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.
Ai Hasanpoor tichi; Fardad Golbabaei; Habibollah Khademi Eslam
Abstract
In this study, the effect of nano-wollastonite on physical, mechanical and morphological properties of composites made of bagasse and gypsum was investigated. The mixing ratio of sugarcane to gypsum pulp at three levels (80:20, 70: 30 and 40: 60%) and nano-wollastonite at three levels of zero, 3 and ...
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In this study, the effect of nano-wollastonite on physical, mechanical and morphological properties of composites made of bagasse and gypsum was investigated. The mixing ratio of sugarcane to gypsum pulp at three levels (80:20, 70: 30 and 40: 60%) and nano-wollastonite at three levels of zero, 3 and 7% were considered as the variables of this study. The thickness of the test boards was 16 mm cake density of all boards was considered to be 1.10 gr/cm3. Then the mechanical and physical properties of the specimens including modulus of rupture, modulus of elasticity, internal bonding, water absorption after 2 and 24 hours immersion and density of boards according to DIN-EN-634 and fire resistance (weight loss percentage) according to ISO 11925 Were measured. In this study, a thermocouple and a flask were used to measure the hydration heat. Microscopic images (SEM) were obtained from the fracture surface of the specimens to investigate the common boundary between bagasse-gypsum and nano-dispersion. The results showed that with increasing bagasse mixing, the modulus of rupture, modulus of elasticity and internal bonding decreased and water absorption and weight loss percentage of boards exposed to fire increased. Application of nano-wollastonite up to 7% improved all mechanical and physical properties of composites. Also, microscopic imaging (SEM) showed that the optimum level of nano-wollastonite can fill vacant voids due to gypsum hydration and create a uniform structure.
Composite wood products
Hossein Rangavar; Amir Nourbakhsh; Saeid Haji hatmlo
Abstract
The effects of nano-wollastonite on physical and mechanical properties of wood plastic composites made with dried sunflower stalks and alder wood flour, were studied. Five levels of sunflower stalk flour in ratio of the mass wood dry flour containing 0, 25, 50, 75 and 100 percent and nano-wollastonite ...
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The effects of nano-wollastonite on physical and mechanical properties of wood plastic composites made with dried sunflower stalks and alder wood flour, were studied. Five levels of sunflower stalk flour in ratio of the mass wood dry flour containing 0, 25, 50, 75 and 100 percent and nano-wollastonite Powder in three levels, 3, and 5% were considered as variables of the study. Physical and mechanical properties, perpendicular to the screw strength, bending strength, modulus of elasticity, water absorption and thickness swelling after 2 and 24 soaking hours in water were measured in accordance with the standard DIN- EN. In order to examine the intersection of wood and polymer as well as distribution patterns of nanoparticles in the polymer matrix microscopic photos were taken. The results showed that by increasing of sunflower stalk flour in the mixing with wood flour up to 25% increased resistance to screw withdrawal and up to 50 percent increase in flexural strength and modulus of elasticity of wood-plastic composites, respectively. Sunflower stalk flour mixed with alder wood flour increased water absorption and thickness swelling after 2 and 24 hours immersion in water. The use of nano-wollastonite up 5% in relation to the total mass of all the boards improved the physical and mechanical properties of wood-polymer composite.
Azar Haghighi; Hamid reza Taghiyari; Ali nagi Karimi
Abstract
In the present study, fire-retardant properties of nano-wollastonite in fir wood (Abies alba) was studied. Water absorption and volume swelling of the specimens were also measured. Specimens were prepared according to ISO 11925 standard specifications to measure the fire-retarding properties, and ASTM ...
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In the present study, fire-retardant properties of nano-wollastonite in fir wood (Abies alba) was studied. Water absorption and volume swelling of the specimens were also measured. Specimens were prepared according to ISO 11925 standard specifications to measure the fire-retarding properties, and ASTM D4446 -2002 standard to measure physical properties. Impregnation of wood specimens with nano-wollastonite was carried out at four consumption levels of 4, 6/3, 10 and 12%, using Bethel method (full-cell process).Five fire-retarding properties were measured; weight loss (%), ignition point (s), duration of flame after removing the burner (s), duration of glow after removing the burner (s),and carbonization area (%). The results showed that fire-retarding properties increased with the NW-content. Furthermore, the treated wood specimens showed higher dimensional stability.
