Composite wood products
Morteza Ghanbari; vahid vaziri; farshid faraji; loya jamalirad
Abstract
Background and objective: While wood serves as an excellent renewable building resources, it does have some disadvantages, including its deterioration when exposed to outdoor conditions and its dimensional instability due to fluctuations in relative humidity in the surrounding environment. Heat treatment ...
Read More
Background and objective: While wood serves as an excellent renewable building resources, it does have some disadvantages, including its deterioration when exposed to outdoor conditions and its dimensional instability due to fluctuations in relative humidity in the surrounding environment. Heat treatment can enhance the dimensional stability of panel products, such as particleboard, fiberboard, and OSB. Because during the heat treatment process, numerous chemical transformations take place, including the esterification of hydroxyl groups and the reduction of hemicellulose along with the number of accessible OH groups within the wood. The main objective of this research was to assess the effect of steam pretreatment of garden wood pruning - wood particles on the physical and mechanical properties of particleboard.Materials and methods: Industrial wood particles from Sanate Choube Shomal Company were used. The ratio of wood chips to garden wood pruning was used at level of 70:30. Heat pretreatment was conducted on the wood particles at a temperature of 180 °C with three different retention times (15, 30, and 45 minutes). Urea formaldehyde resin was applied at a 10 percent level based on the dry weight of the raw material as well as ammonium chloride was used as a catalyst at a 2 percent level of the dry weight of the adhesive. After the heat treatment and the mixing processes, the raw materials were formed into a mat at temperature of 160 °C for 5 minutes under a hot press. The physical and mechanical properties were evaluated according to European standards set of EN. The analysis of the Physical and mechanical properties of the panels was performed using variance analysis at a 95% probability level. Results: The results showed that the boards made from treated particles with a 45 minute treatment duration exhibited the highest bending strength, modulus of elasticity, and internal bonding. Since heat treatment softens and ramification of lignin and crystallization of cellulose ratio increases, which improves the strength of the board. . Thickness swelling and water absorption of the boards were significantly improved with increased treatment duration. The main reason for dimensional stability can be attributed reduction of hemicellulose content and hydroxyl groups within the wood component.Conclusion: Based on the finding of this research, heat treatment significantly improved the dimensional stability of the boards. Bending strength, modulus of elasticity, and internal bonding in the treated samples displayed the highest measured values. In comparison to the properties of the boards produced by EN standards, the treated boards at 30 minute and 45 minute duration demonstrated the potential to produce particleboards with desirable attributes suitable for interior fitments board (Type P2) for application in dry conditions.Based on the finding of this research, heat treatment significantly improved the dimensional stability of the boards. Bending strength, modulus of elasticity, and internal bonding in the treated samples displayed the highest measured values. In comparison to the properties of the boards produced by EN standards, the treated boards at 30 minute and 45 minute duration demonstrated the potential to produce particleboards with desirable attributes suitable for interior fitments board (Type P2) for application in dry conditions.
Composite wood products
Haniye Shurvazi; Mohammad Shamsian; Ali Bayatkashkoli; Mohammad Dahmardeh Ghaleno
Abstract
Background and purpose: This study was conducted with the aim of investigating parallel strand lumber (PSL) made from reed waste and laminated veneer lumber (LVL) obtained from poplar wood that reinforced with glass fiber reinforced polymer (FRP) and epoxy resin.Materials and methods: The independent ...
Read More
Background and purpose: This study was conducted with the aim of investigating parallel strand lumber (PSL) made from reed waste and laminated veneer lumber (LVL) obtained from poplar wood that reinforced with glass fiber reinforced polymer (FRP) and epoxy resin.Materials and methods: The independent variable was LVL and PSL with FRP and their comparison control sample without FRP. The mechanical properties of the manufactured boards including bending strength (MOR) and modulus of elasticity (MOE) in the width and edge of the test sample, shear strength, compression strength parallel to the grain, internal bonding and Screw Withdrawal Strengths were investigated as dependent variables. The obtained results were analyzed in the form of completely randomized design by SPSS software.Results: Results showed that of all of the studied mechanical properties, the use of FRP strengthened the PSL and LVL panels. For LVL, the effect of strengthening the samples with FRP was significant at the level of 1% and also for the modulus of rupture of the width and edge samples showed an increase of 93% and 59%, respectively. The value of MOE during reinforcement with FRP showed an increase of 89.6 and 132% for the width and length of the PSL samples, respectively. For LVL, the MOE value of the width and edge of the samples increased by 54 and 95.5% with reinforcement. Reinforced PSL samples have improved their shear strength by 31%, while this value is only 2.5% for LVL. in the internal bonding test, strengthening with FRP improved the internal bonding strength of the samples by 92%. Screw Withdrawal Strengths improved by 27% due to the strengthening of the test samples with FRP.Conclusion: According to the obtained results, it can be stated that the use of glass fibers and epoxy resin has a significant positive effect on the mechanical resistance of PSL made of reed and LVL and it is possible to use low quality raw materials such as reed and waste poplar wood layers.
Composite wood products
Amir Nourbakhsh; Abolfazl Kargarfard; Ali Nourbakhsh; فرداد Golbabaei; Reza Hajihassani; Kamyar Salehi
Abstract
Background and objectives: The possibility of using agricultural lignocellulosic waste as a complementary raw material for the production of wood composite products can have a good economic justification. This will be possible if the manufactured product has the desired and standard quality, however, ...
Read More
Background and objectives: The possibility of using agricultural lignocellulosic waste as a complementary raw material for the production of wood composite products can have a good economic justification. This will be possible if the manufactured product has the desired and standard quality, however, considering that the type of wood material can have a determining effect on the physical and mechanical properties of the final product, therefore, conducting laboratory and research studies in order to recommend A raw material is essential for consumption in industry. The use of agricultural lignocellulosic waste in wood composite products industries has been the subject of various research activities in different parts of the world in recent years. In this research, in order to improve the mechanical and physical properties of wood-plastic, nanoclay particles have been used as reinforcements and corncob wastes have been used with poplar wood.Methodology: The amount of polypropylene and combination of materials were 60 wt% and 40 wt% respectively. The Nano-clay was added in three levels 0, 2 and 4 wt% and the amount of coupling agent was fixed and set to 2 wt% for all treatments. The control samples were made using poly propylene material. Results: The results showed that the tensile and flexural strengths were increased by the addition 25 corncob and 75 poplar wt% particles. For tensile and flexural modulus, adding 2 wt% of nano-clay led to an increase in strength and modulus but there was a decrease when 4 wt% nano-clay was used. The impact strength increased by adding nano-clayConclusion: According to the mechanical and physical properties of all the treatments, the samples which were made of 25 corncob and 75 poplar wt% particle with 2 wt% of Nano-clay had better results compared to other samples.
Composite wood products
Mohamad Noorirad; Hedayatolah Aminian; Loya Jamalirad; Vahid Vaziri
Abstract
Background and objectives: Many studies have been conducted on the use of cellulosic resources to provide portion of raw materials for wood and paper industries. Waste branches for some species such as palm and Prosopis cineraria in southern parts of country can be a solution for deficiency of raw material ...
Read More
Background and objectives: Many studies have been conducted on the use of cellulosic resources to provide portion of raw materials for wood and paper industries. Waste branches for some species such as palm and Prosopis cineraria in southern parts of country can be a solution for deficiency of raw material in wood and paper industries. This study investigated the possibility of using a combination of Prosopis cineraria and industrial wood particles to produce particleboard with acceptable physical and mechanical properties.Methodology: The variables in this study were the ratio of Prosopis cineraria to industrial wood particles at four levels (0:100, 15:85, 30:70, 45:55) and urea formaldehyde resin at two levels (10 and 12 percent). Industrial wood particles from Sanate Choube Shomal Company and Prosopis cineraria particles were obtained from the province of Sistan and Baluchistan. Ammonium chloride as a hardener was used at 2 percent of the dry weight of the adhesive. After mixing raw material, the mat was placed under hot pressing at a temperature of 170 ˚C for 6 minutes. After the manufacture of the single-layer particleboard, the physical and mechanical properties of the boards were analyzed by a factorial test in a completely randomized design with a confidence level of 5%. Results: The results showed that the physical and mechanical properties of the panels decreased as the percentage of mixture Prosopis cineraria particles increased. So that, panels containing 45% Prosopis cineraria particles and 10% urea-formaldehyde resin had the lowest mechanical properties, while panels containing 12% urea-formaldehyde resin without Prosopis cineraria s particles had the best mechanical properties. Panels containing 45% Prosopis cineraria particles and 12% urea-formaldehyde resin had the lowest water absorption and thickness swelling, while panels containing 10% urea-formaldehyde resin without Prosopis cineraria particles had the highest.Conclusion: According to the results of this study, there was usability of boards with 15% Prosopis cineraria particles and 10% resin for Type P1 boards and the boards with 15% Prosopis cineraria particles and 12% resin for Type P2 boards.
Composite wood products
Sepideh Sasanian; Arash Farajpour Roudsari; Asghar Tabei
Abstract
Background and Objective: In the present era, technological advancement depends on the progress made in the field of materials and the production of composites has been a significant step towards the evolution of engineering materials. By physically combining two or more materials, not only lighter ...
Read More
Background and Objective: In the present era, technological advancement depends on the progress made in the field of materials and the production of composites has been a significant step towards the evolution of engineering materials. By physically combining two or more materials, not only lighter and stronger material are produced, but such new materials replace the traditional materials. This research aims to compare the mechanical and physical properties of composites coated with small glass beads and shells powder, individually and in mixture, and to select the best sample with lighter specific weight, better strength, and easier installation for building facades.Materials and Methods: The samples were prepared using beech wood flour, E-grade glass fibers, ortho unsaturated polyester resin matrix, montmorillonite K10 nanoclay, MEPK, 10% cobalt as a constant factor, Caspian Sea rolling shell (Cerastoderma glaucum) powder, and small glass beads as a variable factor. Specimens were made using the hand lay-up method. Variable percentages of glass beads and shells, or a combination of both, were used on the composite as a gel coat. Fifteen composite blocks with dimensions of 20×30×0.7 cm3 were prepared. The edges of the block were then sanded. The blocks were placed in an oven at 120 degrees centigrade for 2 hours, and after cooling, they were weighed and their dimensions were measured, and then cut to the required sizes, and physical and mechanical properties such as water absorption, thickness swelling, bending, tension, impact, and abrasion were measured using ASTM procedures with three replication. Finally, the specific weight was compared according to national building regulations. For data analysis, the SAS9.6 method was used. The validity and reliability of the test were calculated with 99% accuracy based on the test data and reported as an analysis of variance table using SAS software..Results: The results of this research showed that the sample made from a combination of nanoclay, beech wood flour, glass fibers, and resin with 30% glass beads coating demonstrate increased impact resistance. The more glass beads were added to the coating, the higher the impact resistance of the composite. With a 30% coating using Caspian Sea rolling shell powder, the composite bending and tension strength increased compared to the control sample. The abrasion rate in composites prepared with 30% glass beads and 30% shell powder was lower after 200 cycles of abrasion compared to other samples. The thickness swelling rate after 48 hours of immersion in water was zero. Although the water absorption rate in the samples was very low, it can be said that samples with a higher amount of shell powder had higher water absorption compared to the control sample. The specific weight of the samples with the dimensions of the 20×30×0.7 cm3 was measured as 1211.9 kg/m³. The highest specific weight in the treatments was related to the sample treated with a 30% glass bead layer coded G180SH0 (p=1240 kg/m³), and the lowest specific weight was related to the untreated control sample coded G0SH0 (p=1192 kg/m³). Meanwhile, the lowest specific weight of stone used for building facades belongs to quartz (p=2000 kg/m³).Conclusion: In general, it can be mentioned that the composite prepared with a 30% glass bead coating has better quality in terms of abrasion, impact resistance, strength, and no water absorption compared to other samples. From the relative comparison of the specific weight of the samples, it can also be acknowledged that with an increase in specific weight, the impact and bending strength increases, as seen in the G180SH0 sample. Ultimately, the research objective of preparing a strong and lightweight composite for building facade applications was achieved.
Composite wood products
Akbar Mastouri; Davood Efhamisisi; Asghar Tarmian; AliReza Gholinezhad-Pirbazari; Mohamad Azad fallah
Abstract
Background and objectives: Surface modification and coating is one of the effective methods to increase the performance and service life of wooden structures. All kinds of super-hydrophobic techniques with a contact angle above 150 degrees and a sliding angle less than 10 degrees, in addition to creating ...
Read More
Background and objectives: Surface modification and coating is one of the effective methods to increase the performance and service life of wooden structures. All kinds of super-hydrophobic techniques with a contact angle above 150 degrees and a sliding angle less than 10 degrees, in addition to creating high hydrophobicity, also improve the antimicrobial and other surface properties of the substrate. Nevertheless, resistance to mechanical and moisture damage are very important in connection with super-hydrophobic surfaces. Natural waxes are one of the efficient and healthy materials for creating a durable super-hydrophobic coating with high biocompatibility. In this research, nano-silica modified with non-fluorine alkyl materials in the presence of epoxy resin has been used to create superhydrophobic surfaces of birch wood (Betula pendula). Also, carnauba wax has been used to improve water repellency, self-cleaning property and durability in conditions of mechanical damage, humidity and harsh environments, comparatively.Materials and methods: Dodecyltrichlorosilane was used in the presence of toluene solvent for functionalizing and hydrophobicizing silica nanoparticles. A formulation containing 2% of modified nano silica and some epoxy resin was used by spray method to fabricate super-hydrophobic coating on birch wood. Also, the optimal amount of vegetable carnauba wax (Brazilian palm) was used as a reinforcing agent to make the nanohybrid formulation. Durability and stability to mechanical damage (sandpaper abrasion, water impact) and harsh environments (acidic, alkaline, ultraviolet rays and solvents) were investigated. Finally, the self-cleaning potential of the processed wooden surfaces was evaluated by qualitative (inclined surface) and quantitative (dropping) methods using edible liquids.Results: Both types of nanocomposite (without wax) and nanohybrid (containing wax) coatings caused the super-hydrophobicity on birch wood. The adding the optimal amount of carnauba wax to the epoxy-based nanocoating structure leads to a contact angle of 170 degrees and a sliding angle of less than 3 degrees by water drops. In addition, carnauba wax caused the stability and strength of superhydrophobic surfaces in aging and mechanical conditions. The highest level of stability in harsh environments was related to the hybrid nanocoating. The highest contact angle was observed for pomegranate juice and the lowest for milk. Also, the self-cleaning potential with various types of Fanta and Coca-Cola drinks on the superhydrophobic surface was successful.Conclusion: The use of carnauba wax increased the contact angle and decreased the sliding angle. The use of carnauba wax significantly improved the mechanical properties and water-repellency of the super-hydrophobic coating. The chemical nature and morphological structure of wax in the coating is the reason for this superiority. The super-hydrophobic surface made with nanohybrid coating in the presence of carnauba wax has the potential of self-cleaning, biocompatibility and stability in service conditions and can be used to protect all types of general surfaces in the field of food, especially lignocellulosic substrates such as wood and paper.
Composite wood products
Javad Torkaman; rouzbeh asadi khansari
Abstract
Fibre-gypsum board is a composite, in which fiber used as the reinforcement in the matrix of gypsum. The purpose of this article is to investigate the effect of different amounts of waste paper fibers on the strength, resistance and the fracture behavior of fiber-gypsum board. For this purpose, amounts ...
Read More
Fibre-gypsum board is a composite, in which fiber used as the reinforcement in the matrix of gypsum. The purpose of this article is to investigate the effect of different amounts of waste paper fibers on the strength, resistance and the fracture behavior of fiber-gypsum board. For this purpose, amounts of zero, 5, 10, 15, 20, 25 and 35 percent of waste paper fibers have been used. The results of measuring bending strength, internal bonding and moisture absorption during one month exposure to 100% relative humidity show that increasing the percentage of fibers up to 20% has increased the mechanical properties. In general, By using twenty percent fibers the bending strength increased fifty percent and the internal bonding became double and half in comparison to the control samples. The load-displacement curve shows that an increase of 5 to 15 percent of fibers does not change the fracture behavior of the fiber-gypsum board and they had brittle fracture same as control samples. While in more substitution values, the flexibility increases and the failure becomes ductile. Therefore, the best conditions in terms of strength, resistance, and flexibility have been obtained in 20% replacement of gypsum with waste paper fibers.
Composite wood products
Mohammad Hamed; Babak Nosrati; Ali Shalbafan; Mohammad Dahmardeh Ghaleno; Saeid Reza Farrokhpayam
Abstract
In recent years, the most important challenge for wood-based compact producers has been an increasing demand for a variety of wood materials, raw material prices, and rising transportation costs. On the other hand, the use of lightweight elements in the manufacture of decoration and furniture has received ...
Read More
In recent years, the most important challenge for wood-based compact producers has been an increasing demand for a variety of wood materials, raw material prices, and rising transportation costs. On the other hand, the use of lightweight elements in the manufacture of decoration and furniture has received much attention. The present study aimed at evaluating the effect of different levels of two variables on the size and amount of expanded polyurethane chips in the production of lightweight composite particle boards. To this end, the size of polyurethane particles at three levels (10, 5, and 15 mm) and their amount at four levels (10, 5, 0, and 15%) were chosen as research variables, and the amount of adhesive consumption, press pressure, board thickness, and final density were considered as fixed factors. The results showed that flexural strength, the flexural modulus of elasticity, internal adhesion, and thickness elongation increased significantly with increasing the size of polyurethane particles in the middle layer of the board, but the effect of size was not significant on the water absorption of the samples. Also, increasing the percentage of polyurethane in the middle layer increased the mechanical properties and improved the physical properties compared to the control sample, and it had the largest effect on the internal adhesion of the samples.
Composite wood products
Reza Jazayeri; Saeed Kazemi Najafi; Habibollah Younesi
Abstract
This study aimet at to use modified graphite materials as a multifunction additive in the UF resin for improving the properties of medium density fiberboard (MDF). For this purpose expanded graphite EG was synthesized from graphite using the Tsai et al (2011) method. Then, as-synthesized EG was intercalated ...
Read More
This study aimet at to use modified graphite materials as a multifunction additive in the UF resin for improving the properties of medium density fiberboard (MDF). For this purpose expanded graphite EG was synthesized from graphite using the Tsai et al (2011) method. Then, as-synthesized EG was intercalated with manganese dioxide by Schwarz et al (1995) method and converted to MnO2-EG. Any additive was added to the urea formaldehyde resin in three doses of 1, 2 and 3% to make the relevant MDF panels with 750 kg/m3 nominal density. During the pressing time, the tT100oc parameter (time to reach temperature100○C) of the middle layer of the board under the influence of the additive was determined by a chromium-nickel-based thermocouple. The treatment of MnO2-EG3 (amount of 3% modified expanded graphite) showed the greatest effect in reducing tT100°C of the middle layer of the board by 22%. In addition, the elastic modulus increased by 68% as a result of this treatment. In addition, the elastic modulus increased by 68% as a result of this treatment. G and EG additives showed a higher degree of internal adhesion than that of MnO2-EG additive. In this regard, EG2 and EG3 treatments showed a 42% increase in internal adhesion and G2 treatment showed a 40% increase in internal adhesion. The effect of EG2 treatment in improving SW24 was greater than other treatments, so that it caused a 19% decrease compared to the control.
Composite wood products
Mohammad Farsi; Asghar Tabei; Fatemeh Maashi sani; masoud ebadi
Abstract
The purpose of this research is to investigate the physical and mechanical properties of the wood-plastic nanocomposite obtained from Raw and Functionalized carbon nanotubes (CNTs). For this purpose, wood flour at a fixed amount of 50%, Raw CNTs at three levels of 0, 1 and 2% and coupling agent at two ...
Read More
The purpose of this research is to investigate the physical and mechanical properties of the wood-plastic nanocomposite obtained from Raw and Functionalized carbon nanotubes (CNTs). For this purpose, wood flour at a fixed amount of 50%, Raw CNTs at three levels of 0, 1 and 2% and coupling agent at two levels of 0 and 3% were used in HDPE matrix. Also, Functionalized CNTS were used to strengthen the efficiency of nanocomposites at 1 and 2% levels separately. The materials were mixed together in an internal mixer (Haake) and then the samples were made by a hot press machine. The results showed that by increasing the amount of CNTs from 0 to 2% wt, the tensile strength and modulus of the samples increased by 58.8% and 12.6% respectively, and water absorption and thickness shrinkage decreased by 54.5% and 19.4% respectively. Composites containing 2% wt of CNTs showed higher impact resistance compared to control samples. The coupling agent had a positive effect on the performance of nanocomposites. The physical and mechanical properties of the samples were significantly improved by adding the coupling agent and Functionalized CNTs. The results were also confirmed by scanning electron microscopy.
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 ...
Read More
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.
Composite wood products
Salume Esmaeilzadeh Saeih; Habibollah Khademi Eslam; Esmaeil Ghasemi; behzad baziyar
Abstract
Abstract Effects of temperature, cellulose Nano fibers and Nano clay particles on mechanical, physical and morphological properties of biodegradable composites made of recycled thermoplastic starch biopolymer and regular mixed industrial sawdust are investigated. To this aim Cellulose Nano Fibers and ...
Read More
Abstract Effects of temperature, cellulose Nano fibers and Nano clay particles on mechanical, physical and morphological properties of biodegradable composites made of recycled thermoplastic starch biopolymer and regular mixed industrial sawdust are investigated. To this aim Cellulose Nano Fibers and Nano Clay particles were selected to be 0, 3 and 5 weight percent and were added to prepared biodegradable composites by using internal mixer and samples prepared by injection molding. Mechanical properties including tensile modulus and strength, flexural modulus and strength were extracted at temperatures ranging from 23 ºC to 80 ºC. Impact test and water absorption and thickness swelling were also performed according to related standards. Results show that elevating the temperature drastically reduce mechanical properties. Nano Clay addition results in better mechanical properties except for impact and water absorption and thickness swelling are improved. Using 5% Cellulose Nano Fibers improves mechanical and morphological properties better than 3% addition. Dynamic mechanical thermal analysis revealed Nano composites samples with 5% Nano Clay and Cellulose Nano Fibers has higher storage modulus and glass transition temperatures in compare to pure composite samples. This Nano particles can be successfully used to improve properties and performance except for fracture resistance.
Composite wood products
Behzad Hosseini; mohammad ghofrani; Hamid Reza Taghiyari; Saman Ghahri
Abstract
In this research, Effect of soy flour addition into urea-formaldehyde resin on physical, mechanical properties and formaldehyde emission of plywood was investigated. Soy flour was mixed with urea-formaldehyde adhesive in three levels 5, 10 and 15% (based on dry weight of urea-formaldehyde adhesive) and ...
Read More
In this research, Effect of soy flour addition into urea-formaldehyde resin on physical, mechanical properties and formaldehyde emission of plywood was investigated. Soy flour was mixed with urea-formaldehyde adhesive in three levels 5, 10 and 15% (based on dry weight of urea-formaldehyde adhesive) and three-layer plywood was manufacture from the resultant adhesive and poplar veneer. Properties of manufactured plywood including formaldehyde emission according to EN-717-3 standard, shear strength according to EN-314 standard and water absorption and thickness swelling according to EN-317 standard were investigated. The results indicated that addition of soy flour up to 15% decreased formaldehyde emission up to 29.34% and increased shear strength of panels. Moreover, delamination test (According to ANSI/HPV-HPV1 Standard) presented acceptable results. The results obtained from water absorption and thickness swelling after 2h and 24h showed that addition of soy flour increased the amount of water absorption and thickness swelling. thickness swelling after 2h and 24h showed that addition of soy flour increased the amount of water absorption and thickness swelling.
Composite wood products
ali hasanpoor tichi; Fardad Golbabaei; hadi Ghasemi; mojtaba rezanezhad
Abstract
In this study, the effect of nano gel wollastonite on physical, mechanical and morphological properties of composites made of bagasse and cement has been investigated. The mixing ratio of bagasse as lignocellulosic material with Portland cement at three levels (15:85, 25: 75 and 35: 65%) and nano-wollastonite ...
Read More
In this study, the effect of nano gel wollastonite on physical, mechanical and morphological properties of composites made of bagasse and cement has been investigated. The mixing ratio of bagasse as lignocellulosic material with Portland cement at three levels (15:85, 25: 75 and 35: 65%) and nano-wollastonite at three levels of 0, 3 and 7% were considered as the variables of this study. The cake density of all boards were 1.1 g / cm3 and calcium chloride booster 5% for all treatments were considered as constant factors. Mechanical and physical properties of the specimens include modulus of rupture, modulus of elasticity, internal bonding, thickness swelling after 2 and 24 soaking hours in water and density of boards according to DIN-EN-634 and fire resistance (weight loss percentage) according to standard ISO-11925 were measured. In this study, the hydration temperature of a mixture of cement, bagasse and nano-wollastonite was measured using a thermocouple and flux. Also, microscopic images (SEM) of samples were prepared to investigate the morphological properties of composites and their distribution. The results showed that by increasing the amount of nano-wollastonite, the percentage of weight loss boards decreased, the heat of hydration and the physical and mechanical properties improved. The modulus of rupture, modulus of elasticity, and internal bonding of boards decreased with increasing bagasse content and the maximum value was obtained using 15% bagasse. The results also showed that with increasing bagasse content in boards, there was a significant increase in thickness swelling of boards. Inference from microscopic imaging (SEM) showed that the optimum level of nano-wollastonite can fill the empty holes and create a uniform structure and thus improve the properties of the boards.
Composite wood products
Mohammad Ghofrani; ali mohamadi
Abstract
This study investigated the comparative tension and compression strength of detachable edge joints in MDF and particle boards. Five pieces of each samples were provides in L shape with the size of 20*20 cm according to D 1761 ASTM. Fittings were applied in three types: cross, hexagonal shape and plastic ...
Read More
This study investigated the comparative tension and compression strength of detachable edge joints in MDF and particle boards. Five pieces of each samples were provides in L shape with the size of 20*20 cm according to D 1761 ASTM. Fittings were applied in three types: cross, hexagonal shape and plastic fitting with 2 types of counter sink and butt screw were used. The results showed that the highest amount of tension strength was in cross shape metal joints and highest compression strength in hexagonal joints. Also the lowest strength of both tension and compression was observed in plastic joints. According to results, the joints with counter sink screws had higher strength than butt screw, and the failure place in this samples was like crevice in the bottom of boards. The data showed that the tension strength of all three fittings were higher than compression strength. The highest bearing of tension stress was in MDF with glue and dowel, counter sink screw and cross shaped fitting and the lowest was in particle boards without dowel, butt screw and plastic strips. The highest bearing of compression stress was in MDF with glue and dowel joint, hexagonal metal strip and counter sink screw, the lowest was seen in particle board without dowel, butt screw, and plastic strip.
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. ...
Read More
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.
Composite wood products
Moein Dehghan; Ali Ahmadi ladjimi; Habib Dahmardeh
Abstract
DOR:98.1000/1735-0913.1398.34.63.66.1.1575.1610 In the present research the biodegradability Properties of poly-lactic acid-canola stem flour composites in three levels of 25, 35, and 45% canola stem flour made by compression molding technique were studied . In order to study the biocompatibility behavior ...
Read More
DOR:98.1000/1735-0913.1398.34.63.66.1.1575.1610 In the present research the biodegradability Properties of poly-lactic acid-canola stem flour composites in three levels of 25, 35, and 45% canola stem flour made by compression molding technique were studied . In order to study the biocompatibility behavior of the composite, three methods of biological degradation were used for Trametes versicolor and Gloeophyllum trabeum fungi, long-term water absorption and composites burial in the soil for 4 months. The results of statistical analyzes showed that the amount of composites weight loss increased against the degradation by fungi and burial in the soil by increasing the amount of rapeseed canola stem flour while pure poly-lactic acid had a very high durability against these factors. In addition, there was no effect on the weight loss of samples in the long run leach test so that the weight of composites and poly- lactic acid samples was constantly increasing and there was no effect on weight and thickness loss. The growth of myceliums fungi was clearly detectable and detectable in reviewing the images of electron microscopy from the fracture properties of composites, unlike poly-lactic acid so that fungi crossed their polymer into rapeseed shoot flour and reduced the weight of the composites. The results of the FTIR spectroscopy on poly-lactic acid prepared before and after exposure to the Gloeophyllum trabeum fungus confirmed the validity of the above results. According to the results of this study, poly-lactic acid, as a biodegradable polymer, has been shown to be very durable against degradation by natural biological agents.
Composite wood products
masoudreza habibi
Abstract
DOR:98.1000/1735-0913.1398.34.74.66.1.1578.1576 In this study, the effect of piling storage method of Bagasse was studied on the physical and mechanical properties of particleboard. Wet depitted Bagasse was used. In this study, Bagasse storage conditions included two moisture content (45% and 55%) and ...
Read More
DOR:98.1000/1735-0913.1398.34.74.66.1.1578.1576 In this study, the effect of piling storage method of Bagasse was studied on the physical and mechanical properties of particleboard. Wet depitted Bagasse was used. In this study, Bagasse storage conditions included two moisture content (45% and 55%) and 4 storage times (1.5, 3, 4.5, 6 months). At the first, Bagasse chemical properties (pH, acid and alkaline buffering capacity) were determined. Then particleboards were fabricated. The physical and mechanical properties of the boards were measured and statistically analyzed. The results showed that at lower Bagasse moisture content, the sample pH and alkaline buffering capacity were decreased and acid buffering capacity increased. Also board bending properties (modulus of rupture and modulus of elasticity) and thickness swelling after 2 and 24 hours immersion in the water were reduced. Bagasse chemical properties tend to be acidic up to storage time of 3 month and the minimum of board bending properties and internal bond were obtained in this storage time. The physical properties of boards were improved with increasing of storage time.
Composite wood products
Abbas Tamjidi; Mohamad Mehdi Faezipour; Habibollah Khademi Eslam; Ghanbar Ebrahimi; Kazem DoosthoseinI
Abstract
DOR:98.1000/1735-0913.1398.34.140.66.1.9.1586 In this study, the possibility of three-layered oriented strand board production from hornbeam (Carpinus betulus L.) wood was evaluated. Two levels of press time (6 and 8 minutes) and three levels of press temperature (180˚C, 200˚C and 220˚C) were applied ...
Read More
DOR:98.1000/1735-0913.1398.34.140.66.1.9.1586 In this study, the possibility of three-layered oriented strand board production from hornbeam (Carpinus betulus L.) wood was evaluated. Two levels of press time (6 and 8 minutes) and three levels of press temperature (180˚C, 200˚C and 220˚C) were applied and 12 mm thick laboratory boards were made from hornbeam wood. The strands on the surface layers were aligned in the long direction of the board and the middle layer strands are cross aligned to the surface layers. In all treatments, board targeted density of 0/7 g/cm3 and mat moisture content of 7% and phenol-formaldehyde resin (PF) content of 7% based on the oven dry weight of the strands were kept constant. The mechanical and physical properties of the boards were measured as defined in relevant European standards test methods EN 300. The internal bound (IB) and thickness swelling (TS24) of boards were significantly improved as the press time increased from 6 to 8 minutes. The modulus of rupture (MOR) and internal bound (IB) and thickness swelling (TS24) were significantly improved as the press temperature increased from 180˚C to 220˚C. Overall results showed that the highest MOR and IB and the lowest TS24 were achieved at 8 minutes press time and 220˚C press temperature and all boards made from this mentioned conditions exceed the EN 300 standards for MOR, MOE, IB and TS24.
Composite wood products
Laya jamali rad; saeed Narooei
Abstract
The purpose of this study was to investigate the possibility of using tobacco stalk and industrial wood particles in particleboard industry as a waste material that is not consumed and discarded and has a low price, followed by a reduction in production costs from the way of choosing this raw material ...
Read More
The purpose of this study was to investigate the possibility of using tobacco stalk and industrial wood particles in particleboard industry as a waste material that is not consumed and discarded and has a low price, followed by a reduction in production costs from the way of choosing this raw material was of low value. For this purpose, the particles of tobacco stalk and industrial wood particles with different ratios of 0:100, 30:70 and 60:40, using the amount of adhesive used 12% and 14% (based on the dry weight of the wood chips) and the press time of 5 minutes for the construction of the board was considered. Physical and mechanical properties including thickness swelling after 2 and 24 hours immersion in water and bending strength (MOR), modulus of elasticity (MOE) and internal bonding (IB) were measured and all data were statistically analyzed. According to the results of this study, the increase in tobacco stalk particles resulted in increased thickness swelling after 2 and 24 hours immersion in water and reduced bending strength, modulus of elasticity and internal bonding, but all boards had a European standard (EN). Increasing the amount of resin also had a significant effect on all the properties of the boards and improved the properties. In a general conclusion and by comparing the properties of the boards produced with the European standard (EN), showed that using 60% tobacco stalk and 12% urea formaldehyde resin can be produced particleboard with the desired properties. This is a positive result of using tobacco stalk as a type of agricultural residue and, consequently, the prevention of environmental pollution caused by the burning of these compounds.
Composite wood products
Abolfazl Kargarfard
Abstract
The of utilization corn stalk residues in combination with poplar wood for particleboard production is investigated. Four combinations of corn stalk and P.nigra particles (100% corn stalk; 75% corn stalk, 25% poplar wood; 50% corn stalk, 50% poplar wood and 25% corn stalk, 75% poplar wood) is used. Two ...
Read More
The of utilization corn stalk residues in combination with poplar wood for particleboard production is investigated. Four combinations of corn stalk and P.nigra particles (100% corn stalk; 75% corn stalk, 25% poplar wood; 50% corn stalk, 50% poplar wood and 25% corn stalk, 75% poplar wood) is used. Two resin contents of 10 and 12% and two press temperatures of 170 and 180C is employed.
The results showed that increasing press temperature from 170 to 180C, decreased both MOR and MOE of boards and increasing resin content from 10 to 12%, improved MOR. When the ratio of poplar wood to corn stalk increases, both MOR and MOE of the boards increases and the highest values were reached at 50 and 75% poplar wood. Higher press temperature and lower ratio of corn stalk improved internal bond (IB). Higher press temperature, resin content and lower ratio of corn stalk, decreased thickness swelling. Based on the results, with application of either 25 to 50% corn stalk and press temperature of 170C, standard particleboard can be produced.
Composite wood products
Abolfazl Kargarfard; Abdolrahman Hosseinzadeh; Amir Nourbakhsh; Ali Fatolahzadeh
Abstract
Particleboard industries are a dynamic industry, that has been established and grown rapidly in Iran. Demand for Particleboard has been increased rapidly due to increase population, thus the possibility of utilization residues from other wood using industries or other lignocellulosic raw materials should ...
Read More
Particleboard industries are a dynamic industry, that has been established and grown rapidly in Iran. Demand for Particleboard has been increased rapidly due to increase population, thus the possibility of utilization residues from other wood using industries or other lignocellulosic raw materials should be investigated. The boards made for this study contained Haloxylon sp. and wheat straw at 0: 100, 75: 25, 50: 50 and 25: 75 ratios as raw material. Samples of all the boards made were tested by the methods described in DIN 68763 standard, to obtain mean values of bending strength, internal bond strength (IB) and thickness swelling.The results of this study showed that there are no significant statistical differences among each combination for MOR and MOE but with increasing the percentage of wheat straw the MOR of boards was found to increase. There were statistical differences among each combination of IB wheat straw had the lowest IB, where as the highest IB were observed on the boards with 100 percent Haloxylon sp.In addition, samples of each type of board were tested for thickness swelling (T.S) after immersion in water for 2 and 24 hours respectively, and the results indicate that there were statistical differences among each combinations and the lowest thickness swelling value was belong to the boards with 100 percent Haloxylon sp. which had the highest IB. It was also observed that the board made of Haloxylon sp. and wheat straw at with 25: 75 ratio had the highest T.S immersion in water after 2 and 24 hours.
Physics and anatomy
Farshid Basiji; Vahid reza Safdari; Ahmad Jahan latibari; Amir Nourbakhsh
Abstract
The objective of adding reinforcing fillers, such as natural fibers to plastics is to increase the strength compared with neat plastic and wood. In this research the effect of wood pulp fiber length (short, medium and long), aspect ratio and fiber content (27%, 37%, 47% and 0% (non-reinforced PP)) with ...
Read More
The objective of adding reinforcing fillers, such as natural fibers to plastics is to increase the strength compared with neat plastic and wood. In this research the effect of wood pulp fiber length (short, medium and long), aspect ratio and fiber content (27%, 37%, 47% and 0% (non-reinforced PP)) with 3% maleic anhydride grafted polypropylene on wood plastic composites (WPCs) has been studied. Results showed that increased fiber length or aspect ratio and fiber content increases mechanical properties (tensile strength, tensile modulus and MOE). Impact strength had an inverse correlation with fiber content and fiber length, but fiber content was a much more important factor than fiber length for impact strength. The impact strength of composite of softwood pulps was much higher than wood floor composite plastic. The significant interaction between fiber length and fiber content, and the lack of a specific trend in the treatments made assessment of the effect of fiber properties on MOR difficult.
Composite wood products
Ashkaan Keshaavarz; Hossein Jalali Torshizi; Faranak Mohamadkazemi; Mojtaba Koosha
Abstract
Nowadays, research studies about optimal application of natural resources in products manufacturing instead of fossil and non-renewable resources are of utmost and ever growing importance. Cellulosic resources as the future reliance of Green products and also mineral mines as plenty, cheap and available ...
Read More
Nowadays, research studies about optimal application of natural resources in products manufacturing instead of fossil and non-renewable resources are of utmost and ever growing importance. Cellulosic resources as the future reliance of Green products and also mineral mines as plenty, cheap and available materials, especially in Iran, are appropriate options for various products developing. Then, effects of cellulosic fibers and Rockwool fibers (0.25% and 0.5%) in the absence and presence (0.1% and 0.2%) of nano bentonite on conventional and specific properties of Epoxy composite were evaluated. Tensile strength (47.9 MPa), modulus of rupture (86.3 MPa) and modulus of elasticity (2100 MPa) for the mineral fiber/epoxy composite and bentonite/epoxy nanocomposite were higher than the cellulosic fiber/epoxy composite. However, cellulosic fiber/epoxy composite showed higher energy absorption of the ballistic impact with lesser damage area caused by the impact than rockwool/epoxy composite which provide better protection against the ballistic impact. In the presence of nano bentonite particles into the epoxy resin context, rupture and elasticity moduli and tensile strength were dependent on the type and amounts of the additives with superiority of the mineral fibres/epoxy nanocomposite than the cellulosic fibers ones. In contrast, the composites energy absorption caused by the ballistic impact and its damaged area were more successful and favorable in cellulosic fibers than the mineral ones. Somehow that the highest absorbed energy of ballistic impact (60.7 J) and the least damaged area (10.7 cm2) were achieved by the highest application of cellulosic fibers (0.5%) and nano-bentonite (0.2%).
Composite wood products
Farhad Ghotbaldin; Habib alah Khademieslam; Amir Nourbakhsh; Mohammad Talaeipoor
Abstract
An experiment was conducted to study polymerization conditions and important production factors, the amount of resin and press temperature, on physical and mechanical properties of produced boards by urea formaldehyde (UF) and melamine urea formaldehyde (MUF) were compared. Purify UF resin (control treatment) ...
Read More
An experiment was conducted to study polymerization conditions and important production factors, the amount of resin and press temperature, on physical and mechanical properties of produced boards by urea formaldehyde (UF) and melamine urea formaldehyde (MUF) were compared. Purify UF resin (control treatment) and its mixture with MUF at 25, 50 and 75% proportions in 170 and 180˚C temperature were used to make homogen particle boards. The proportion of resin to particles was 10 percent by dry weight. Other production factors were assumed as fix factors. Eight experimental groups (treatment) with three replications per each were studied. Produced particles were derived from species Alnus subcordata. Physical and mechanical properties measurement prepared samples were based on European EN standard. Examined Physical characteristics were water absorption and thickness swelling and mechanical characteristics were modulus of rupture, modulus of elasticity and so internal bond. The data were analyzed in completely randomized design with factorial arrangement (4*2). Statistical significances among treatment means were determined by multiple range test of Duncan. The results of this study showed that physical and mechanical properties of boards were improved by increasing the level of MUF resin and temperature. Eventually, with consideration all results and so quality and economical aspects of produced particleboard by MUF resin and its comparison with control group we have concluded that 50 percent of MUF resin and 180 degree centigrade of press temperature are optimal levels.
