Amir Nourbakhsh; Abolfazl Kargarfard; Reza Hajihassani; Saman Ghahri; Fardad Golbabaei
Abstract
In this study, the resistance properties of nanocomposite plastic wood produced using 5 levels of cellulosic wastes (bagasse, corn stalk, rice stalk, sunflower stem and canola stem), three levels of nanomaterials (carbon nanotubes, nano silica, nanoclay) ) And urban polymer wastes (PP polypropylene and ...
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In this study, the resistance properties of nanocomposite plastic wood produced using 5 levels of cellulosic wastes (bagasse, corn stalk, rice stalk, sunflower stem and canola stem), three levels of nanomaterials (carbon nanotubes, nano silica, nanoclay) ) And urban polymer wastes (PP polypropylene and HDPE heavy polyethylene, etc.) were investigated. In order to chemically bind the wood / polymer fiber composites, chemicals and reinforcers (pairing agents) have been used due to the hydrophilic properties of cellulose fibers and plastic drainage. Extruders and hot presses were used to study the mechanical properties and bonding of composites. The results showed that the use of HDPE heavy polymer wastes increased tensile strength, flexural modulus and impact resistance to polypropylene wastes. Regarding the use of agricultural wastes and wastes in the construction of wood-plastic composites, in general, the results have shown that the addition of agricultural waste wastes in several types of plastic wood has significantly improved the bending and tensile properties. Among them, the bagasse stem has a significant advantage over other lignosullose materials. The use of polymer waste and agricultural waste using nano-silica has shown the best results of resistances. In general, the results have shown that the use of agricultural fiber wastes as reinforcers in plastic wood polymers have the expected mechanical properties.
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.
Vahid reza ُSafdari; Nima Eskini; Ajang Tajdini; Vlima Bayramzadeh
Abstract
Wood anatomy in addition to genetic is affected by environmental factors. One of the environmental factors is soil erosion which affects anatomical properties of roots considerably. Juniperus excelsa is one of Iranin indigenous softwood and has longevity and anatomical properties of its root in two conditions: ...
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Wood anatomy in addition to genetic is affected by environmental factors. One of the environmental factors is soil erosion which affects anatomical properties of roots considerably. Juniperus excelsa is one of Iranin indigenous softwood and has longevity and anatomical properties of its root in two conditions: inside of soil and exposed one can reveal effects of soil erosion on wood anatomical properties of root. So many roots and barks of trees in inside of soils and exposed have been sampled and many micro-sections prepared by microtome and anatomical properties were investigated. Results showed that wood roots under soil conform of one row of late-wood and by exposing the lumen area of tracheids in early-wood and late-wood were decreased and the cells appear thicker and late-wood portion increased. The axial parenchyma inclusion of dark resins in exposed roots observed frequently. Meanwhile by exposing of roots the thickness of bark decreased and the thickness of phloem and periderm in exposed root is not as wide as normal roots.
Sina Modirrahmati; Ahmad Jahan-Latibari; Mansor Minaei
Abstract
The influence of nanoclay addition on the strength properties of HDPE/ Wheat straw powder Composite was investigated. Composites compounds were produced using 73%HDPE, 25% wheat straw powder and 2% MAPE and three amounts of nanoclay (1, 2, and 3% of composite compound). First, HDPE and nanoclay was melt- ...
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The influence of nanoclay addition on the strength properties of HDPE/ Wheat straw powder Composite was investigated. Composites compounds were produced using 73%HDPE, 25% wheat straw powder and 2% MAPE and three amounts of nanoclay (1, 2, and 3% of composite compound). First, HDPE and nanoclay was melt- mixed and after cooling, the extrudate was milled to fine granules. This granules were then melt compounded with pre-weighted amount of wheat straw powder and MAPE followed by injection moulding to produce test specimens. The flexural, tensile and impact strength were measured. The results showed that the addition of nanoclay to the composite improved flexural strength and modulus, tensile strength and modulus. However the notched Izod strength was reduced.
Sina Modirahmati; Ahmad Jahan Latibari; Amir Nourbakhsh; Mehran Roohnia; Mansor Minaei
Abstract
The impact of nanoclay addition on the properties of polypropylene/ OCC fibers/ nanoclay Composite was investigated. Composites were prepared using 67% polypropylene, 30% OCC fiber, 3% MAPP and three dosages (2.5, 5, 7.5% based on total weight of PP/OCC/MAPP) of nanoclay. Premix- ...
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The impact of nanoclay addition on the properties of polypropylene/ OCC fibers/ nanoclay Composite was investigated. Composites were prepared using 67% polypropylene, 30% OCC fiber, 3% MAPP and three dosages (2.5, 5, 7.5% based on total weight of PP/OCC/MAPP) of nanoclay. Premix- melting of nanoclay and polypropylene was used to add nanoclay to the composite mixture. Pre-mixed nanoclay/ polypropylene was melt-mixed with OCC fibers and MAPP and then test samples were made using this compound. The results revealed that addition of nanoclay to polypropylene/OCC fiber composite reduced flexural strength , tensile strength and notched Izod impact strength, but the flexural modulus and tensile modulus of final composite were improved significantly. The influence of nanoclay addition on flexural strength and tensile modulus of composite was statistically significant at 99% level whereas its effect on tensile strength was statistically significant at 95%. However, the effect of nanoclay on both flexural modulus of elasticity and impact strength was not statistically significant. The addition of nanoclay to the composite reduces the bonding between polypropylene and OCC fibers. In the case of notched Izod strength, nanoclay particles generated stress concentration point within the composite structure initiating easier failure. Water absorption after 2 and 24 hours immersion was reduced.
Alireza Asgari; Ahmad Jahan latibari; Seiad Javad Sepidedam
Abstract
The impact of Multi Wall Carbon Nano Tubes addition on mechanical properties, water absorption and thickness swelling of polypropylene/old corrugated container (OCC) fiber composites was investigated. Polypropylene/ OCC fiber composite was prepared using 30% OCC fiber, 67% polypropylene and 3% MAPP. ...
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The impact of Multi Wall Carbon Nano Tubes addition on mechanical properties, water absorption and thickness swelling of polypropylene/old corrugated container (OCC) fiber composites was investigated. Polypropylene/ OCC fiber composite was prepared using 30% OCC fiber, 67% polypropylene and 3% MAPP. Three levels of multi wall carbon nano tubes (1, 2, 4% based on the weight of fiber/polypropylene/MAPP mixture) were added. Composite compound was prepared using a Haake mixer and the test samples were extruded. The results of strength measurement indicated that when 1 or 2% multi wall carbon nanotubes were added, Izod impact strength and flexural strength improved. Higher flexural modulus of elasticity was reached as either 2 or 4% multi wall carbon nano tubes was added. The performance of 4% multi wall carbon nano tubes on flexural modulus of elasticity was superior. Lower water absorption and thickness swelling levels were observed, as 1% multi wall carbon nano tubes was added.
Babak Mirzaei; Mehdi Tajvidi
Abstract
Stress relaxation behavior of milled newsprint/HDPE composite containing coupling agent was studied. Composites containing 25 and 50% filler in weight were produced, and were compared to neat polymer. Melt blending followed by injection molding was the manufacturing process. Results showed that incorporating ...
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Stress relaxation behavior of milled newsprint/HDPE composite containing coupling agent was studied. Composites containing 25 and 50% filler in weight were produced, and were compared to neat polymer. Melt blending followed by injection molding was the manufacturing process. Results showed that incorporating filler to polymer increases the flexural strength and modulus. It was observed that higher stress is needed to maintain higher strain levels. Furthermore, comparing the stress ratio patterns revealed that the difference among relaxation of different samples develops over time. Power law computed parameters showed that higher strain level results in higher stress relaxation amplitude (A) and lower time exponent (t). It was also found that, almost complete linear relationship could be established between strain level and parameter A, and the effect of strain level on parameter A is more pronounced at higher filler contents.
Pulp and paper
Hamd Unesi kord khalili; Mehran Jalilvand; Rabi Behroz
Abstract
The purpose of this study was to investigate effects of different loading levels and addition of urea formaldehyde and polyethylene on the creep behavior of composites made from wastes of OCC recycling mills. The composites manufactured by hot press method and three-point ...
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The purpose of this study was to investigate effects of different loading levels and addition of urea formaldehyde and polyethylene on the creep behavior of composites made from wastes of OCC recycling mills. The composites manufactured by hot press method and three-point bending test performed before creep test. In general, the results showed positive effects of additive materials such as urea formaldehyde and polyethylene on the creep behavior of the composites. While adding UF and PE decreased primary and final creep as well as return deformation percentage of the composites. Also the obtained results indicated that remaining creep had higher sensitivity to loading levels compared to primary and final creep. Also the increase of the load levels from 20% to 30% led to an increase in creep content of the composites.
Physics and Mechanical Wood
Morteza Khorami; Ahmad amin Khalili tabas; Amir Nourbakhsh
Abstract
Cement board without fibres has low flexural strength and fails in small strain. To solve this problem and enhance other characteristics, the fibres are applied. Asbestos fibres which have individual properties have been used for reinforcing cement composites since the early 20th century. However in ...
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Cement board without fibres has low flexural strength and fails in small strain. To solve this problem and enhance other characteristics, the fibres are applied. Asbestos fibres which have individual properties have been used for reinforcing cement composites since the early 20th century. However in this decade, most countries have been banned the use of asbestos fibres in construction industries, because of its effect on human healthy. Natural fibres are one of the suitable alternatives for cement board production that have a good compatibility with cement matrix. In this research, to recognize the flexural behaviour which is the one of the most important characteristics for cement board, many laboratory samples have been made by three kinds of fibres and tested. These fibres obtained from agricultural wastes such as bagasse, wheat and eucalyptus. The scanning Electronic Microscopic studies were carried out to clarify the microstructures of composites. The results show that among the all types of fibres, bagasse has the most effect on increasing the flexural strength capacity for cement composite boards.
