 w/w% at 190oC provided adequate reinforcement to increase the tensile and flexural strength of the composite. The modulus also increased with increasing fiber content, because poplar wood fibers are believed to be more rigid than polymer. However, the addition of wood fibers resulted in the reduction of both elongation and impact strength properties of the composites. The FTIR spectroscopy showed that the polymer was bonded to the fibers by ester linkages and hydrogen bonds at 1705–1735 cm-1.
Reza Hajihassani; Hossein Hosseinkhani; Abolfazl Kargarfard; Fardad Golbabaei
Abstract
The impact of reeds residue addition on physical and mechanical properties of particleboard made from pomegranate pruning was investigated. Laboratory particleboard was made applying one of the three levels of press time (3, 4 and 5 minutes) and one of the four levels of reed ...
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The impact of reeds residue addition on physical and mechanical properties of particleboard made from pomegranate pruning was investigated. Laboratory particleboard was made applying one of the three levels of press time (3, 4 and 5 minutes) and one of the four levels of reed and pomegranate pruning mixture (1-100% reeds; 2- 75% reeds + 25% pomegranate pruning; 3- 50% reeds + 50% pomegranate pruning and 4- 25% reeds + 75% pomegranate pruning). Boards were made in three replicate and 36 boards were made. Boards were tested using relevant EN standard and results were analyzed based on complete randomized design (CRD) under factorial experiment. Results revealed that increasing of pomegranate pruning in the wood mixture imposed positive effect on MOR, MOE, IB and thickness swelling of the particleboard. The relevant values of MOR, and MOE of the boards produced using 25% reeds + 75% pomegranate pruning were determined as 16.20 MPa and 2533 MPa respectively. Also thickness swelling after for 2 and 24 hours soaking in water decreased from 17.51 and 33.21% to 9.33 and 16.84% respectively. Internal bond strength (IB) of boards made applying 3 minutes press time (0.17 MPa.) was higher than boards made pressed for either 4 or 5 minutes, which indicates that 3 minutes press time is the appropriate time to approach maximum MOR and minimum thickness swelling after 24 hours soaking in water.
Fardad Golbabaei; Hossein Hosseinkhani; Abolfazl Kargarfard; Amir Nourbakhsh; Reza Hajihassani
Abstract
The major engineering properties of Pinus taeda L. wood growing in different regions of Caspian forests (North of Iran) was determined. Test materials were selected randomly from Pinus teada tree plantation and the test specimens were prepared according to ASTM D-143 standard. Mechanical and physical ...
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The major engineering properties of Pinus taeda L. wood growing in different regions of Caspian forests (North of Iran) was determined. Test materials were selected randomly from Pinus teada tree plantation and the test specimens were prepared according to ASTM D-143 standard. Mechanical and physical properties were measured on both green and air-dried samples (12% moisture content). The results of the measurement were statistically analyzed based on randomized block design and factorial experiment. The influence of specimen locations at different stem heights was examined. Based on the results of this study, statistically significant difference of the measured properties was not observed between the samples collected from different regions. Toughness was not influenced by moisture content, but the compression strength perpendicular to the grain of wet and air-dry specimens was not similar. Mechanical properties of Pinus teada wood grown in Iran is generally of lower quality compare to those in their original habitat.
Composite wood products
Abolfazl Kargarfard; Reza Hajihassani; Fatemeh Rezaei
Abstract
In this investigation, 36 laboratory Medium Density Fiberboard (MDF) panels were produced using beech wood fibers. Variables were three steaming time (5, 10 and 15 minutes), two press time (4 and 6 minutes) and two resin consumption levels (9 and 11%). The physical and mechanical properties of panels ...
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In this investigation, 36 laboratory Medium Density Fiberboard (MDF) panels were produced using beech wood fibers. Variables were three steaming time (5, 10 and 15 minutes), two press time (4 and 6 minutes) and two resin consumption levels (9 and 11%). The physical and mechanical properties of panels were measured and analyzed. The results indicated that the favorite MOR was observed in panels produced through 4 minutes press time, 11% resin consumption and 10 minutes steaming time. Also increase in steaming time to 15 minutes and press time to 6 minutes, caused the MOR and MOE of boards reduced to minimum level. The internal bonding (IB) of boards decreased with steaming and press time increase. However, the panels produced at 25 minutes of steaming time showed minimum of thickness swelling. The results of this investigation indicated that the thickness swelling of boards improved with increase in steaming time. However mechanical properties of boards were higher where the shorter steaming time applied.
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 ...
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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.
Composite wood products
Abolfazl Kargarfard; Amir Nourbakhsh; Reza Hajihassani
Abstract
In this investigation, the influence of press temperature and press time on MDF properties made from Eucalyptus wood (Eucalyptus intertexta sp.) have been studied. Variable factors were steaming time (in two levels: 5 and 10 minutes), press temprature (in two levels: 180 and 190 °C ) and press time ...
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In this investigation, the influence of press temperature and press time on MDF properties made from Eucalyptus wood (Eucalyptus intertexta sp.) have been studied. Variable factors were steaming time (in two levels: 5 and 10 minutes), press temprature (in two levels: 180 and 190 °C ) and press time (in three levels: 3, 3.5 and 4 minutes).
The results of this study indicated that the effect of steaming time on MOR had been significant, the highest MOR were obtained 14.62 Mpa in MDF boards that produced in 5 minutes steaming time. Also the MOR of boards were increased with ascending of press temperature. The results also showed that the effect of press temperature on MOE had been significant and MOE of boards were increased with ascending of press temperature.
The results revealed that increasing of steaming time and press time had been negative effect on IB. on the other hand press time had a significant effect on thickness swelling as the minimom of thickness swelling had obtained in 3 minutes press time.
Composite wood products
Amir Nourbakhsh; Kazem Dosthosseini; Abolfazl Kargarfard; Fardad Golbabaei; Reza Hajihassani
Abstract
This study investigated the effects of production variables on physical and strength properties of air-formed OCC fibers / polymer composites. A combination of 12 treatments of OCC fibers and coupling agents for air-forming were investigated. Physical and mechanical properties of the sample were ...
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This study investigated the effects of production variables on physical and strength properties of air-formed OCC fibers / polymer composites. A combination of 12 treatments of OCC fibers and coupling agents for air-forming were investigated. Physical and mechanical properties of the sample were analyzed using factorial experimental design with completely randomized and DMRT test is used to classified the averages. The results of this study showed that addition of 70% OCC fibers to the polymers in air forming resulted in composites with higher strengths and modulus of rupture and 55% OCC fibers increased internal bonding, tensile strength and modulus, and lowered thickness swelling. Thickness swelling after 2 h water-soak and mechanical properties were improved by addition 2 and 4 % coupling agent
Pulp and paper
Hamid Noori chaparprdy; Ali Ghasemian; Ali Shalbafan; Reza Hajihassani
Abstract
This study has been performed in order to determination of optimum refining of paper made of recovered Kraft liner. Recovered Kraft liner has been prepared from anzali city. After shredding into 5 centimeter pieces, the papers were soaked in distillated water in pail. After 7 days fibers was separated ...
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This study has been performed in order to determination of optimum refining of paper made of recovered Kraft liner. Recovered Kraft liner has been prepared from anzali city. After shredding into 5 centimeter pieces, the papers were soaked in distillated water in pail. After 7 days fibers was separated of each other by disintegrator and freeness for each pulp before and after refining were measured. They were refined in revolutions of 3000, 6000, 9000, 12000 by PFI mill. Hand sheets were made from each revolution in order to TAPPI standard T 205om-95 number, and then were compared with control sample. Analysis of variance of waste papers were conducted using completely randomized design, then mean values were compared, using Duncan’s test, and finally the normalization equations were used to determine the best sample. Results showed that increasing of refining revolution increased strength of burst, tensile and brightness but decrease freeness, thickness and tear strength at product. Normalization equations showed that the best papers made from refining revolution of 9000.
