Composite wood products
Fardad Golbabaei; Kamyar Salehi; Reza Hajihassani
Abstract
In this study, the composition of bagasse composite was investigated using different amounts of bagasse particles. Bagasse and cement particles are manufactured at levels (5, 10 and 15%) and percentage of calcium chloride as cement accelerating additive at two levels (3 and 2%) based on cement dry weight. ...
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In this study, the composition of bagasse composite was investigated using different amounts of bagasse particles. Bagasse and cement particles are manufactured at levels (5, 10 and 15%) and percentage of calcium chloride as cement accelerating additive at two levels (3 and 2%) based on cement dry weight. Then, the mixture was poured into a mold measuring 15 8 18 8 8 cm and the excess water was removed from the bottom of the mold and initially weighed 10 kg on the specimens. The specimens were removed from the mold after 48 hours and kept in a glass saturated room at 90% humidity for 14 days and then finally dried in a laboratory environment. The bending strength and physical properties tests were performed on the specimens. The results showed that bagasse particles had a significant effect on bending strength and other physical properties. The bending strength was highest in boards made with 10% bagasse particles.
Composite wood products
Mehdi Kalagar; behzad baziyar; Habibalah Khademislam; Esmaeil Ghasemi; Amir homan Hemmasi
Abstract
In this paper, poly lactic acid (PLA)/ wheat straw fibers manufactured by twin screw extruder and molding compression have been studied. Wheat straw fibers were treated with trietoxymethel silane for better compatibility between two phases. Physical properties, tensile properties of the composites were ...
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In this paper, poly lactic acid (PLA)/ wheat straw fibers manufactured by twin screw extruder and molding compression have been studied. Wheat straw fibers were treated with trietoxymethel silane for better compatibility between two phases. Physical properties, tensile properties of the composites were analysis. The effect of the wheat straw fibers on the thermal properties of PLA has also been investigated in DSC experiments. The effects of silane treatment on the wheat straw fibers have been analyzed by FTIR. Scanning electron microscopy from samples surface were used for better study of water absorption and thickness swelling. Composites wheat straw fiber were treated shows signification lower water absorption and thickness swelling than composites PLA/ untreated wheat straw fibers. The lower amount of water absorption and thickness swelling occurred in the pure PLA. The existence crack and break occurred in the surface of PLA/ untreated wheat straw fibers composites after immersion in the water indicating higher water absorption and thickness swelling were in these samples. Wheat straw fibers were treated with silane due to better wetting and better linkage in the interfacial surface with PLA matrix showed higher tensile properties then PLA/ untreated wheat straw fiber composites. Differential scanning calorimeter test showed that with addition wheat straw fibers were treated to pure PLA the increased glass transition temperatures. The nucleating effect of wheat straw fibers, special treatment with silane cause to increased in the crystallization temperature composites than pure PLA which a positive effect showed on the degree of crystallization.
Amir Bagheri; Vahid reza Safdari; Amir Lashgari; Azhang Tajadini
Abstract
Ephedra shrubs are among native species of Iran and Turan habitat but their anatomical and physical characteristics have not been studied yet. In this study,physical characteristics of wood logs from three ephedra species including Mianeh Ephedra (Ephedra intermedia ),Goats Beard Ephedra (Ephedra ...
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Ephedra shrubs are among native species of Iran and Turan habitat but their anatomical and physical characteristics have not been studied yet. In this study,physical characteristics of wood logs from three ephedra species including Mianeh Ephedra (Ephedra intermedia ),Goats Beard Ephedra (Ephedra major) and Deserts Ephedra or Central Asian Ephedra (Ephedra strobilaceae Bge.) from desert areas of Yazd province were studied. Results shows that Iranian ephedra species similar to the others species show three key anatomical structures: Vessles, Theracheids and, Fibers. The presence of big pits simillar to tracheid pits in some vessel elements support the idea that they are a bridge group linking angiosperms and gymnosperms. Important anatomical features of Iranian ephedras include occurrence of clear and dendroied bodies, elongated and very hetrogenous wooden rayes and latticed vascular valves. Anatomical differences between the three ephedra species provide the key to identify them. There was not any significant difference between average physical characteristics (wet and dry density, shirinkage and swelling).Whereas, average shirinkage and swelling in radial direction was significantly higher than those in tangentiels direction.
Nazbakht Hezbi; Elyas Afra
Abstract
The present study analyzed the effect of different enzymatic treatment times using endoglucanase and refining levels to improve the properties of OCC pulp. The OCC pulps were treated by endoglucanase enzyme at a constant dosage of 1u (on o.d. pulp) at different reaction times (0.5, 1, 1.5 and 2 hours) ...
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The present study analyzed the effect of different enzymatic treatment times using endoglucanase and refining levels to improve the properties of OCC pulp. The OCC pulps were treated by endoglucanase enzyme at a constant dosage of 1u (on o.d. pulp) at different reaction times (0.5, 1, 1.5 and 2 hours) under constant process conditions. Based on the results, enzymatic treatment of OCC pulp at different time levels improved the physical and mechanical properties, compared with the control pulp, and the highest improvement level was observed at 0.5 hour reaction time. Longer enzymatic reaction time (up to 2 hours) led to a significant decrease in the physical and mechanical properties of the pulp. Evaluation of different of enzymatic treatment times and different refining levels indicated that the papers produced from endoglucanse pre-treated pulp (for 0.5 hour treatment time) showed better quality at different refining levels. However, increasing enzymatic treatment times up to 2 hours showed severe decrease both the physical and mechanical properties at higher refining levels. In general, refining enzyme pre-treated pulp and also the control pulp resulted in a higher strength property of the paper.
Asghar Taremian; Zinab Frozan; Amir Sepehr; Hadi Ghlamian; Reza Oladi
Abstract
In this study, the physical and anatomical properties of old date palm wood (Phoenix dactylifera L.) and its drying behavior was studied. Four old date palm trees grown in Bam city (Kerman provenience) were felled. Then, boards with the dimension of 300 × 50 × 30 mm were cut at DBH of trees ...
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In this study, the physical and anatomical properties of old date palm wood (Phoenix dactylifera L.) and its drying behavior was studied. Four old date palm trees grown in Bam city (Kerman provenience) were felled. Then, boards with the dimension of 300 × 50 × 30 mm were cut at DBH of trees from pith to bark. After measuring the green moisture content and specific gravity, boards were dried in a semi-industrial kiln to reach the final moisture content of 8% using a mild wood drying schedule. Cross-sectional anatomical measurements were performed on the nearest boards to the bark and pith. Results showed that the green moisture content and specific gravity of date palm wood ranged between 150-260% and 0.29–0.39 and the moisture content was increased and the specific gravity was decreased from pith to bark. Anatomical observations and statistical analysis revealed that there was no statistically significant difference between average number of vessel elements and vessel bundles between pith and bark, but the mean vessel area in pith was considerably greater than bark. Results also showed that the drying rate of date palm wood was high reaching to the final moisture content of 8% within 7 days. Drying rate of bark samples was higher than those of the pith and no deformation and surface crack was observed in the dried boards.
Mohammad amin Andalibian; Saeid Mahdavi; Hossein Kermanian; Omid Ramezani
Abstract
The possibility to improve the test liner board properties using mechanical treatments (refining) was studied. Old Corrugated Container (OCC) fibers used in a recycled paper manufacturing company were quantitatively and qualitatively analyzed and hardwood and softwood fibers content were estimated as ...
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The possibility to improve the test liner board properties using mechanical treatments (refining) was studied. Old Corrugated Container (OCC) fibers used in a recycled paper manufacturing company were quantitatively and qualitatively analyzed and hardwood and softwood fibers content were estimated as 22.6% and 60%, respectively. The mechanical treatment of pulp fiber was performed in a Valley Beater until the target freeness of 400 ml CSF. Then hand sheets with the basis weight of 127 g/m2 were made and the apparent density, Gurley air resistance, burst strength, folding endurance, Elmendorf tear strength, tensile strength and RCT were measured according to TAPPI standards. The results showed that all the properties of the refined sample increased compared to the control sample. Comparing the strength properties of the paper produced from refined pulp with the relevant values in Iranian national standards indicated the 33%, 50%, 117% increase in burst index, tensile index, and tear index, respectively. The refined pulp RCT strength increased by 28% compared to that of control sample. As the results indicated, test liner boards with suitable strength can be manufactured locally and even exported.
Mohammad hadi Aryaei monfared; Hossein Tavakoli; Hossein Hosseinkhani
Abstract
One of the lesser known local woody species of the Zirkooh-Qhaen in the east of Iran is Ammodendron persicum with the traditional name of Divdal. In this study three selected logs were used for study of wood properties. For the first time wood of this desert species was studied from different physical ...
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One of the lesser known local woody species of the Zirkooh-Qhaen in the east of Iran is Ammodendron persicum with the traditional name of Divdal. In this study three selected logs were used for study of wood properties. For the first time wood of this desert species was studied from different physical and anatomical aspects. The results showed that Ammodendron ʼs wood is a ring -porous hardwood that all parts of its cross section have long rays that is visible with naked eye. In the study of physical properties of Ammodendron̛ ҆s wood apparent density and dry one respectively was 1.125 and 0.92 g/Cm3 that put this wood to the very dense category.
Composite wood products
masoudreza habibi; Hossein Hosseinkhani; Saeed Mahdavi
Abstract
In this study, particleboard was produced using Mesquite (Prosopis juliflora) called Somr wood. Oven dry density of stem and branch wood was measured as 0.92, 0.72 g/cm3 whereas the bark weight percentage of stem and branch wood determined as 13.6 % and14 % respectively. The influence of raw material ...
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In this study, particleboard was produced using Mesquite (Prosopis juliflora) called Somr wood. Oven dry density of stem and branch wood was measured as 0.92, 0.72 g/cm3 whereas the bark weight percentage of stem and branch wood determined as 13.6 % and14 % respectively. The influence of raw material mixture (stem wood, branch wood, the blend of stem and branch wood, 50/50 w/w) and resin content 10% and 12 % (based on dry weight of the particle) on particleboard properties were investigated. Properties such as MOR, MOE, IB, thickness swelling after 2 and 24 hours immersion in water were determined according to EN standard. Except for MOE, the effect of raw material type on board properties was significant. Particleboards made from branch wood, had the highest MOR. Maximum IB was observed in boards made from the blend of stem and branch wood. With the exception of bending properties, the effect of resin content on all board properties was significant. Increasing the resin content improved board properties. The lowest value of thickness swelling after 2 and 24 hours immersion in water was obtained in particleboard made from stem wood
Mysam Abdolali sarbandi; Vahid Safdari; Sayed javad Sepidedam; Esmaeil Ganjyan
Abstract
In this research, the properties of cement fiberboard produced using different contents of nano-silica and bleached bagasse fibers were evaluated. Different ratios of bagasse fibers, cement and nano-silica were blended using an electrical blender. The mixture was then poured into a mould (15x18x18 ...
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In this research, the properties of cement fiberboard produced using different contents of nano-silica and bleached bagasse fibers were evaluated. Different ratios of bagasse fibers, cement and nano-silica were blended using an electrical blender. The mixture was then poured into a mould (15x18x18 cm dimension). The produced mould samples were matured for 14 days at room temperature and high moisture content (100%) and after maturing, the bending strength and physical properties of boards were measured. Results showed that both materials (naosilica and bagasse fibers) changed the bending and physical properties of the final boards. The bending strength of samples increased with the increase in nano-silica up to 1% and exceeding 1% decreased this property. It is because high content of silica (more than 1%) results in aggregate of nano-silica and cement and micro cracks occurred in samples. Also the increase in bagasse fiber up to 4% increased of bending strength of boards and more bagasse fibers decreased the bending strength. It is because high bagasse fibers cannot distribute in the cement matrix and fiber bundles reduced the bending strength. However, as the nano-silica and bagasse fibers content increase, the water and moisture absorption as well as thickness swelling increases, whereas density decreases.
Composite wood products
Hamid Hatefnia; Aliakbar Enayati; Kazem Dosthosseini; Mohammad Azadfalah
Abstract
In this research the effect of steam pretreatment on the physical and mechanical properties of particleboard were evaluated. Steam pre-treatment was applied on the particles of poplar wood in a stainless steel reactor at four different temperature (155, 165, ...
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In this research the effect of steam pretreatment on the physical and mechanical properties of particleboard were evaluated. Steam pre-treatment was applied on the particles of poplar wood in a stainless steel reactor at four different temperature (155, 165, 175 and 185 ◦C) and three different retention time (15, 30 and 45 min). The obtained results indicated that mechanical properties include MOR and IB content of the particleboard decreased, whereas MOE increased initially then decreased with severity of treatment conditions. The physical properties of the board i.e. thickness swelling, water absorption and consequently dimensional stability were improved by steam pretreatment. The observed changes can be attributed to reduction in hemicelluloses content and hydroxyl groups within wood component.
Pulp and paper
Babak Mirzaei; Kazem Dos hosseini; Esmaeil Ghasemi; Yahya Hamzeh
Abstract
In this study two types of paper sludge, prepared by Mazandaran wood and paper company and Latif papermaking company along with wood flour utilized as plastic filler in polypropylene and high density polyethylene based composites. Weight percentage ratio of coupling agent, polymer and filler were kept ...
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In this study two types of paper sludge, prepared by Mazandaran wood and paper company and Latif papermaking company along with wood flour utilized as plastic filler in polypropylene and high density polyethylene based composites. Weight percentage ratio of coupling agent, polymer and filler were kept constant 2%, 38%, and 60% in all formulations, respectively and composites were prepared by varied ratios of paper sludge and wood flour include 0: 60, 40: 20, 20: 40, and 60:0. Density, water absorption and thickness swelling of injection molded composites then measured. The results indicated the gradual substitution of wood flour by paper sludge increases the density of composites, and improves their water absorption and thickness swelling. The ratio of paper sludge to wood flour had statistically significant difference on all these properties, but the paper sludge type showed statistical difference just on the density of composites. Further to that, polypropylene based composites demonstrated lower density, water absorption and thickness swelling compared to high density polyethylene based ones.
Pulp and paper
Ali Solimani; Hossein Resalati; Eiman Akbarpoor
Abstract
In this research, effects of mixing the birch wood with hornbeam and beach on optical and physical properties of papers produced at constant freeness range of 300 ml, CSF and yield of 85% and reference of CMP pulp (75% hornbeam plus to 25% beach) was investigated. CMP pulp was produced from birch ...
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In this research, effects of mixing the birch wood with hornbeam and beach on optical and physical properties of papers produced at constant freeness range of 300 ml, CSF and yield of 85% and reference of CMP pulp (75% hornbeam plus to 25% beach) was investigated. CMP pulp was produced from birch chips at 10,20,30 and 40% content within the conditions of pulp yield:85%, liquor to dried chip ratio (L/W) of 7/1, sulfite percent of 20% on oven-dried wood chips, cooking temperature:1600C, cooking time:85-135 minutes blended with 60-90 % hornbeam and beach. After defibration and refining the cooked wood chips, the standard hand sheets of 60 g/m2 were made from different pulps and the optical and physical properties of paper produced were compared. The results from comparing the optical properties of paper showed that using up to 40% birch chips blended with hornbeam and beach led to brightness improvement and yellowness and opacity reduction compared to control CMP pulp. Increase of birch use to 30% indicated no significant effect on opacity values at confidence level of 99% compared to control CMP pulp. Utilizing 40% birch resulted in the preparation of papers with lower caliper, smoother surface and higher air resistance.
Iman Akbarpoor; Hossein Resalati; Ahmad reza Saraeian
Abstract
In this study, deinking of waste newspaper was investigated by conventional and enzymatic methods. Conventional deinking was done in pulping times of 10, 20 and 30 minutes along with different processes of washing, flotation and combined washing/ flotation. Enzymatic deinking was accomplished ...
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In this study, deinking of waste newspaper was investigated by conventional and enzymatic methods. Conventional deinking was done in pulping times of 10, 20 and 30 minutes along with different processes of washing, flotation and combined washing/ flotation. Enzymatic deinking was accomplished at different charges of 0.025, 0.05, 0.1 and 0.2% cellulase enzyme (based on oven-dried waste paper), pulping times of 10,15 and 20 minutes, pH range of 5-5.5 along with one-stage washing process. Optimum compositions were selected from chemical and enzymatic treatments and then physical and mechanical properties of the paper produced in optimum conditions were compared. Achieved results from comparison of the physical properties of optimum chemical and enzymatic treatments showed that, the paper produced from deinked pulp by conventional method had higher calliper, bulk and porosity. Using of 0.1% cellulase resulted the papers with higher tensile and breaking length compared to chemical treatments. The papers could be produced with similar burst and tear indexes compared to chemical treatments using of 0.1% cellulose, as well.
