Mohammad Mehdi Brazandeh; Hossein Hosseinkhani; Saeid Eshagi; Abas Fakhryan
Abstract
Abstract Regarding undesired effects of formaldehyde on the health of people and enviroment, it is desired to evaluate the amount of emission of this gas from a wood composite product in order to introduce a practical method for evaluating the amount of it,s emission from any other wood product. To do ...
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Abstract Regarding undesired effects of formaldehyde on the health of people and enviroment, it is desired to evaluate the amount of emission of this gas from a wood composite product in order to introduce a practical method for evaluating the amount of it,s emission from any other wood product. To do this, particleboards of Haloxyon persicum were prepared in three different moisture levels using urea-formaldehyde adhesive. Formaldehyde emissions were evaluated as p.p.m using desciccator method ASTM D 5582-00.The results show that formaldehyde emission is reduced by raising moisture gradient such as emission values were determined as 8.946 ppm, 6.312 ppm and 4.172 ppm for the particleboards with moisture gradients of 0, 2 and 4 percent, respectively. Increasing moisture gradient from 0 to 2 percent resulted in 29 percent and increasing moisture gradient from 2 to 4 percent resulted in 34 percent less formaldehyde emissions, respectively. In addition, comparison these amounts with standard values show that these particleboards should be only used in the outdoors and not be used in the indoors at any way.
Azhang Tajdini; Amir hossein Taghadosi; Shadman Pourmousa; Ahmad Jahan-Latibari; Vahid reza Safdari
Abstract
Abstract: In the recent years due to the innovations taking place in the production, packaging and shipping of furniture, world trade of these products has grown substantially. This issue along with some outstanding problems in manufacturing and marketing various kinds of wooden has caused that furniture ...
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Abstract: In the recent years due to the innovations taking place in the production, packaging and shipping of furniture, world trade of these products has grown substantially. This issue along with some outstanding problems in manufacturing and marketing various kinds of wooden has caused that furniture imports to Iran has enjoyed significant growth .In order to achieve the efficient and economic import, identify all factors that the perspective of experts led to prefer these products in compared with similar domestic production will be essential, therefore in this research in order to investigate the reasons for the expansion of the import quantities, the standardized questionnaires (certified by professionals and academic professors in four groups: Economics, Environment, Technical and Technological, and Consumption) are provided by use of documentary and survey research methods to investigate the effective indices on importing wooden furniture to Iran in order to describe the reasons of its widespread throughout Iranian experts. These main indexes indices of imports are rated by three methods: Likert spectrum, Duncan Test, and relative importance ratio of each index. We applied Likert spectrum on the whole statistical population and it shows that Environment index holds the first rank and Consumption, Technical and Technological, and Economics indexes are followed respectively. Duncan test shows Economics index has the first rank, Environment index holds the second place. Technical and Technological index are in the same place as Consumption index and according to the test there is no meaningful differences between them. On the other hand, using the relative importance ratio method we classified related occupations into 4 groups: producers, vendors/ distributers, importers, and consumers. We employed third method to see how these four groups evaluate the importance of each index. Results are as follows: PRODUCERS believe that Environment index is in the first place and then Economics, Technical and Technological, and finally Consumption index. VENDORS/DISTRIBUTORS believe Consumption, Technical and Technological, Economics, and Environment index is the sequence. IMPORTERS believe that Consumption index is in the main priority and then Technical and Technological, Economics, and Environment hold next places.
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.
Mostafa Kohantorabi; Mehran Rohnia
Abstract
In this study, detect of damage in scarf joint and finger joint using the variations in dynamic shear modulus values and Correlation Coefficient factor of the beech wood specimens was investigated. Numbers of 42 Samples were selected according to ISO 3129 international standard. ...
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In this study, detect of damage in scarf joint and finger joint using the variations in dynamic shear modulus values and Correlation Coefficient factor of the beech wood specimens was investigated. Numbers of 42 Samples were selected according to ISO 3129 international standard. The Scarf and finger joints created with three different glue coverage rates in samples and then flexural vibration tests in free-free beam were performed. The results showed that defects changed the dynamic shear modulus values in both joints, however it is not possible to realize the amount of defects from these variations. Whereas, the changes in Correlation Coefficient factor were useful to detect the amount of defects in both joints.
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.
ُSima Sepahvand; Saeid Ziaee Khosro Shahi; Tagi Tabarsa
Abstract
This study provides an investigation of particleboard manufacture using tannin-ureaformaldehyde adhesive. Test board samples were made with regard to various replacementpercentage of tannin–urea (levels of 0, 10, 20 and 30%) and press time (12 and 15 min) andtheir properties were determined. Achieved ...
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This study provides an investigation of particleboard manufacture using tannin-ureaformaldehyde adhesive. Test board samples were made with regard to various replacementpercentage of tannin–urea (levels of 0, 10, 20 and 30%) and press time (12 and 15 min) andtheir properties were determined. Achieved data were analyzed according to two sides factorialplan. The results showed that with replacement of 10% urea formaldehyde adhesive by tanninformaldehydeat both 12 and 15 min pressing times, thickness swelling (after 2 and 24 hoursimmersion in water) was decreased while internal bonding increased. There were no significanteffect on MOR and MOE values. In general, the results of present research showed thatreplacing the UF resin at lower levels of tannin is suitable as adhesive to manufactureparticleboard so that with replacement ratio of 90:10, the moisture properties of boards werevery close to permissible those of the exterior wood uses.
Research Paper
Mostafa Yahyavidizaj; Asieh khozini; Tagi Tabarsa
Abstract
In this study, Wheat straw particle boards were produced using a mixture of wheat straw andcotton bolls with Urea formaldehyde resin and its properties were reinforced with nanoclay.Cotton bolls and wheat straw particles were mixed at the ratio of 40:60, 60:40 and 80:20percents, respectively. Nanoclay ...
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In this study, Wheat straw particle boards were produced using a mixture of wheat straw andcotton bolls with Urea formaldehyde resin and its properties were reinforced with nanoclay.Cotton bolls and wheat straw particles were mixed at the ratio of 40:60, 60:40 and 80:20percents, respectively. Nanoclay was used at two levels of 0 and 2 percents based on oven driedweight of resin. Control samples were made of Wheat straw particle. Mechanical and physicalproperties (modulus of rupture, modulus of elasticity, internal bonding, water absorption andthickness swelling after 2 and 24h soaking in water) of the produced boards were measured.The results revealed an increase in cotton bolls in the mixture particles, leads to an increase ofthe bending strength, modulus of rupture and modulus of elasticity of the boards. The resultsalso indicated that water absorption and thickness swelling after 2 and 24h immersion in waterdecreased with increase in nano clay and cotton bolls percents.
Research Paper
َAbdolah Shakeri; Vahid Reza Safdari; Mehran Rohnia; Amir Nourbakhsh
Abstract
Coupling agents in wood fiber reinforced plastic composites play an important role inimproving compatibility and adhesion between polar wood fiber and non-polar polymermatrices by forming bridges of chemical bonds between the fiber and the matrix. Maleatedpolyethylene (MAPE) and diisocyanate (HMDI) are ...
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Coupling agents in wood fiber reinforced plastic composites play an important role inimproving compatibility and adhesion between polar wood fiber and non-polar polymermatrices by forming bridges of chemical bonds between the fiber and the matrix. Maleatedpolyethylene (MAPE) and diisocyanate (HMDI) are two most common coupling agents whichare subject to evaluation, singly and in mixture. Polypropylene and wood fibers werecompounded with Maleated polyethylene (MAPE) and diisocyanate (HMDI) in concentration of2% and 4% in solitary form and mixture form (HMDI %2 + MAPE %2) into pellets using acounter-rotating twin-screw extruder and mechanical test specimens were prepared by injectionmolding. The result showed that adding 4% MAPE and 2% HMDI individually lead to increasein flexural and tensile strength of the composites. Also adding (%2HMDI + %2MAPE) causedan increase of flexural, tensile and in particular the impact strength.
Research Paper
Mohammad Aghakhani; Abolgasem khazaeyan; Mehrab Madhoshi
Abstract
The aim of this study was to investigate the factors affecting surface quality of paulowniawood during milling by advanced computer numerical control (CNC) machine. For this aimwood logs were provided and were converted to proper sizes (2.5 x 10 x 15 cm) and then airdried. The Variable of this study ...
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The aim of this study was to investigate the factors affecting surface quality of paulowniawood during milling by advanced computer numerical control (CNC) machine. For this aimwood logs were provided and were converted to proper sizes (2.5 x 10 x 15 cm) and then airdried. The Variable of this study were spindle speed of machine (10000 and 18000 rpm),feeding rate (6 and 12 m/min), cutting depth (1and 5 mm), cutting method (down and upmilling)and cutting pattern (tangential and radial). Roughness of cut specimens edge wereevaluated by profilometer method according to ISO 13565 standard. For evaluation of surfacequality Abbott group parameters (Rpk, Rk, Rvk) were used. Degree of effective of theparameters was evaluated by fractional factorial design as completely random design atconfidence level of 95%. The result showed that spindle speed, cutting method and feed rate areinfluencing factors on surface quality of milled specimens and their effect was significant. Withincreasing spindle speed and decreasing feeding rate the roughness decreased and surfacequality improved. In up-milling cutting method, degree of roughness was higher andconsequently surface quality was inferior. It is to be noted that cutting method in comparison toother factors had the high influence on surface quality. The rest variable did now haveindependent influence on surface quality at 95% Confidence level.
Research Paper
Ali Pesaraklu; Mohammadreza Dehghani firoz abadi; Abolfazl Karegarfard; Taghi Tabarsa
Abstract
The objective of this study was to manufacture water resistant kenaf stalk particleboard.Twenty seven boards were produced using 170 °C steam treated kenaf particles, 30 and 60minute treatment time and three resin types include urea-formaldehyde, melamineformaldehydeand a mixture of fifty percent ...
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The objective of this study was to manufacture water resistant kenaf stalk particleboard.Twenty seven boards were produced using 170 °C steam treated kenaf particles, 30 and 60minute treatment time and three resin types include urea-formaldehyde, melamineformaldehydeand a mixture of fifty percent each. Physical and mechanical properties weremeasured and the results analyzed in a complete random design plan and by the factorialanalysis. The results showed that boards made from treated particles with 60 minute treatmenttime and Urea Formaldehyde resin had the highest bending strength. Modulus of elasticity(MOE) improved with an increase in treatment time. The greatest MOE was achieved with theboards produced using urea-formaldehyde and the greatest MOE was achieved with the boardsbonded with urea-melamine-formaldehyde resin. Moreover, with increasing treatment time from30 to 60 minutes internal bond strength (IB) reduced. Thickness swelling and water absorptionof the boards was significantly improved with increasing treatment time.
Research Paper
kezhal Moradyan Gilan; Mohammad Azad fallah; Amir abbas Shayghani akmal; Ali Abdolkhani
Abstract
This research was carried out with the aim of determining dielectric properties of bagasse unbleached soda pulp, long fiber kraft pulp and a mixture of both (20% kraft + 80% bagasse soda).The hand-sheets with 60 g/m2 basis weight were made after adjusting the freeness of pulps at levels of 200 ± ...
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This research was carried out with the aim of determining dielectric properties of bagasse unbleached soda pulp, long fiber kraft pulp and a mixture of both (20% kraft + 80% bagasse soda).The hand-sheets with 60 g/m2 basis weight were made after adjusting the freeness of pulps at levels of 200 ± 25 ml and 400± 25 ml and dried under mild condition around zero moisture content. Then the impregnation processes were carried out with mineral oil under vacuum at certain temperature. Finally the dielectric properties of impregnated papers including capacitance, insulation resistance, dielectric constant, and loss tangent were measured. The results showed that the refining give rise to enhance the dielectric properties in particular capacitance value. The dielectric properties of oil impregnated paper also increased. According to the preliminary results, unbleached soda bagasse pulp and its mixture with kraft pulp (20% Kraft -80% bagasse soda) found to be the suitable alternative with respect of dielectric applications for replacing kraft pulp, providing successful performance of the aging test.
Research Paper
Saeid Mehrabi
Abstract
Using non-destructive methods to study forest productivity and wood quality as well as annual growth variations deserve special importance. In this regard annual growth changes of Pinus eldarica include width of the spring and summer rings and percentage of tissue structure was determined using X-ray ...
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Using non-destructive methods to study forest productivity and wood quality as well as annual growth variations deserve special importance. In this regard annual growth changes of Pinus eldarica include width of the spring and summer rings and percentage of tissue structure was determined using X-ray method. Spring wood accounts as the effective factor for growth ring width in pine wood. The annual rings of the tree are thicker in the spring than in the summer time. Pine tree growth rate decreases with age and as the tree age rises, width of the ring as well as spring and summer wood width is lowered.
Research Paper
Negin Nikbin; Saeid Mahdavi; Hossein Kermanian; Omid Ramezani; Amir Mohssen Nazeri
Abstract
Native starch has relatively suitable characteristics including biodegradable properties, being widely used as an adhesive in the corrugated carton manufacturing companies. Corn starch is currently used in the companies for producing adhesives. In this study, fines of NSSC pulp as natural additive and ...
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Native starch has relatively suitable characteristics including biodegradable properties, being widely used as an adhesive in the corrugated carton manufacturing companies. Corn starch is currently used in the companies for producing adhesives. In this study, fines of NSSC pulp as natural additive and ammonium persulfate as chemical oxidative additive were used to improve the adhesion properties of corn starch. Fine was added at three levels of 5%, 10%, and 15% (based on oven-dry weight of starch) and ammonium persulfate similarly was mixed at 5 levels of 0.1, 0.2, 0.3, 0.4 and 0.5 grams. Addition of fine was lead to increasing adhesion strength (PAT) of the corrugating board to the amount of 25%, 35% and 43% respectively. This improvement could be due to increasing the number and strength of hydrogen bonding of fiber layers (corrugating and liner paper) and value of solid content. Addition of ammonium persulfate revealed that the method applied similar to mixing fine had no desirable results and the other methods should be used.
Research Paper
Soodeh Zhand; Masieh Masoudifar; Ahmad Reza Saraeian; Ali Ghasemiyan
Abstract
In this study the effect of alkaline pretreatment with 1% NaOH on physical, optical and mechanical properties and refining of NSSC (Neutral Sulfite Semi Chemical) wheat straw pulp were investigated. The wheat straw (Zagros Sp.) was obtained from croplands Golestan province. Splinted wheat straw was pretreated ...
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In this study the effect of alkaline pretreatment with 1% NaOH on physical, optical and mechanical properties and refining of NSSC (Neutral Sulfite Semi Chemical) wheat straw pulp were investigated. The wheat straw (Zagros Sp.) was obtained from croplands Golestan province. Splinted wheat straw was pretreated with 1% NaOH(on the basis of OD weight) at 70 degrees for 30 minutes. The main pulping was performed at 160 ˚C with the fixed ratio of 5:1 Na2S03 and NaOH. After pulping defibration was done by lab-refiner to 380±25ml (CSF) and total yield and changes in Kappa was determined. Hand sheets of 60 gr. /m² were made on the basis of TAPPI standard and physical, optical and mechanical properties determined. The results show that alkaline pre-treatment has a significant effect in increasing of physical, optical and mechanical properties. Calculating primary freeness of pulps indicates that by increasing chemical compounds and NaOH, freeness decreases and that by increasing chemical compounds paper density increases, whereas yield, caliper and bulk decrease.
Research Paper
Abolfazl Kargarfard; Amir Nourbakhsh; Fardad Golbabaei
Abstract
The objective of this study was to investigate utilization of pomegranate pruning residues as the core layer of the three layer particleboard. The percentage of the pomegranate residues varied as 100, 65 and 35% in the core layer of the eucalypt particleboard and three resin levels of 8, ...
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The objective of this study was to investigate utilization of pomegranate pruning residues as the core layer of the three layer particleboard. The percentage of the pomegranate residues varied as 100, 65 and 35% in the core layer of the eucalypt particleboard and three resin levels of 8, 10 and 12 % (based on the weight of the wood particles) were applied in the core layer. Resin dosage in the surface layer was kept at 12 %. The strength and physical properties were measured and analyzed applying factorial model based on completely randomized design. The results revealed that if 65% pomegranate residues are used in the core layer, the modulus of rupture and modulus of elasticity were the highest and the combined effect of both variables on the properties were statistically significant. The highest value of the modulus of rupture and modulus of elasticity obtained in the case of 10% resin in the core layer and 100% pomegranate residues followed by 8% resin in the core layer and 65% pomegranate residues. The combined effect of both variables on internal bonding of the boards was statistically significant and the highest internal bonding was reached if 8% resin and 65% pomegranate residues were used in the core layer. The effect of resin dosage on thickness swelling after 24 hours immersion in water was statistically significant. The results indicated that pomegranate tree pruning could be used for the particleboard manufacturing.
