Composite wood products
Hossein Ahmadi; Amir hooman hemmasi; Saeed Mahdavi
Abstract
The aim of this study is investigating the mechanical properties of recycled HDPE (high-density polyethylene) filled by furfural residue produced from bagasse. For this purpose, rHDPE was used at three levels 58, 68 and 78% and furfural residue as a filler was added at levels of 20, 30 and 40%. The grafted ...
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The aim of this study is investigating the mechanical properties of recycled HDPE (high-density polyethylene) filled by furfural residue produced from bagasse. For this purpose, rHDPE was used at three levels 58, 68 and 78% and furfural residue as a filler was added at levels of 20, 30 and 40%. The grafted maleic anhydride with polyethylene (PE-g-MA) was used at constant amount of 2% as compatibilizer which prepared from Arya polymer Co. The ingredients mixed in two screw extruder and test samples were made using injection molding method. Composite properties such as tensile strength, flexural and V-notch impact were measured according to ASTM standards. The results showed that with increasing the filler content of 20 and 30% by weight, tensile modulus and flexural strength increased compared to the control and then reduced by 40 percent of filler. FTIR spectroscopy of the furfural residue and composite filled by 30% was carried out. Also, by increasing the filler content of 20 to 40% by weight, V-notch impact strength of composite decreased. FTIR spectroscopy revealed that the absorption bands of carbonyl groups (C=O) in 1750-1600 cm-1 wavelength has slightly increased in the present of maleic anhydride compatibilizer which resulted maximum increasing of mechanical properties of composite using 30% residual furfural.
Composite wood products
Amir Nourbakhsh
Abstract
This article presents the application of agricultural residues fibers (i.e., corn stalk, reed stalk, and oilseed stalk) in order to evaluate and compare their suitability as reinforcement for thermoplastics as an alternative to wood fibers. The effects of fiber loading and CaCO3 content on the mechanical ...
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This article presents the application of agricultural residues fibers (i.e., corn stalk, reed stalk, and oilseed stalk) in order to evaluate and compare their suitability as reinforcement for thermoplastics as an alternative to wood fibers. The effects of fiber loading and CaCO3 content on the mechanical properties were also studied.Overall trend shows that with addition of agricultural residues fibers, tensile and flexural properties of the composites are significantly enhanced. Oilseed fibers showed superior mechanical properties due to their high aspect ratio and chemical characteristics. The order of increment in the mechanical properties of the composites is oilseed stalk > corn stalk > reed stalk at all fiber loadings. The tensile and Impact properties of the composite significantly decreased with increasing CaCO3 content but flexural modulus increased, due to the reduction of interface bond between the fiber and matrix. It can be concluded from this study that the used agro-waste materials are attractive reinforcements from the standpoint of their mechanical properties.
Composite wood products
Hossein Rangavar
Abstract
One of the major problems in wood gypsum particleboard production, faster hydration and thus reducing its physical and mechanical properties. In order to increase the curing time of gypsum, was used from flour glue in wood gypsum particleboard production by using of canola wastes and poplar particles ...
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One of the major problems in wood gypsum particleboard production, faster hydration and thus reducing its physical and mechanical properties. In order to increase the curing time of gypsum, was used from flour glue in wood gypsum particleboard production by using of canola wastes and poplar particles wood. To assess the time of setting of gypsum, the Vicat Needle was used based on the ASTM C191. For this purpose, pure gypsum paste and the pastes with ratios of 0, 0.1, 0.2, 0.3, 0.4 and 0.5 % flour glue to dried gypsum were settled in the mentioned device, then the setting time was determined. Thus amount 0.1% flour glue was selected on the manufacturing of wood gypsum particleboard. To evaluate the effects of flour glue and canola straw wastes on the physical and mechanical properties wood gypsum particleboard, two levels of flour glue (0 and 0.1 %) compared to the mass of the gypsum and the amount of canola straw wastes in 5 levels including (0, 25, 50, 75 and 100%) compared to the mass of poplar particles wood as a research variable factors were considered. Density of boards was 0.9 gr/cm3 and their thickness was 16 mm. The test specimens were prepared for measuring their physical and mechanical properties according to EN standard. Results obtained showed, flour glue lead to increase in gypsum hydration time and improved all of the physical and mechanical properties of wood gypsum particleboard. Also using of canola stem wastes increased value of water absorption & thickness swelling at 2 and 24 hours immersion. Flexural strength and modulus of elasticity of the boards were increase, up to 25% canola wastes compared with dry mass of poplar particles wood, however internal bond of the boards were decreased by the increasing the amount of the canola wastes.
Composite wood products
Sajad Akbari; Morteza Nazeryan; Saeid reza Farokhpayam; Babak Nosrati sheshkal
Abstract
In this study the possibility of using canola stalks mixed with poplar wood in the manufacture of particleboard was investigated. Weight ratio of canola particle to poplar particles at five levels (98, 93/75, 87/50, 81/25, 77%), the weight ratio of the urea-formaldehyde/melamine formaldehyde resin as ...
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In this study the possibility of using canola stalks mixed with poplar wood in the manufacture of particleboard was investigated. Weight ratio of canola particle to poplar particles at five levels (98, 93/75, 87/50, 81/25, 77%), the weight ratio of the urea-formaldehyde/melamine formaldehyde resin as a adhesive at five levels (23, 18/75, 12/50, 6/25, 2%) and moisture content of matt at five levels (10, 12, 15, 18, 20%) were selected as production variables. Mechanical properties of boards consist of MOR, MOE and IB was tested. According to the results, with increasing the canola stalks/poplar particle ratio MOR and MOE of the boards decreased, but all of the values obtained from treatments were higher than standard. Interaction effect analysis of variables showed that the increasing the ratio of melamine formaldehyde/urea formaldehyde resin decreased the bending strength, while the increasing the moisture of mat increased MOR and MOE. IB values of all treatments are lower than the standard. According to the results of response surface methodology (RSM) and interaction effect between studied variables on the mechanical properties of the panels, the best situation for producing the panels was selected as: weight ratio of 84/32 for canola/poplar particle, ratio of 6/25 for UF/MF resin and moisture content of 12% for mattress.
Composite wood products
Abdollah Najafi
Abstract
In this study, chemical treatments of rice husk flour on physical and mechanical properties of rice husk flour / high density polyethylene composites were studied. Rice husk was milled and its flour through the sieve of 60 meshes was selected for using. Initially, dried rice husk flour was subjected ...
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In this study, chemical treatments of rice husk flour on physical and mechanical properties of rice husk flour / high density polyethylene composites were studied. Rice husk was milled and its flour through the sieve of 60 meshes was selected for using. Initially, dried rice husk flour was subjected to chemical treatment with acetic acid and then, was mixed with powder of high density polyethylene at weight ratio of 60% filler loading in an internal mixer. After milling of mixed matreials, samples of composites were made by injection moulding method. Physical and mechanical properties of treated rice husk flour / high density polyethylene composites were compared to untreated composite and a composite including a PE-g-MA coupling agant (MAPE) that were produced in the same method. Dynamic Mechanical-Thermal Analyze (DMTA) of specimens in the temperature range of -50 to +150 ◦C were taken and storage modulus and loss modulus were measured. FT-IR spectra of chemical treatments of rice flour husks were also investigated to what extent changes in the functional groups being studied. Results of FT-IR indicated that the chemical treatment of rice husk led to a change of OH group absorbance on 3436 cm-1 and a peak in the region of 1741 cm-1 related to functional group of C=O. Results of tests also indicated that all of properties in composites including of treated rice husk flour with acetic acid were improved.
Composite wood products
Fatemh Rezaei; Ali akbar Enayati
Abstract
In this research, the effect of vine pruning fibers in combination with wood fibers on contact angel (wettability) and surface bond strength of medium density fiberboard was studied. One layer laboratory panels with a thickness of 15 mm and density of 650 Kg/Cm3 were produced. Variable factors were vine ...
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In this research, the effect of vine pruning fibers in combination with wood fibers on contact angel (wettability) and surface bond strength of medium density fiberboard was studied. One layer laboratory panels with a thickness of 15 mm and density of 650 Kg/Cm3 were produced. Variable factors were vine pruning fibers content in three levels of 0/100, 30/70 and 60/40 by weight and press time in three levels of 4, 5 and 6 minutes. The wet ability and surface bond strength of panels were measured. Results showed that the contact angle of the boards was reduced when the vine pruning fibers content increased up to 60%. Press time had significant influence on wet ability of test panels. So that the contact angle was increased with increasing the press time up to 5 minutes. Whereas the contact angle was reduced when the press time of panels increased to 6 minutes. In addition, the results indicated that the sanding of panels caused a decrease of contact angle in the boards. Moreover the surface bond strength of panels were reduced with adding vine pruning fibers up to 30% whereas the panels produced using 60% vine pruning fibers showed stronger.
Composite wood products
Fardad Golbabaei
Abstract
The main purpose of the production of cement or wood products, composite panels by binding mineral particles mixed with organic materials such as wood and mineral lignocellolosic connectors such as cement, plaster, etc. This study was conducted with the objective of investigating the feasibility of making ...
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The main purpose of the production of cement or wood products, composite panels by binding mineral particles mixed with organic materials such as wood and mineral lignocellolosic connectors such as cement, plaster, etc. This study was conducted with the objective of investigating the feasibility of making wood-cement using Poplar sawdust and Portland cement. A total of 30 bricks were made in the laboratories of Wood and production based on ratios of sawdust to cement (5-95, 10-90, 15-85, 25 -75 persent). Mass and volume of samples were measured and then density of bricks was calculated. The composites were tested for compressive strength using testing machine. The mean compressive strength values were 1.75 and 0.38 MPa composites with sawdust to cement ratios of 5-95 and 25-75 respectively, soaked composites swelled irrespective of the sawdust to cement ratio. The compressive strength for the soaked bricks was approximately 40% of the dry weight strength. The composite bricks were found to be unfit for paving and medium heavy load wall construction. Due to their light weight, by imparting decorative mosaics they can be used for interior wall paneling and decoration, where minimal wetting is experienced
Composite wood products
Hossein Rangavar; Seid asghar Alavi seresht
Abstract
This research was conducted to investigate the effect of nano-wollastonite and the use of polymers polyvinyl chloride and heavy polyethylene on the fire resistance of particleboard with three layers made of pepper stalk and industrial wood particles. Urea-formaldehyde adhesive with concentration of 12% ...
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This research was conducted to investigate the effect of nano-wollastonite and the use of polymers polyvinyl chloride and heavy polyethylene on the fire resistance of particleboard with three layers made of pepper stalk and industrial wood particles. Urea-formaldehyde adhesive with concentration of 12% containing nanowollastonite with mixing ratio of 10% (based on dry mass of wood material) was used. The board in three levels matched (mixture industrial wood with pepper stalk particles), in the form of three layers, include the core layer pepper stalk particles and the surface layer of industrial wood particles, the core layer industrial wood particles and the surface layer of pepper stalk particles and two levels of heavy polyethylene and polyvinyl chloride polymers and nano in the two levels (with nano and without nano) were considered variable factors. Test specimens for examination of characteristics of fire resistance boards were made to include ignition timing(s), fusion time(s), weight loss(%) and carbonized area(mm2) each in two times of 2 and 30 minutes in accordance with the ISO 11925 standard was prepared and evaluated. The results showed that the use of nano-wollastonite and polyvinyl chloride and heavy polyethylene polymer and the boards were improved fire resistance .In particular, heavy polyethylene polymer has a better effect on the fire resistance of the boards. Three layers boards with industrial wood particles on the surface had a long ignition and fusion time. Moreover, percentage of weight loss and carbonized area in a three layer boards with pepper stalks particles on the surface were low
Composite wood products
Mohsen Saffari; mohammad reza ranjbar; mohammad ali ghavidel; abdollah hosseinzadeh
Abstract
AbstractThe aim of present study was to determine the relationship between ultrasonic wave velocity and mechanical properties of particleboard panels. For this purpose, homogenous and layering particleboards were made by 0/7 g/cm3 density and 16 mm thickness. After conditioning and preparing samples, ...
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AbstractThe aim of present study was to determine the relationship between ultrasonic wave velocity and mechanical properties of particleboard panels. For this purpose, homogenous and layering particleboards were made by 0/7 g/cm3 density and 16 mm thickness. After conditioning and preparing samples, ultrasonic wave velocity was measured in different directions of samples. Then modulus of elasticity, modulus of rupture and internal bonding of samples were measured by mechanical test machine. Result indicated that ultrasonic wave velocity of particleboard samples was higher in longitudinal direction than other directions. Relationship between ultrasonic wave velocity and mechanical properties was determined by linear correlation regression. Correlations between ultrasonic wave velocity and modulus of elasticity, modulus of rupture and internal bonding were significant in thickness direction of particleboard samples. Correlations between ultrasonic wave velocity and modulus of elasticity, modulus of rupture and internal bonding were significant in thickness direction of particleboard samples. Correlations between ultrasonic wave velocity and modulus of elasticity, modulus of rupture and internal bonding were significant in thickness direction of particleboard samples.
Physics and Mechanical Wood
Ardlan Doreemam; Vahidreza Safdari; Abolfazl Kargarfard; Ajang Tajdini
Abstract
In this study, the effect of using waste of Alnus subcordata and Poplar wood in manufacturing particle board was investigated. The particle boards were produced by adding (0-25-50-75-100)% alder branches with poplar wood and two press temperatures 170°C and 180 °C. In total, 30 particleboards ...
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In this study, the effect of using waste of Alnus subcordata and Poplar wood in manufacturing particle board was investigated. The particle boards were produced by adding (0-25-50-75-100)% alder branches with poplar wood and two press temperatures 170°C and 180 °C. In total, 30 particleboards (10 treatments with 3 replications) were made and data was analyzed with complete randomized design. Results showed that particleboards which were made of 75% alder branches and 25% poplar wood with press temperature of 180 °C had the most flexural strength. In addition, this study manifests that the increase of alder branches up to 25% led to the enhancement of modulus of elasticity of particle boards while adding more than 25% caused in the decrease of the modulus of elasticity. The increase of alder branches would augment the internal bounding and thickness swelling of particleboards. Therefore, the particleboards of 100% alder branches had the best internal bonding. However, this research concluded that the press temperature would not any significant effects on mechanical and physical characteristics.
Composite wood products
Hossein Hosseinkhani
Abstract
In this study, chemical properties of Date Palm residues including cellulose and hemi cellulose content, Lignin content, Extractive and Ash content were determined, and also its physical properties including fiber dimension were measured according to D-2395 ASTM method. The boards made for this study ...
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In this study, chemical properties of Date Palm residues including cellulose and hemi cellulose content, Lignin content, Extractive and Ash content were determined, and also its physical properties including fiber dimension were measured according to D-2395 ASTM method. The boards made for this study contained 25% lignocellolosic material, Date Palm pruning residues (both fibers and chips) and 75% Gypsum powder. Variable factors were lignocellolosic materials (fibers and chips at different proprotion (0:100, 5:95, 10:90, 15:85, and 20:80). Totally, 15 boards were manufactured, and samples of all the boards made were tested after curing for 14 days by the methods of Japanese Industrial Standard - R9111 to obtain mean values of Bending strength (MOR), Bending stiffness (MOE), Internal bond strength (I.B), thickness swelling (TS) and water absorption (WA). Gypsum particleboard (GPB) has high thickness swelling (TS), high water absorption (WA), and low mechanical properties compared with GPB reinforced fibers. The properties of GPB were improved by adding fibers. The experimental results showed that GPB with the added fibers had good physical and mechanical properties compared with those of gypsum particleboard with no added fibers. On the other hand, based on the achieved results both mechanical and physical properties of boards increarse with increasing the fiber proprotion. It can be concluded that Date palm fibers are a good material as reinforcement for the manufacture of Gypsum bounded board.
Composite wood products
Amir Nourbakhsh; Abolfazl Kargarfard
Abstract
The main objective of this research was to study the potential of bagasse fibers as reinforcement for thermoplastics as an alternative to wood fibers. The effects of three grades (Eastman G-3003, G-3015 and G-3216) of coupling agents on the mechanical properties were also studied. In the sample preparation, ...
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The main objective of this research was to study the potential of bagasse fibers as reinforcement for thermoplastics as an alternative to wood fibers. The effects of three grades (Eastman G-3003, G-3015 and G-3216) of coupling agents on the mechanical properties were also studied. In the sample preparation, one level of fiber loading (40 wt.%) and three levels of coupling agent content (0, 2 and 4 wt.%) were used. For overall trend, with addition of three grades of the coupling agents, tensile, flexural and impact properties of the composites significantly improved, as compared with untreated samples. In addition, morphological study (SEM) revealed that the positive effect of coupling agent on interfacial bonding. The composites treated with G-3216 gave better results in comparison with G-3003 and G-3015 in which, There are some voids where the fibers have been pulled-out. The presence of these voids means that the interfacial bonding between the fiber and the matrix polymer is weak. This could be caused by the high melt viscosity of G-3216 Coupling agent.
Composite wood products
Ghoncheh Rassam; Hosein Rangavar; vahid nickhah
Abstract
In this study the effects of aluminum dioxide (Al2O3) and copper oxide (CuO) metallic nanoparticles, on the physical and mechanical properties of medium density fiberboard (density of 0.7 g/cm3) made with mixture of industrial wooden fibers and sunflower plant stalk fibers were studied. Two levels of ...
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In this study the effects of aluminum dioxide (Al2O3) and copper oxide (CuO) metallic nanoparticles, on the physical and mechanical properties of medium density fiberboard (density of 0.7 g/cm3) made with mixture of industrial wooden fibers and sunflower plant stalk fibers were studied. Two levels of raw material including industrial fibers and sunflower stalks fibers, with five levels of mixing ratios (100: 0, 0:100, 50: 50, 25: 75, 75: 25), metallic nanoparticles with concentration of 400 ppm each at two levels of 2 and 4 percent (based on dry fiber weight) were used. Physical and mechanical properties including thickness swelling, water absorption after 2 & 24 hours soaking in water, modulus of rupture, modulus of elasticity of bending and internal bonding of the samples were measured and analyzed statistically. The results showed that higher percentage of nanoparticles and industrial fibers and lower percentage of sunflower stalk fibers increased the modulus of rupture and modulus of elasticity. Applying nano-metal treatment reduced water absorption and thickness swelling after 2 and 24 h soaking in water. In overall, using 4% nano aluminum dioxide and 4% nano copper oxide at all levels of mixing ratios were resulted in producing boards with better properties, comparing to the EN 622-5 standard specifications, which are suitable for interior uses.
Composite wood products
babak Nosrati; masih masoudifar; mohamad haghpanah
Abstract
Cordia (Sepestan in Persian) species (Cordia myxa L.) is in the borage family (Boraginaceae) and it is growing with geographical distribution in the moderate and tropical regions of Iran such as near the Persian Gulf, especiallyin Bandar Abbas and some places in Kerman and Sistan and Baluchestan region ...
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Cordia (Sepestan in Persian) species (Cordia myxa L.) is in the borage family (Boraginaceae) and it is growing with geographical distribution in the moderate and tropical regions of Iran such as near the Persian Gulf, especiallyin Bandar Abbas and some places in Kerman and Sistan and Baluchestan region but its anatomical characteristics have not been studied yet. In this study, some of the anatomical, chemical and physical properties of Sepestan wood in Iranshahr region in Sistan and Baluchestan Province were measured. Anatomical studies showed that this species has average diameter vessels, simple vascular perforation plate and intervessel pits alternate. Its ray xylems type is heterogeneous and contains abundant crystals. The wood tissue is parenchyma with abundant prismatic crystals and in the cross-section parenchyma was observed in gregarious and continuous formation. Average length, overall diameter, lumen diameter and wall thickness of the fibers were measured 1329, 33.5, 21.7 and 5.9 microns respectively. Also investigation of chemical characteristics showed that Sepestan wood has average cellulose 34.75, lignin 20.6, extractives soluble in acetone 7.88 and also 8.9 percent ash. The results also showed that the specific gravity of the wood is 0.4 and maximum volumetric swelling and shrinkage were 10.98 and 12.34 percent respectively.
Composite wood products
masih masoudifar; Babak Nosrati; Hamid reza Mansori; Rahim Mohebi gargari
Abstract
This study aimed to investigate the effect of chemical treatment of wood material on functional properties of wood flour / polypropylene hybrid composite. For this reason, first of all, mixed hardwood were separately treated by acetic acid, sodium hydroxide and hot water and were compared with control ...
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This study aimed to investigate the effect of chemical treatment of wood material on functional properties of wood flour / polypropylene hybrid composite. For this reason, first of all, mixed hardwood were separately treated by acetic acid, sodium hydroxide and hot water and were compared with control (untreated) samples. After chemical treatment, wood flour and polypropylene with weight ratio of 50 to 50 and 3 phc of compatibilizer combines in the internal mixer and at last the WPC composite were made using injection molding. Then mechanical tests included bending resistance, tension and impact and physical examination, including water absorption and thickness swelling after 2 and 24 hours was performed on specimens according to (ASTM) standard. Also to study the morphology of the composites, scanning electron microscopy (SEM) was used. The results of this study showed that by chemical treatment the mechanical strength increased and physical properties such as water absorption and thickness swelling decreased. So that the highest flexural strength, tensile and flexural modulus is related to alkali treatment and the highest tensile modulus and impact resistance is related to the acid treatment. Also the lowest water absorption and thickness swelling was related to the alkali treatment. In order to ensure chemical treatments, Fourier transform infrared (FTIR) and weight percent gain (WPG) was used on wood flour.
Composite wood products
Saeed Khojasteh Khosro; Saeed Khojasteh Khosro; Mohammad Hasan Payan; Seyyed Mehdi Seyydi
Abstract
In the present research improvement of dimensional stability and mechanical properties of gypsum particleboard by using white cement was investigated. In manufacturing gypsum particleboard, Micronize gypsum was used in three levels of 2.5:1, 2.75:1 and 3:1 to dried mass of wooden materials. White cement ...
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In the present research improvement of dimensional stability and mechanical properties of gypsum particleboard by using white cement was investigated. In manufacturing gypsum particleboard, Micronize gypsum was used in three levels of 2.5:1, 2.75:1 and 3:1 to dried mass of wooden materials. White cement was added in 2 levels of 5 and 10% based on oven dried mass of gypsum to reinforce gypsum particleboard properties. Water absorption, thickness swelling after 2 and 24 hours immersion in water, bending strength, modulus of elasticity and internal bond strength were measured. Vicat needle method was used to investigate the effect of adding cement on setting time of gypsum. The results showed that adding 5% cement based on oven dried mass of gypsum, increased setting time and also mechanical properties. Adding cement over than 5% (10%), significantly improved dimensional stability but reduced setting time of gypsum and mechanical properties of the boards. On the other hand, results indicated that using Micronize gypsum to 2.75 times to dried mass of wooden materials, increased bending strength and modulus of elasticity. Increasing gypsum in to 3 times, reduced bending strength and modulus of elasticity, but improved internal bond strength and dimensional stability.
Composite wood products
mahdi abasyan; asghar omidvar; mahdi mashkour; zinat farhadi
Abstract
This study seeks to investigate the possibility of producing polypropylene composite- cotton stalk flour with various percentages of cotton stalk flour. Determining the best treatment in terms of physical and mechanical properties and exploring the effect of using cotton stalks in the production of the ...
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This study seeks to investigate the possibility of producing polypropylene composite- cotton stalk flour with various percentages of cotton stalk flour. Determining the best treatment in terms of physical and mechanical properties and exploring the effect of using cotton stalks in the production of the composites were among the major objectives of this study. Six treatments consisting of Polypropylene, 40, 55 and 70 percent level of cotton stalks and two fillers (cotton stalks with and without barks) were developed. Maleic anhydride modified polypropylene (3% wt) was applied to each treatment. The mixing and granulation of the plastic and cotton silk flour was carried out using twin screw extruder model 4815. After preparing and shearing of samples, the mechanical properties of composites including tensile strength, rupture modulus and elasticity modulus were calculated in accordance with D-6109 and ASTM D-7031 standards. In addition, water absorption and thickness swelling tests were performed according to D-570-98 standard. The results showed that an increase in the flour of cotton stalk reduced the tensile strength and rupture modulus on the one hand, and increased the bending elasticity modulus on the other hand. In terms of the performance of the filler, there was a significant difference between values of rupture modulus and elasticity modulus at 95% level whereas this difference was not significant for tensile strength. Moreover, this difference was significant for values of water absorption and thickness swelling. The maximum tensile strength belonged to T4 with 40 percent of cotton stalk bark fibers.
Physics and Mechanical Wood
Ehsan Haji rafiriha; Mehran Roohnia; Ahmad Jahan latibari; Ajang Tajidini
Abstract
The effect of lamination and adhesive coverage rate in layered products made from Poplar wood was studied The effect of lamination and adhesive coverage rate in layered products made from Poplar wood was studied by non-destructive free vibration test. 120 samples with nominal dimensions of 2.5×2.5×45 ...
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The effect of lamination and adhesive coverage rate in layered products made from Poplar wood was studied The effect of lamination and adhesive coverage rate in layered products made from Poplar wood was studied by non-destructive free vibration test. 120 samples with nominal dimensions of 2.5×2.5×45 cm without any obvious deficiencies were selected and free flexural vibration in free-free bars were performed for testing them. Samples were longitudinal cut in three thinner tangential layers and jointed together again using Poly Vinyl Acetate glue. The specimens were divided into four groups according to adhesive coverage rates, which one group was fully glued and 3 groups were carrying some glue deficiencies in different rates. Manipulated samples were tried again in above mentioned test. Results indicated that shear moduli compare to modulus of elasticity is a more sensitive parameter to evaluate glue efficiency in laminated beams but concerns remained due to blind points in flexural vibration nondestructive method.
Composite wood products
Elham Ostadi; Jalil Morshedian; Yosef Jahani
Abstract
In this research the influence of using waste Poly Ethylene Terephthalate on the mechanical and rheological properties of wood flour filled PP composites has been studied. PET contents varied from 10-33 wt%. Mechanical properties were characterized by tensile testing, while their fracture resistance ...
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In this research the influence of using waste Poly Ethylene Terephthalate on the mechanical and rheological properties of wood flour filled PP composites has been studied. PET contents varied from 10-33 wt%. Mechanical properties were characterized by tensile testing, while their fracture resistance was determined by impact measurements. The melt rheological behavior of the composites was also studied by a rheometer in the oscillatory mode and dynamic rheological properties such as complex viscosity, storage modulus, loss modulus and damping factor were evaluated at190°C. The results showed that stiffness increases by adding waste Poly Ethylene Terephthalate. PET when added in low concentrations, caused tensile strength to be lower than that of PP composites filled with pure wood flour. Increasing the concentration of waste PET, led to composites with higher amount of tensile strength. The samples containing waste PET had higher complex viscosity and storage modulus than composite without PET. Likewise, it was observed that the damping factor in the PP/Wood composite decreased by incorporating waste PET to the compositions. Key words: waste polyethylene terephthalate, polypropylene, wood flour, mechanical properties, rheological behavior
Composite wood products
Hossein Hosseinkhani
Abstract
Iran is not rich in forest land and only 7.5 per cent of country covered by forest. So Iran has to import wood based panel annually. It is estimated that 100.000.000 Date Palms trees covered an area at about 770.000 ha around world, and Iran has got 220.000 ha. Because of several reasons Date palm trees ...
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Iran is not rich in forest land and only 7.5 per cent of country covered by forest. So Iran has to import wood based panel annually. It is estimated that 100.000.000 Date Palms trees covered an area at about 770.000 ha around world, and Iran has got 220.000 ha. Because of several reasons Date palm trees should be pruned and each tree produce 10-20 kg residues annually. In this study, for making boards Date Palm pruning residues as raw material and employed UF resin as the binder. Steeming time (5 and 8 Min.), steeming time (135 and 145oC) and press time (1, 2 and 3 Min.) were used as variable factors and three boards were made in Pilot plant scale for each combination of variables. Samples of all made boards were tested by the methods of EN to obtain mean values of bending strength, and Internal bond strength (I.B). In addition samples of each type of board were tested for thickness swelling after soaking in water for 2 hours and 24 hours respectively. The results of this study show clearly that boards have higher mechanical properties than the MDF property requirements which is recommended by EN standard.
Physics and Mechanical Wood
Hamideh Abdolzadeh; Ghanbar Ebrahimi; Mohammad Layeghi; Mehdi Ghasemieh; Seiad Ahmad Mirshokraei
Abstract
In this study, characteristics of wood-polymer fracture under mode I were investigated by double cantilever beam. In this regard, the properties of furfurylated specimens with three different levels of furfurylation (20%, 30% and 65%) were evaluated in both RL and TL systems. Results indicated that load-displacement ...
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In this study, characteristics of wood-polymer fracture under mode I were investigated by double cantilever beam. In this regard, the properties of furfurylated specimens with three different levels of furfurylation (20%, 30% and 65%) were evaluated in both RL and TL systems. Results indicated that load-displacement curves from mode I fracture specimens were changed by furfurylation so that it was much clear on curves of TL system. These changes not only included curve slope in elastic and proportional limit zones, but also fracture zone and initiation of crack growth were included . Furthermore furfurylation and raising its content on both systems and especially on TL one, caused to change in stress intensity factor, KIC , and critical energy release rate , GIC. In both systems GIC were highly increased by increasing of furfurylation contents. This criterion demonstrated that the wood- polymer showed much toughness under mode I fracture. Moreover, variation of KIC values due to furfurylation at both systems was different with that of GIC. At the RL system, ascending trend was observed at KIC and GIC values by increasing furfurylation levels. But at TL system, KIC was decreased by furfurylation and this criterion enhanced by increasing of furan polymer in the cell wall. Generally, results of this research show that fracture toughness of wood is highly affected by furfurylation process
Composite wood products
Samaneh Mir; Saeid reza Farokh payam; Morteza Nazerian
Abstract
In this study the possibility of using urea formaldehyde and melamine urea formaldehyde with different ratios of formaldehyde and melamine for manufacture lightweight particleboard by expanded polystyrene (EPS) was investigated. Experimental panels were made with 30 percent lighter that common particleboard ...
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In this study the possibility of using urea formaldehyde and melamine urea formaldehyde with different ratios of formaldehyde and melamine for manufacture lightweight particleboard by expanded polystyrene (EPS) was investigated. Experimental panels were made with 30 percent lighter that common particleboard in 25 millimeters thickness and with wood particles that had been came from a factory. Urea formaldehyde and melamine urea formaldehyde with two ratios different of melamine to urea, 40 to 60 and 20 to 80 were types of adhesive. Analysis of data and obtained averages on physical and mechanical properties indicated the best combination of EPS and used resins. Amino plastics adhesives showed good compatibility result with expanded polystyrene. As reducing of the weight of the panel was the most important target in this work, internal bonding (IB) result showed it was done. Because there was no any chemical reaction between EPS and phenolic resin as adhesive, it’s using was unsuccessful. Preliminary results especially internal bonding and physical properties revealed this lightweight panel is proper for defined applications. Furthermore, using melamine urea formaldehyde as adhesive was positive effects on IB and the highest IB was for the panel made with this resin and minimum EPS content. In comparison of common panels, this new panel with maximum melamine content and hydrophobic EPS showed better results on IB and physical properties.
Composite wood products
Aliakbar Aenayati; Halimeh Pangh; Mahammad Layeghi; Kazem Doosthosseini
Abstract
This study was conducted to investigate the effect of Cu nano particles addition on the density profile and mechanical properties of medium density fiberboard. One layer fiberboard (MDF) with the density of 0.58g/cm3and thickness of 17 mm were produced using Cu nano particles in three levels (5, 10 and ...
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This study was conducted to investigate the effect of Cu nano particles addition on the density profile and mechanical properties of medium density fiberboard. One layer fiberboard (MDF) with the density of 0.58g/cm3and thickness of 17 mm were produced using Cu nano particles in three levels (5, 10 and 15wt%based on solid content of resin) and urea formaldehyde resin content in two levels (8 and 10wt%based on oven dry weight of fibers) as variable factors. The control panels were produced using 10% resin (based on oven dry weight of fibers) without Cu nano particles using the identical manufacturing parameters as other panels. Mechanical strength including internal bonding (lB), bending strength, modulus of elasticity and density profile using slicing method were determined. The results indicated that increasing the content of Cu nano-particles had no significant effect on the internal bonding as well as bending strength and modulus of elasticity of panels. Increasing the resin content from 8 to 10 percent improved modulus of elasticity (43.7%), bending strength (18.9%) and internal bonding (23%) of panels. In addition, the increasing Cu nano particles up to 5% caused relatively higher IB for panels produced using 8%resin compared to the control panels(containing10% resin) as well as the density profile was more uniform with the lowest differences between maximum and minimum density in the density profile.
Composite wood products
Zahra Jahanilomer; Saeed Reza farrokhpayam; Mohammad Shamsian
Abstract
Abstract In this study, GMDH neural network based on genetic algorithm was used to predict the physical and mechanical properties of laboratory made particleboard. To predict the mechanical and physical properties of particleboard we used input parameters such as neural network including press closing ...
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Abstract In this study, GMDH neural network based on genetic algorithm was used to predict the physical and mechanical properties of laboratory made particleboard. To predict the mechanical and physical properties of particleboard we used input parameters such as neural network including press closing time (10,20 and 30 seconds), moisture content of the mat (8,10,12 and 14%) and press temperature (150,160,170 and 180°C) as the input data and the output data was the physical and mechanical properties. The efficiency of these techniques was evaluated with statistical criteria of mean square error (MSE), root mean square error, (RMSE), mean absolute deviation (MAD) and the correlation coefficient (R2). Results showed that the value of MSE, RMSE and MAD for MOR, IB, TS24h, TS2h, WA2h and WA24h is low. Errors obtained for the MOE model were very high. According to the results obtained, this model is not the appropriate for prediction of MOE. R2 values from the test and training set properties for MOR, IB, MOE, TS24h, TS2h, WA2h and WA24hwas more than 0.91%, which reflects that the performance of these models is better.
Composite wood products
Hossein Rangavar; Mohammad hassan Payan
Abstract
In this study sound absorption coefficient and hardness of gypsum particleboard produced with kenaf stalk and nano clay were investigated. Variables in this study were weight ratio of kenaf stalks to poplar wood in three levels (40, 50 and 60 %) and nano clay content (0, 3 and 6%) based ...
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In this study sound absorption coefficient and hardness of gypsum particleboard produced with kenaf stalk and nano clay were investigated. Variables in this study were weight ratio of kenaf stalks to poplar wood in three levels (40, 50 and 60 %) and nano clay content (0, 3 and 6%) based on dried mass of wooden particles. Sound absorption coefficient determined according to ISO 10534-1 and hardness was measured in accordance with the ASTM D-1037 standards. The sound absorption coefficient was measured at four frequencies of 250, 500, 1000, and 2000 Hz. The obtained results showed that with increasing frequencies, sound absorption coefficient increased. With increasing ratio of kenaf stalk in boards, hardness decreased, but sound absorption increased. Furthermore, increase in percentage of nano clay used in the boards increased the hardness and reduced the sound absorption in coefficient in gypsum particleboard. Generally, the highest sound absorption coefficient was shown the boards produced with 60% kenaf and without nano clay in frequencies of 2000 Hz.
