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 ...
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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.
Mir Reza Mousavi; Asghar Tabei; Mostafa Madanipour; Mohammad Farsi
Abstract
In this study, the effect of walnut shell and charcoal flour on the applied characteristics of the resulting plastic composites was investigated. For this purpose, walnut shell and charcoal flour in three levels of 20, 30 and 40% were mixed with high density polyethylene using Brabender internal mixer ...
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In this study, the effect of walnut shell and charcoal flour on the applied characteristics of the resulting plastic composites was investigated. For this purpose, walnut shell and charcoal flour in three levels of 20, 30 and 40% were mixed with high density polyethylene using Brabender internal mixer during the melt mixing process, then standard test samples were made by injection molding method. Mechanical properties including tensile and flexural strength, tensile and flexural modulus and impact strength were measured. Physical properties including water absorption and thickness swelling after 24 hours immersion were evaluated and scanning electron microscopy images were also examined. The results showed that the flexural strength and impact strength of the wood plastic composite containing 40% walnut shell flour were higher than the samples containing 40% charcoal flour. Also, by increasing the walnut shell and charcoal flour from 20 to 30%, the flexural strength increased by 3.3% and 6.1%, respectively, and by increasing the walnut shell and charcoal flour from 20 to 40%, the flexural modulus increased by 51.9% and 63.8%, respectively. Other results of mechanical strength indicate that with increasing walnut shell charcoal from 20 to 40%, tensile strength and modulus increased to 22.9 and 109.7%, respectively, and with increasing walnut shell and charcoal flour from 20 to 40%, the impact strength decreased by 6.6 and 5.4%, respectively. The results of physical properties showed that with increasing walnut shell and charcoal flour from 20 to 40%, water absorption for 24 hours decreased by 19.2 and 8.4%, respectively, and thickness swelling by 24 hours decreased by 53.6 and 46.7%, respectively.
Fardad Golbabaei; Reza Hajihassani; Kamyar Salehi; Asghar Tabei
Abstract
The aim of this study was to construct lightweight structures and reduce energy loss. The aim of this study was to produce cement wood or composite products by combining organic particles such as wood fibers and lignocellulosic materials with monolith. The investigated product consisted of cement wood ...
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The aim of this study was to construct lightweight structures and reduce energy loss. The aim of this study was to produce cement wood or composite products by combining organic particles such as wood fibers and lignocellulosic materials with monolith. The investigated product consisted of cement wood made from scrap wood fibers and poplar wood particle thickness of 20 mm on both sides of the structure and 10 mm thick unolith in the middle of the structure. Products manufactured by Unolite Cement will have a combination of cement and Unolite properties. In this study, according to the studied variables including lignocellulosic materials and amount of additive (such as calcium chloride (Cacl) at two levels of 3 and 5%, the best specimens were prepared using 10% lignocellulosic materials. The thickness of the specimens was uniform at the two monolithic surfaces and all fabrication conditions such as discharge rate, press pressure, coalescence rate were assumed to be uniform and constant.In static bending experiment the mean maximum load force for ordinary brick failure was 3933.26N and the mean. The maximum load for breaking the cement stick was 389/78 N, which was approximately It has 10% resistance to ordinary brick but ordinary brick breaks abruptly when fractured, while the monolithic brick is gradually broken and the insulation properties due to the cellulosic fibers and the monolith in it are higher than the ordinary brick due to its low resistance to use. Recommended in partitions.
Mona Otarod; Asghar Tabei
Abstract
This study was conducted to determine morphological characteristics and chemical components of sunflower stalks (Helianthus annus. Var, cheernianka 66) cultivated in Astara area. After collecting number of stalks, 6 stalks of the same size were selected to determine for morphological characteristics ...
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This study was conducted to determine morphological characteristics and chemical components of sunflower stalks (Helianthus annus. Var, cheernianka 66) cultivated in Astara area. After collecting number of stalks, 6 stalks of the same size were selected to determine for morphological characteristics and remaining stalks were used to determine the chemical components. Morphological tests were performed to determine fibers dimensions and biometric coefficients by sampling from 3 heights of stalks (5%, 50% and 75%).Maceration of fibers was done by Franklin method . Measurement of chemical components was performed on the basis of TAPPI standard in 2 modes such with bark and without bark. The total average of fiber length, fiber diameter, lumen diameter and fiber wall thickness were measured for this stalk as 663µm , 29.848 µm, 25.182 µm and 2.336 µm respectively. The total average of slenderness coefficient, flexibility coefficient and Runkel index of fibers were calculated as 22.681, 84.259 and 0.188 respectively. Average percentage of cellulose, lignin, acetone extractives, alcohol extractives, hot water extractives and ash for this stalk were measured as 40.066, 22.758, 3.953, 1.86, 2.186 and 3.208, respectively. The results showed that fibers length increased with increasing of stalk height, but this increasing was not significant. Fibers diameter, lumen diameter and fibers wall thickness decreased with increasing of stalk height, this decreasing was significant for fibers diameter and lumen diameter in the height of 75%, but it was not significant for fibers wall thickness. Also, the results showed that bark has significant effect on all of the chemical components, so that, the stalk with bark has lower cellulose and more lignin, extractives and ash in compare with the stalk without bark.
Chemistry of wood
Asghar Tabei
Abstract
In this study, changes in optical behavior of Poplar Kraft lignin before and after methylation by using dimethyl sulphate, was monitored by measuring optical indices ( brightness,light absorbtion coefficient, light scattering coefficient,light absorbtion coefficient to light scattering coefficient ratio ...
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In this study, changes in optical behavior of Poplar Kraft lignin before and after methylation by using dimethyl sulphate, was monitored by measuring optical indices ( brightness,light absorbtion coefficient, light scattering coefficient,light absorbtion coefficient to light scattering coefficient ratio and Post-Color numbers) of impregnated papers following accelerated photo aging. The structural changes in lignin caused by methylation reaction, were verified by using fourier transform infar red( FT-IR) spectroscopy. The results showed that, by methylation of lignin, it was observed that, in methylated lignin-containing papers, the extent and stability of brightness is more and post- color number is less compared to control samples. In methylated samples, even the strange phenomenon of photo bleaching was observed. Therefore, it was found that, methylation of lignin can prevent the formation of quinone groups and increases the stability of the optical indices in the photo aging conditions.Keywords: Kraft lignin, methylation treatment, accelerated photo- aging, optical indices,lignin-containing papers.
Chemical conversion
Seyyed Pedram Hashemi Beygzadmahalleh; Seyyed Peyman Hashemi Beygzadmahalleh; Asghar Tabei
Abstract
This study has been conducted to determine morphological characteristics of fibers and amount of chemical components of grapevine branches cultivated in Astara in province of Guilan. For this purpose the number of 53 branches, with same size and diameter, were cut from some grapevine and sent to laboratory ...
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This study has been conducted to determine morphological characteristics of fibers and amount of chemical components of grapevine branches cultivated in Astara in province of Guilan. For this purpose the number of 53 branches, with same size and diameter, were cut from some grapevine and sent to laboratory of wood and paper industries in Islamic Azad university Astara branch. To separate the fibers and for studying their morphological characteristics, wooden chip sampling from the branches was conducted at 3 heights of them (5%, 50% and 75%). Fiber separation was done by method (Franklin 1954) and then dimensions of fibers and their biometric coefficients were determined. From a number of separated branches, wood flour was prepared in two modes of with skin and without skin and then, percentage of chemical components of them was determined according to TAPPI standard. The overall average percentage of holocellulose, alpha cellulose, hemi cellulose, cellulose, lignin, acetone extractives, alcohol extractives, hot water extractives, cold water extractives and ash were measured as 87.59, 56.99, 30.59, 47.20, 25.16, 5.90, 2.53, 4.41, 1.79 and 1.79 percent, respectively. Also, the total average of fiber length, fiber diameter, lumen diameter and cell wall thickness were measured as 0.96 mm, 26.45 µm, 15.48 µm and 5.49 µm, respectively. Also, the total average of slenderness, flexibility and runkel coefficients were calculated as 36.29, 58.50 and 0.71, respectively. The results showed that, in the debarked branches of grapevine trees, the amounts of holocellulose, alpha cellulose, hemi cellulose and cellulose are more than with skin branches and debarked branches have less lignin, extractives and ash than with skin branches. Also. The results showed that dimensions of the fibers including fiber length, fiber diameter and fiber lumen diameter, except cell wall thickness, decreased with increasing of height.
Pulp and paper
Seyed_Pedram Hashemi; Asghar Tabei; Seyyed Peyman Hashemi
Abstract
In this study the effect of different values of peroxide in three levels 3%, 4%, 5% and sodium hydroxide in two levels 2%, 3%, on bleaching of tobacco stalks ( Nicotiana tabacum L. 'PVH 19') soda pulp was investigated. Tobacco stalks were soda pulped using 22% alkali in 170°C for 100 minutes. Produced ...
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In this study the effect of different values of peroxide in three levels 3%, 4%, 5% and sodium hydroxide in two levels 2%, 3%, on bleaching of tobacco stalks ( Nicotiana tabacum L. 'PVH 19') soda pulp was investigated. Tobacco stalks were soda pulped using 22% alkali in 170°C for 100 minutes. Produced pulp had 37.1 % yield and kappa number 62. Bleaching process included two stages: chelating and alkali peroxide bleaching. Results indicated that brightness increased and kappa number decreased by increasing sodium hydroxide and peroxide Hydrogen level.The data related to 3% caustic soda and 5% peroxide treatment without chelating stage, indicated that initial chelating stage significantly affected on the brightness, kappa number and yield of the bleached pulp, and this treatment had the lowest brightness and the highest kappa number and yield among all treatments. Finally, 3% caustic soda-5% peroxide treatment with initial chelating stage had the highest brightness (44.50%) and the lowest yield (83.20%), was selected as the best treatment.
Pulp and paper
Seyyed Peyman Hashemi Beygzadmahalleh; Seyyed Pedram Hashemi Beygzadmahalleh; Asghar Tabei
Abstract
Tobacco (Nicotianan tabacum) and an old industrial plant in the north, Iran to supply tobacco leaf to produce significant amounts of stem tobacco cultivation and the annual production is in the north of the country. In this research stems of tobacco variety Coker 347 randomly Gilan district, city of ...
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Tobacco (Nicotianan tabacum) and an old industrial plant in the north, Iran to supply tobacco leaf to produce significant amounts of stem tobacco cultivation and the annual production is in the north of the country. In this research stems of tobacco variety Coker 347 randomly Gilan district, city of Astara was prepared according to the TAPPI standard test, wood flour were prepared and extractives were determined. The results showed that the mean shoot extractive tobacco varieties Coker 347 (10.41 percent). The extractive solvent toluene - ethanol volume ratio (2 : 1) of milled wood was extracted. Extractive made into a glass vial and transferred to the BSTFA reagent was added. Samples for one hour at room temperature and 70 ° C water bath and then by (GC / MS) were analyzed. Atotal of 11 chemical compounds in tobacco stem wood extractives variety Coker 347 were identified with different percentages of tobacco stem wood Coker 347 varieties exist. These compounds include, P- Prydyn , 1 – tri methyl Saylyl , 1,2 - benzene di- carboxyl acid , alpha - D - Golokopyranoz , 11, 8 – di methyl - 13 - (4 - aksu -1 - methyl ) , tri Floyver methyl isopropyl sulfide are the highest values.
Asghar Tabei; Reza Solhnejad; Arash Farajpoor Roodsari
Abstract
This study lignin from unbleached hardwoods chemimechanical pulp was extracted and the chromophor functional groups of the lignin were studied. Acetylation and reduction treatments were perfomed and samples were analyzed by FT-IR spectroscopy. A mild acidic dioxin extraction method was employed to isolate ...
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This study lignin from unbleached hardwoods chemimechanical pulp was extracted and the chromophor functional groups of the lignin were studied. Acetylation and reduction treatments were perfomed and samples were analyzed by FT-IR spectroscopy. A mild acidic dioxin extraction method was employed to isolate lignin. For the acetylation and reduction treatments of lignin acetic acid and sodium borohydride were used respectively. The results of untreated and treated (acetylated and reduced) lignin spectra showed that, the major of lignin chromophor groups such as hydroxyl and carbonyl groups have been reduced or eliminated by these treatments. In the acetylated lignin, the absorption band of hydroxyl groups has been weakened and in the 1743.16 Cm-1 region, acetoxy compounds band has appeared and also a cluster absorption band was observed in the 1228.76 Cm-1 region. In the reduced lignin, most of the absorption bands of the carbonyl groups have been weakened or eliminated, especially in the 1705.56 and 1629.54 Cm-1 region.
Composite wood products
Asghar Tabei; Arash Farajpoor Roodsari
Abstract
In this study, effects of the flour of cellulosic shell of Pistachio and nanoclay loading on the physical and mechanical properties of wood plastic composite were investigated. Hence, flour of cellulosic shell of Pistachio, in levels of 30, 40 and 50 and Nano clay of cloisite 15A in three levels (0, ...
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In this study, effects of the flour of cellulosic shell of Pistachio and nanoclay loading on the physical and mechanical properties of wood plastic composite were investigated. Hence, flour of cellulosic shell of Pistachio, in levels of 30, 40 and 50 and Nano clay of cloisite 15A in three levels (0, 3 and 5%) was mixed with Corn starch polymer. Samples were made with a laboratory twin-screw extruder and then injection molding. The heating temperature profile and rotational speed of the screws were set at 180–170–160–160 oC and 60 rpm, respectively. Mechanical properties including tensile and flexural properties as well as notched impact strength and physical properties including water absorption and thickness swelling were measured. The results showed that flexural and tensile strength, water absorption of the samples increased as the flour content increased from 30 to 50% (w/w), but tensile modulus, notched impact resistance and thickness swelling decreased. Furthermore, tensile modulus increased as the Nannoclay content increased from 0 to 5% (w/w). Besides, Flexural and tensile strength, Flexural modulus, notched impact resistance increased as Nannoclay content increased from 0 to 3% (w/w). beyond this limit (to 5% (w/w)), they decreased.Water absorption and thickness swelling of the samples decreased as the Nannoclay content increased from 0 to 5% (w/w).
Tahereh gholizadeh; Arash Farajpour Roudsari; Asghar Tabei
Abstract
The purpose of this study was to compare the chemical compositions and biometric features of stem and cone fibers (length, diameter, and wall thickness) and the derived coefficients of loblolly pine (Pinus taeda) in Astara district, Gilan province. Discs from stem and cone were randomly taken and the ...
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The purpose of this study was to compare the chemical compositions and biometric features of stem and cone fibers (length, diameter, and wall thickness) and the derived coefficients of loblolly pine (Pinus taeda) in Astara district, Gilan province. Discs from stem and cone were randomly taken and the chemical compositions and biometric features were measured employing the TAPPI standard test methods andFranklinmacerating technique, respectively. The biometric coefficients were estimated as well. Statistical analyses of the results indicated that the average cellulose content in stem and the cone was 54.83% and 27.57%, respectively. Lignin was estimated to be 32.57% in the stem and 34% in the cone. Furthermore, extractives soluble in ethanol, acetone and water from stem wood were measured as 92%, 1.97% and 7.04% respectively. The relevant values for pine cone were 1%, 2.45% and 7.28%, respectively. According to the results of statistical analysis, there was 5% significant difference between the results measured from cones and the stem except for the slenderness ratio. Regarding the length, diameter, lumen diameter and flexibility factor, the P. taeda stem possesses a higher value compared with cone and the runkel ratio was higher in cones compared to stem.
Iraj Shiyarkar; Asghar Tabei; Arash Farajpoor Roodsari
Abstract
This study was conducted to determine and compare the morphological characteristics and chemical components of Corn stalks (Zea mays: 704 & Oilseed varieties) cultivated in Astara area. Samples were prepared from both varieties, a part of stalks were selected for chemical components determination ...
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This study was conducted to determine and compare the morphological characteristics and chemical components of Corn stalks (Zea mays: 704 & Oilseed varieties) cultivated in Astara area. Samples were prepared from both varieties, a part of stalks were selected for chemical components determination and the rest was used to examine the morphological features. The average of fiber length, fiber diameter, lumen diameter and fiber wall thickness for oilseed variety and 704 variety were measured as0.859 mm, 23.63 µm, 16.62 µm ,3.51 µm and0.727 mm, 18.77 µm, 11.39 µm and 3.7 µm respectively. The average percentage of cellulose, lignin, acetone extractives, alcohol extractives, hot water extractives and ash for oilseed variety was measured as 36.99, 20.5, 13.85, 2.02, 7.53 and 6.71, respectively. The relevant values for 704 varieties were 34.33, 17.5, 12.35, 1.35, 6.30 and 5.55 percent. Fiber dimensions and biometric coefficients between nodes and internodes, and between the varieties were compared and the results showed that there were significant differences between fiber length, fiber diameter, fiber lumen and biometric coefficients. The fiber dimensions and biometric coefficients between nodes and at the internododal sections of both varieties are compared and there was significant difference between all variables. The comparison of chemical components between stalk with and without bark for each variety showed that there were significant differences between the content of cellulose, lignin, hot water extractives and ash. However, there was no significant difference between lignin from 704 varieties. In comparison of chemical components between two varieties in stalk with bark, there were significant differences between the content of cellulose, lignin, acetone extractives, hot water extractives and ash; whereas in the case of stalk without bark, these differences were significant only for the acetone extractives, hot water extractives and ash.
Shima Ramezani; Mohammad Talaeipoor; Misam Aliabadi; Asghar Tabeai; Behzad Bazyar
Abstract
Samples were prepared from the native poplar species (Populus alba) grown in Mehnan, a region in Bojnourd at the ages 5 and 25 and the anatomical, biometrical and chemical characteristics of the samples sections in three directions (cross section, radial and tangential) of the tree were measured. ...
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Samples were prepared from the native poplar species (Populus alba) grown in Mehnan, a region in Bojnourd at the ages 5 and 25 and the anatomical, biometrical and chemical characteristics of the samples sections in three directions (cross section, radial and tangential) of the tree were measured. Dioxan and Klason lignin were measured. Structural similarities in vascular cavities or impacted vessels in the form of binary, tripple or tetraploidy groups in juvenile and mature wood was observed primarily in radial direction. Fiber length and cell wall thickness variation in the juvenile and mature wood was significantly different and as the age of the tree increases, such difference is more significant. This point need to be considered by cellulose industries. As the age of the tree increase and the wood matures, significant change in vessel size in samples from 5 or 25 years old trees was not detected. The result showed that the older wood contains lower content of extractive and lignin and higher content of cellulose
Vahid Safdari; Seyyed Peyman Hashemi Beygzadmahalleh; Asghar Tabei; Seyyed Khalil Hosseinihashemi
Abstract
Tobacco (Nicotiana tabacum) is one of the non-wood species and its stalks are the main crop after harvesting which can be used in composite board and paper industry. For better use of this non-wood fibrous raw material, the evaluation of anatomical, morphological and chemical components are necessary. ...
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Tobacco (Nicotiana tabacum) is one of the non-wood species and its stalks are the main crop after harvesting which can be used in composite board and paper industry. For better use of this non-wood fibrous raw material, the evaluation of anatomical, morphological and chemical components are necessary. Tobacco stalks "Coker"cultivar 347 which is widely planted in Gilan province of Iran were randomly sampled. Anatomical properties (cross, tangential and radial sections) and morphological properties (fiber length, fiber diameter, and cell wall thickness) were measured and the indices and ratio of the fibers including: slenderness index, runkel index, flexibility ratio in three heights of stem (5%, 50% and 75%) were calculated. The Chemical components including: Cellulose, lignin, ash, alpha cellulose and hemicellulose of stem with bark and without bark were recorded according to related standards and the results were ststistically analyzed. Results showed that the chemical components of the tobacco stalk were desirable but the index of L/D of fibers were lower than many non-woods and hardwoods. Therefore, it is assumed that the paper produced from tobacco stalks do have suitable tear strength. The runkel index (2 cell wall thickness / fiber diameter) is close to hardwoods and many non-woods, Therefore, it is presumed that paper have appropriate tensile, burst and folding strength. It is predicted that tobacco stalks combined with softwoods with long fibers can produce good quality paper.
