Ali Hasanpoor tichi; Hadi Gholamiyan
Abstract
In this study , Effect of nano cellulose Fiber gel bacteria as reinforcer on physical, mechanical and morphological properties of composites made of bagasse and cement has been studied. Nano variable factors in three levels (0, 1 and 3 % by weight of cement), the mixing ratio of bagasse as lignocellulosic ...
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In this study , Effect of nano cellulose Fiber gel bacteria as reinforcer on physical, mechanical and morphological properties of composites made of bagasse and cement has been studied. Nano variable factors in three levels (0, 1 and 3 % by weight of cement), the mixing ratio of bagasse as lignocellulosic material with Portland cement, in three levels (90:10, 80:20, 70:30%) was equal to the dry weight of cement. The target density 1.1 g/cm3 and 5% calcium chloride for all treatments were considered as Fixed factors. The mechanical and physical properties of composites includes modulus of rupture, modulus of elasticity, internal bonding, thickness swelling after 2 h and 24 h immersion in water and density of boards were measured according to the standard DIN-EN-634. In this study, to investigate the morphological properties of composites and how to distribute Nano, microscopic images (SEM) were taken from the broken cross-section of the samples. The results showed that boards made with nano fiber cellulose had more modulus of rupture, modulus of elasticity and internal bonding. The results also showed that with increasing nano, density, dimensional stability of the boards and heat hydration of cement mortar increased. The results from microscopic imaging (SEM) showed that cellulose nanofiber can fill the pores of the composite and create a uniform structure, thus improved the strength of the boards.
Mohammad Reza topa esfandiyari; Mohammad Talaei poor; Habibollah Khademi Eslam; Seeyed Ahmad Mirshokraie; behzad baziyar
Abstract
This study uses soda lignin to modify it with furfural as adhesive on the physical and mechanical properties of plywood Poplar wood. Producing plywood, pure Lignin (L.100%), lignin-furfural 30% (L.70-F.30), lignin- furfural 60% (L.40-F.60) were used as the adhesive at three different levels ( 120 140 ...
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This study uses soda lignin to modify it with furfural as adhesive on the physical and mechanical properties of plywood Poplar wood. Producing plywood, pure Lignin (L.100%), lignin-furfural 30% (L.70-F.30), lignin- furfural 60% (L.40-F.60) were used as the adhesive at three different levels ( 120 140 160gm2) accompanied with ammonium chloride (1%) as the hardener and wheat flour (30%) as the filler based on the dry weight of the adhesive. Plates made with urea formaldehyde resin at 160 g/m2 were produced as control samples. characteristics of adhesives included solid material percentage, viscosity, specific weight and PH were measured. After producing the laboratory boards, the physical and mechanical properties of samples, such as thickness swelling after 2 and 24 hours of being soaked in water, shear strength, modulus of rupture, and modulus of elasticity were measured. The results indicate that independent and interactive effects of adhesive and its consumption level on the physical and mechanical properties of plywood are not statistically significant. And in all cases, the control boards had better properties than the lignin adhesives
Ali Hasanpoor tichi; Fardad Golbabaei; Mojtaba Rezanezhad
Abstract
In this study, the possibility of making gypsum-based boards from rice straw chips with different levels was investigated. Variable factors in this study were considered in nano at three levels of 0, 3 and 7% and also the ratio of mixing rice straw to gypsum at three levels ( 5:95 , 10:90 , 15: 85 %). ...
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In this study, the possibility of making gypsum-based boards from rice straw chips with different levels was investigated. Variable factors in this study were considered in nano at three levels of 0, 3 and 7% and also the ratio of mixing rice straw to gypsum at three levels ( 5:95 , 10:90 , 15: 85 %). Thus, with the consideration of nine treatments, a total of 27 laboratory boards were constructed. The specific mass of the first target 1.10 gr/cm3 was considered. Mechanical and physical properties of composites include modulus of rupture, modulus of elasticity, internal bonding, water absorption after 2 and 24 hours of immersion, and density of boards according to standard (DIN-EN-634) and fire resistance (weight loss percentage) they were measured according to a standard ISO-11925. In order to investigate the common chapter of rice straw and gypsum as well as the distribution of nano-wollastonite, microscopic images (SEM) of the fracture surface of the samples were prepared and the results showed that the composites made with nano-wollastonite had higher mechanical and physical strengths. Microscopic imaging (SEM) showed that the boards made with 7% nano had stronger internal connections and created a uniform structure. In this study, composites made of 7% nano wollastonite with 5% rice straw were selected as the optimal treatment.
Physics and Mechanical Wood
shahrzad omrani ghahjaverstani; amir lashgari; mahran roohnia
Abstract
Non-destructive tests today play a vital role in human life. Non-destructive evaluation technology is widely used in industries, especially wood based industries and wood based products and has led to advances in Strength grading lumber, determine the disadvantages of wooden materials, Inspection of ...
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Non-destructive tests today play a vital role in human life. Non-destructive evaluation technology is widely used in industries, especially wood based industries and wood based products and has led to advances in Strength grading lumber, determine the disadvantages of wooden materials, Inspection of timber and wooden structures. The purpose of this research was to estimate the flexural strength of dynamic tests and compare them with the results of static standard tests in two Forest Pine species (Pinus sylvestris) and Rush (Fagus orientalis). The results of the comparison of the estimation of the modulus of elasticity and the estimated modulus of rupture by a non-destructive free vibration method in a free supported beam with similar results from the static test showed a very good correlation So, according to calculations done by applying a safety coefficient of 18% for beech species and 11% for pine species, a non-destructive vibration test can be substituted by a static destructive standard test for estimating the factors mentioned in these two species.
Composite wood products
Abolfazl Kargarfard
Abstract
Abstract: The application of corn stalks in the production of oriented strand board (OSB) is investigated. Corn stalks strands were produced in three sizes of 50, 75 and 100 millimeters length and dried to reach 2% moisture content. Oriented strand boards were made using either urea formaldehyde, melamine ...
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Abstract: The application of corn stalks in the production of oriented strand board (OSB) is investigated. Corn stalks strands were produced in three sizes of 50, 75 and 100 millimeters length and dried to reach 2% moisture content. Oriented strand boards were made using either urea formaldehyde, melamine formaldehyde and phenol formaldehyde resin, and two press temperatures of 175 and 185 ° C. OSB boards using poplar wood strands, 100 millimeters long were also produced as control samples. The results of strength measurements of the boards were statistically analyzed using factorial experiment and completely randomized block design. The grouping of the averages was based on Duncan Multiple Range Test. The results showed that the effect of the resin type on the flexural properties and internal bonding of the boards is statistically significant and boards produced using phenol formaldehyde resin exhibited the lowest modulus of rupture, modulus of elasticity and internal bonding strength. However, the adhesive type did not statistically influence the physical properties. The strand length also statistically influenced the board strength properties and boards made using poplar strands showed higher strength compared to corn stalks strands. The thickness swelling of the poplar OSB was almost twice the values of corn stalks OSB but the water absorption of these boards was lower than of corn stalks OSB. Press temperature adversely affected the modulus of rupture and elasticity, but higher press temperature improved the internal bonding strength. Higher press temperature increased the physical properties of the boards.
Hossein Rangavar; Behzad Bazyar; Hamed Akbari
Abstract
Abstract : In this study, the possibility of using Cicer arietinum straw residues for manufacturing three-layer particleboards was studied.The amounts of Cicer arietinum straw in mixture with industrial particles were ( % 25:75),(% 40:60),(% 55:45) respectively.Urea formaldehyde (100%) and Melamin urea ...
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Abstract : In this study, the possibility of using Cicer arietinum straw residues for manufacturing three-layer particleboards was studied.The amounts of Cicer arietinum straw in mixture with industrial particles were ( % 25:75),(% 40:60),(% 55:45) respectively.Urea formaldehyde (100%) and Melamin urea formaldehyde at different ratios of MF / UF were used as binders. The resin were applied at two levls of (% 8,10) in core and two levels of (% 10,12) in surface layers, based on oven dried weight of particles. Mechanical and physical properties of boards ( Modulus of rupture, Modulus of elasticity, Internal bonding and thickness swelling and water absorption after 2, 24 hours soaking in water) were measured and data were analyzed, statistically. The results indicated that increase of Cicer arietinum straw lead to increase of bending strength and Modulus of elasticity. Also the increase of resin content and use of Melamin urea formaldehyde resin caused to improve mechanical and physical properties. In General, the use of Cicer arietinumstraw in mixture with industrial particles up to 55% , and resin content of (10,12%) in core and surface layers, resulted in producing boards with appropriate mechanicals properties which are suitable for interior uses.
Amir Eshraghi; Habib alah Khademeslami; Amir Nourbakhsh; Behzad Bazyar; Mohammad Talaeipoor
Abstract
In this study, aspen chips with OCC (Old Corrugated Container) were used in particleboard production and samples were prepared at two different levels of resin contents (%9 and %10) and three levels of combination:
1- %25 OCC +%75 aspen, 2- %50 OCC + %50 aspen, ...
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In this study, aspen chips with OCC (Old Corrugated Container) were used in particleboard production and samples were prepared at two different levels of resin contents (%9 and %10) and three levels of combination:
1- %25 OCC +%75 aspen, 2- %50 OCC + %50 aspen, 3- %75 OCC +%25 aspen. Indeed in this study these two mentioned factors are variable and other factors such as press temperature: 165 ºC, press time: 5 minute, mat moisture %12, board density 0.75 g/cm3 and press pressure 30 kg/cm2 were constant. After the boards were manufactured according to DIN-68763 standard, were undergone different tests such as: bending strength, modulus of elasticity, internal bonding strength and thickness swelling after 2 & 24 hours immersion in water. The results indicate that second ratio(%50 OCC and %50 aspen chips) is proper for bending applications and the first ratio(%25 OCC and %75 aspen chips) is proper for tensile and thickness swelling applications. Therefore, applying the OCC more than %50 in manufacturing combination; result in decreasing the physical and mechanical properties. Moreover the results show that when the resin content increases, the board features improve.
Composite wood products
Abdolah Najafi; Mehdi Faezipoor; Habibalah Khademi eslam; Saeid Kazemi; Amir homan Hamasi
Abstract
In this study flexural properties Wood-plastic composites(WPCs), the composites made from high density polyethylene(virgin, recycled and mix of them) and four types lignocellulosic fillers (wood sawdust, sanding of MDF, particleboard sawdust and rice hull) at %60 by weight fiber loadings were manufactured ...
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In this study flexural properties Wood-plastic composites(WPCs), the composites made from high density polyethylene(virgin, recycled and mix of them) and four types lignocellulosic fillers (wood sawdust, sanding of MDF, particleboard sawdust and rice hull) at %60 by weight fiber loadings were manufactured using a dry blend/hot press method. Nominal density and dimensions of the panels were 1g/cm3 and 35Î35Î1cm, respectively. After conditioning, flexural properties of the panels including flexural modulus and flexural strength were determined. The results show the flexural modulus and strength wood plastic composites containing sanding MDF and particleboard sawdust were higher than those made from other fillers. The flexural modulus and strength were affected by kind of high density polyethylene (virgin or recycled
Composite wood products
Ahmad Jahan latibari; Habibalah Arabtabar; Fardad Golbabaei; Abolfazl Kargarfard; Amir Nourbakhsh; Abbas Fakhryan roghani
Abstract
Laminated beam ( LB.) and laminated veneer lumber ( LVL) manufactured from maple, hornbeam and beech wood is investigated. Three levels of press pressures at 30, 35, 40 kg/cm2, three levels of layer thicknesses of 2, 3, 4 mm and tangential and radial layers are investigated. Bending strength (MOR and ...
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Laminated beam ( LB.) and laminated veneer lumber ( LVL) manufactured from maple, hornbeam and beech wood is investigated. Three levels of press pressures at 30, 35, 40 kg/cm2, three levels of layer thicknesses of 2, 3, 4 mm and tangential and radial layers are investigated. Bending strength (MOR and MOE) and shear strength were measured according to ASTM 1186 and 905 respectively.The results of this investigation indicated that laminated wood strength of samples produced from hornbeam layers is superior to beech and beech is superior to maple. Statistical analysis of the results showed that the effect of wood species on strength properties is significantly different at 99% level. Press pressure also showed significant effect on strength. Increasing press pressure improved bending properties, but the highest shear strength was observed at 30 kg/cm2. Cutting direction did not influence bending strength and only influenced the shear strength. Even though the initial anticipation was the fact that thinner layer will produce stronger laminated wood. But the results or this study showed that layer thickness did not significantly affect strength properties.
