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 ...
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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.
Mechanical conversion of wood and wooden fittings
Mostafa Poozesh; Hamid Reza Mansouri; babak Nosrati; Alireza Samzadeh
Abstract
This objective of this investigation was to modify and improve the water resistance of urea formaldehyde (UF) bonded particleboard adding Boric acid to the resin. Four levels (1, 2, 3 and 4) of boric acid based on the dry weight of the bonder were added to the UF resin. Then these mixtures were ...
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This objective of this investigation was to modify and improve the water resistance of urea formaldehyde (UF) bonded particleboard adding Boric acid to the resin. Four levels (1, 2, 3 and 4) of boric acid based on the dry weight of the bonder were added to the UF resin. Then these mixtures were used to produce particleboard. Physical and mechanical properties were examined according to the ASTM, D1013-04. The results showed that the using of this additive increased the water absorption and thickness swelling resistance after 2 and 24 hours immersion in water. Also using this additive increased the internal bonding of the boards after 24 hours after immersion in water, compared to the control sample but in the case of dry samples, the internal bonding decreased compared to the control sample. However it was not lower than standard value. As the Boric acid levels increased to 2 percent, bending strength of the samples was increased compare to the control sample and after this level it was decreased. Also with increasing the levels to 4 percent, modulus of elasticity of boards were increased compare to the control sample
Physics and anatomy
Babak Nosrati; mohamad haghpanah; masih masoudifar; alireza dorostkar
Abstract
In this research microscopic properties of wood near the pith to bark in Dalbergia sissoo was investigated. For this reason 3 stands of 10 years old Dalbergia sissoo trees from ShoshDanial area in Khozestan province were selected and cut. For measuring fiber biometrics of samples, from each trees one ...
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In this research microscopic properties of wood near the pith to bark in Dalbergia sissoo was investigated. For this reason 3 stands of 10 years old Dalbergia sissoo trees from ShoshDanial area in Khozestan province were selected and cut. For measuring fiber biometrics of samples, from each trees one disc and from each disc 10 pell in match's size segregated and tested. Segregation of fibers was done with Franklin method. Also microscopic segments of wood near the pith and bark were studied with light microscope. The results showed that the length, total and lumen diameter, and thickness of cell wall are significantly different and this values were increased from pith to bark. Ray widths and vessel diameters in wood near the pith and bark were 36.15, 132.98 and 31.82, 98.26 µm respectively and showed a significant difference in the level of 5%. The average number of vessels and the number of rays in wood near the pith and bark were 3.46, 7.20 and 3.54, 6.68 number respectively. Also ray length means in wood near the pith and bark were 130.86 and 132.05µm respectively and didn’t show a significant difference in the level of 5%.
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.