Research Paper
Hussein Samouei; Farshid Faraji; Loya Jamalirad; Vahid Vaziry
Abstract
In this study, the effect of adding WTR on the physical and mechanical properties of OSB production from Paulownia wood was investigated. Fixed factors of this research are: Strands of Paulownia species with dimensions of 0.20 × 0.8 × 120 mm, Phenol formaldehyde resin (in strands 8% dry weight ...
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In this study, the effect of adding WTR on the physical and mechanical properties of OSB production from Paulownia wood was investigated. Fixed factors of this research are: Strands of Paulownia species with dimensions of 0.20 × 0.8 × 120 mm, Phenol formaldehyde resin (in strands 8% dry weight of strands and in waste tire powder 10% dry weight of tire powder). Laboratory boards with a thickness of 17 mm, dimensions of 40 × 40 cm with a nominal density of 0.5 g / cm3, pressing time was 10 minutes and the pressing temperature was 180 ° C. The OSB were production made of 3 layers (top and bottom layer 25%, and middle layer 50% by weight). The OSB were made of 3 layers (top and bottom layer 25%, and middle layer 50% by weight). Variable factors are: the amount of tire powder was 10, 20 and 30% and the distribution of tire powder particles in 3 layers was scattered in the surface layers, in the middle layer and in all three layers. The mechanical and physical properties of the boards were measured as defined in relevant European standards test methods EN 300. The results of physical properties showed, that increasing the waste tire powder improved the thickness swelling of the boards, so that the minimum amount of thickness swelling in the maximum presence of waste tire powder was 30% and scattered in all three layers. The highest amount of mechanical strength was observed in panels made of 10% tire powder, so that the highest amount of MOR in 10% of tire powder and scattered in all three layers and the highest amount of MOE and IB in The same level of consumption was obtained by dispersing the tire powder in the surface layers.
Research Paper
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.
Research Paper
Reza Oladi; Hamidreza Yavarian; MohammadHossein Sadeghzadeh Hallaj; Kambiz Pourtahmasi
Abstract
Tamarisk is a drought-resistant tree that is important environmentally and has industrial applications in some countries. The aim of this study was to compare different populations of this species in terms of diameter growth rate (growth ring width), physiological adaptability (vascular characteristics) ...
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Tamarisk is a drought-resistant tree that is important environmentally and has industrial applications in some countries. The aim of this study was to compare different populations of this species in terms of diameter growth rate (growth ring width), physiological adaptability (vascular characteristics) and wood application characteristics (fiber biometry). The study was conducted on ten-year-old saplings of six tamarisk populations that had previously been collected from different regions of Iran (Qom, Kashan, Khash, Zabol, Garmsar and Yazd) and planted in Garmsar. The results showed that Garmsar population has the largest diameter and radial growth among populations. This population chose the best strategy for adapting to cold and dry climates by keeping the vessels small and significantly increase their number, instead. This has been the reason for its better radial growth. Although the biometric properties of fibers and paper ratios showed significant statistical differences between populations, these differences were not so great as to have a significant impact on the quality of the resulting paper in practice. Therefore, although the population of Yazd was of better quality in terms of paper parameters, the selection of the best population for industry should not be only based on fiber biometry and other features such as production volume, adaptability to habitat and survival rate of seedlings should be given more importance. The positive correlation between the width of the growth rings and the length of the fibers from the perspective of wood cultivation is very favorable because the treatments that increase the growth rate will also improve the fiber properties. In general, it can be concluded that Garmsar population is the best option for planting and cultivating tamarisk in terms of adaptability to environment and wood farming.
Research Paper
Saeed Mahdavi; Mohammad Hadi Rezvani
Abstract
Kenaf as an industrial plant can play an important role in providing shortage of virgin fiber for paper and board based on the history of cultivation in Iran. Harvesting time of kenaf is one of the most important economic-technical aspect, so the growth rate of kenaf (variety of Cuba) and the weight ...
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Kenaf as an industrial plant can play an important role in providing shortage of virgin fiber for paper and board based on the history of cultivation in Iran. Harvesting time of kenaf is one of the most important economic-technical aspect, so the growth rate of kenaf (variety of Cuba) and the weight ratio of bast, core and pith individually were measured at 5, 6 and 7 months after planting and kenaf biomass was determined after 7 month. Soda-AQ pulping from kenaf bast fiber was adjusted at 14% and 16% chemical charges, 175°C, 120 min., liquor to bast fiber of 5:1 and adding 0.2% AQ. Handsheet was made by the bast pulp from the three harvested times with base weight of 110 g/m2. The results showed that by increasing the harvest period from 5 to 6 and 7 months, stalk height and diameter increased 9% and 5%, and vice versa, respectively. The weight ratio of kenaf bast to core has decreased by increasing of harvest time. Dry and green biomass of kenaf was determined at 33.1 and 7.7 t/ha, respectively. Screen yield, kappa number, and reject were of pulp were measured for combinations of optimal cooking in range of 48.8% to 52.9%, 35.4 to 72.6, and 0.92% to 2.5%, respectively. The beating energy consumption of pulp that prepared from 7 month harvesting time was greater than the others. Optimal conditions were determined as harvesting time of 5 month and cooking variables of 120 min, 165 °C and 16% NaOH for carton top liner. Handmade paper properties compared to kraft liner paper confirms the superiority of paper made from virgin kenaf bast fiber according to national standard of Iran (ISIRI 3054).
Research Paper
Aisona Talaei; Vahid Heydari
Abstract
In the present study, the functional properties of medium-density fiber board made with formaldehyde urea resin as a control with MDF made with chitosan and carboxylic acids were investigated and compared. Various compounds including chitosan acetate solution, chitosan acetate –butane tetra carboxylic ...
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In the present study, the functional properties of medium-density fiber board made with formaldehyde urea resin as a control with MDF made with chitosan and carboxylic acids were investigated and compared. Various compounds including chitosan acetate solution, chitosan acetate –butane tetra carboxylic acid solution, chitosan acetate -citric acid solution and citric acid solution were investigated. The chemical structure of specimens was investigated by infrared spectroscopy (FTIR). The results of spectroscopy clearly showed the difference in the use of different compounds. The formation of cross-links between cellulose chains and carboxylic acids was confirmed, as well as the formation of hydrogen bonds between chitosan and lignin. Specimens made with the combination of acetate chitosan-BTCA showed better dimensional stability. Also, the internal bonding of MDF specimens made with chitosan acetate solution was higher than controls. Boards made of Chitosan acetate -BTCA compound can be considered as a successful substitute for urea-formaldehyde adhesive due to its better dimensional stability and good internal bonding.
Research Paper
Ali Kazemi Tabrizi; Habibollah Khademi Eslam; Amir Hooman Hemmasi; Behzad Bazyar; Vahid Atghia
Abstract
Abstract In this study, acidified Luffa (AHS@L), by sulfonic acid, as an effective and biodegradable solid acid catalyst was produced. The synthesized catalyst was characterized by TGA, SEM, XRD and FTIR, and the results indicated that modified Luffa flour had an intense acidic property. The FT-IR analyze ...
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Abstract In this study, acidified Luffa (AHS@L), by sulfonic acid, as an effective and biodegradable solid acid catalyst was produced. The synthesized catalyst was characterized by TGA, SEM, XRD and FTIR, and the results indicated that modified Luffa flour had an intense acidic property. The FT-IR analyze show a broad peak at 3400cm-1 that improve the acidification of the Luffa surface. Also the XRD analyze clearly show the change in the morphology of Luffa after acidification. The TGA analyze show us the heat resistance of the catalyst up to 245 ° C and the SEM images clearly showed that the catalyst surface was hydrated as a result of acidification. The synthesized catalyst was used to protect the amines in the N-tert butyl carbamate reaction under solvent-free conditions at room temperature. Different types of aliphatic and aromatic amines have been produced as related monocarbamates with excellent yields and short reaction times. This method was mild and selective and has advantages such as heterogeneous catalysis, low cost and catalyst recovery capability.
Research Paper
Mohamad Bai; Behzad Bazyar; Habibollah Khademi Eslam; Abdolah Najafi; Amir Hooman Hemasi
Abstract
In this study, the effect of cellulose nanofibers and silicon nanoparticles on the properties of nanocomposites made with polyvinyl alcohol was studied and the physical, mechanical and morphological properties of nanocomposites were investigated. Samples were prepared by casting with different ratios ...
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In this study, the effect of cellulose nanofibers and silicon nanoparticles on the properties of nanocomposites made with polyvinyl alcohol was studied and the physical, mechanical and morphological properties of nanocomposites were investigated. Samples were prepared by casting with different ratios of 0, 5 and 10% by weight. The morphology of nanocomposites was examined by scanning electron microscopy. Observations of water vapor permeability and water uptake by adding cellulose and nanoxide oxide nanofibers in pure polyvinyl alcohol control film and nanocomposite films with different compositions were significantly different from each other. Tensile strength of nanocomposites showed that increasing the amount of cellulose nanofibers and silicon nanoparticles increased the tensile strength and the percentage of elongation increased with the addition of cellulose nanofibers and silicon nanoparticles decreased. The results of the present study show that the addition of small amounts of nanocellulose fibers and silicon nanoparticles strengthens the polyvinyl alcohol polymer and improves the physical and mechanical properties and increases the performance of nanocomposites.
