Eysa Rezazadeh; Ramin Vaysi; Mogtaba Soltani; Abdollah Najafi; S. ESHAGH EBADI
Abstract
This study was aimed to investigate the effect of polyalumium chloride and nano-chitosan on optical and mechanical properties of chemi-mechanical pulp. For this purpose, some of the bleached CMP pulp of Mazandaran Wood and Paper Industries (MWPI) were randomly selected as a control sample. In addition, ...
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This study was aimed to investigate the effect of polyalumium chloride and nano-chitosan on optical and mechanical properties of chemi-mechanical pulp. For this purpose, some of the bleached CMP pulp of Mazandaran Wood and Paper Industries (MWPI) were randomly selected as a control sample. In addition, the polyalumium chloride were used as a white powder at 4 levels of 0, 0.5, 1, and 1.5%. The nano-chitosan was then added to the CMP pulps suspensions at 3 levels of 0, 1, and 2%, as well. Hand-sheets with a basis weight of 60 gr/m2 were prepared from the mentioned pulps. The optical and mechanical properties were then measured and compared using TAPPI standard test methods. The results showed that by adding polyalumium chloride and nano- chitosan(separate) to the CMP pulps, brightness, opacity, greenness,tear, tensile, burst strengths, air resistance increased , but Cobb 60 and a* factor decreased. On the other hand, with the addition of nano-chitosan and polyalumium chloride to CMP pulp, the brightness and greenness increased, but tensile, burst, tear strengths, air resistance, Cobb 60 and opacity low decreased and then suitable increased. Moreover, the findings showed that by simultaneous adding 1% polyalumium chloride and 2% nano-chitosan(separate) and 2% nano-chitosan with 1.5% polyalumium chloride to the CMP pulp, most of the paper properties were improved. Therefore, it can also be introduced as the best treatment.
Composite wood products
Vahid Tazakor Rezaie; abdolah Najafi; Ahmad Sinaie
Abstract
In this study, effect of nano-wollastonite on fire resistance characteristics of wood flour/polypropylene composite was investigated. The composites samples were manufactured using a dry blend/hot press method. In this study, the dried wood flour of beech as the filler in a 60%, poly propylene as the ...
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In this study, effect of nano-wollastonite on fire resistance characteristics of wood flour/polypropylene composite was investigated. The composites samples were manufactured using a dry blend/hot press method. In this study, the dried wood flour of beech as the filler in a 60%, poly propylene as the matrix in a 37% and polyethylene grafted with maleic anhydride as the coupling agent in a 3% total weight was used. Also, nano-wollastonite was used in four levels of dried wood flour loading (0, 1, 3 and 5%). Nominal density and dimensions of the composites were 1 g/cm3 and 1*20*25 cm, respectively.Bending strenght according to ASTM standard and Fire resistance characteristics such as, flammability duration, duration of flame after removing the burner, duration of glow after removing the burner and mass reduction were measured acceding to ISO 11925. Results indicated that by increasing the nano-wollastonite increases the bending strengh,MOE and flammability duration increased but mass reduction, duration of flame and duration of glow decreased. Also the dispersion of nano-wollastonite in composites was evaluated by Filed Emission Scanning Electron Microscopy (FE-SEM).
Composite wood products
Abdollah Najafi
Abstract
In this study, chemical treatments of rice husk flour on physical and mechanical properties of rice husk flour / high density polyethylene composites were studied. Rice husk was milled and its flour through the sieve of 60 meshes was selected for using. Initially, dried rice husk flour was subjected ...
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In this study, chemical treatments of rice husk flour on physical and mechanical properties of rice husk flour / high density polyethylene composites were studied. Rice husk was milled and its flour through the sieve of 60 meshes was selected for using. Initially, dried rice husk flour was subjected to chemical treatment with acetic acid and then, was mixed with powder of high density polyethylene at weight ratio of 60% filler loading in an internal mixer. After milling of mixed matreials, samples of composites were made by injection moulding method. Physical and mechanical properties of treated rice husk flour / high density polyethylene composites were compared to untreated composite and a composite including a PE-g-MA coupling agant (MAPE) that were produced in the same method. Dynamic Mechanical-Thermal Analyze (DMTA) of specimens in the temperature range of -50 to +150 ◦C were taken and storage modulus and loss modulus were measured. FT-IR spectra of chemical treatments of rice flour husks were also investigated to what extent changes in the functional groups being studied. Results of FT-IR indicated that the chemical treatment of rice husk led to a change of OH group absorbance on 3436 cm-1 and a peak in the region of 1741 cm-1 related to functional group of C=O. Results of tests also indicated that all of properties in composites including of treated rice husk flour with acetic acid were improved.
Mechanical conversion of wood and wooden fittings
Abdolah Najafi; Mehdi Faezipoor; Habibalah Khademi eslam; Saeid Kazemi; Amir homan Hamasi
Abstract
In this study flexural properties Wood-plastic composites(WPCs), the composites made from high density polyethylene(virgin, recycled and mix of them) and four types lignocellulosic fillers (wood sawdust, sanding of MDF, particleboard sawdust and rice hull) at %60 by weight fiber loadings were manufactured ...
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In this study flexural properties Wood-plastic composites(WPCs), the composites made from high density polyethylene(virgin, recycled and mix of them) and four types lignocellulosic fillers (wood sawdust, sanding of MDF, particleboard sawdust and rice hull) at %60 by weight fiber loadings were manufactured using a dry blend/hot press method. Nominal density and dimensions of the panels were 1g/cm3 and 35Î35Î1cm, respectively. After conditioning, flexural properties of the panels including flexural modulus and flexural strength were determined. The results show the flexural modulus and strength wood plastic composites containing sanding MDF and particleboard sawdust were higher than those made from other fillers. The flexural modulus and strength were affected by kind of high density polyethylene (virgin or recycled
