Masoudreza Habibi; Saeed Mahdavi; Vahid Pezeshki; Farshid Niromand; Hossein Familian
Abstract
This study was carried out to investigate the effect of Bagasse alkaline treatment (hydroxide sodium) on Medium Density Fiberboard (MDF) properties. For this purpose, wet depitted and storage bagasse was used. Cooking process was done for fibers preraring in 10 liters digester. Liqure to bagasse ratio ...
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This study was carried out to investigate the effect of Bagasse alkaline treatment (hydroxide sodium) on Medium Density Fiberboard (MDF) properties. For this purpose, wet depitted and storage bagasse was used. Cooking process was done for fibers preraring in 10 liters digester. Liqure to bagasse ratio was 10 to 1. Hydroxide sodium content was 0%, 4% and 5% based on oven dry weigth of bagasse. Cooking time and temperature were 5 min and 170 centigrade respectively. Fiber slides were obtained by using optical microscope. Chemical components such as holocelloulose and lignin contents were determined. Liqures pH was mesearued before and after cooking. Urea formaldehyde resin was used for MDF producing. Resin content was 12% based on oven dried bagasse. Bending properties (MOR & MOE), internal bonding and thickness swelling of the boards were determined based on EN-310, EN-319 and EN-317 respectively. The results showed that when using 4% alkaline treatment, were seen the minimum fibers cutting and crusing. With increasing of hydroxide sodium content, lignin content decreased and holocelloulose increased. Bulk density increased when increasing hydroxide sodium content. The maximum MOR, MOE and internal bonding of the boards were obtained in 4% hydroxide sodium content. Also thickness swelling of the boards was minimum.
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
Composite wood products
masoudreza habibi; Hossein Hosseinkhani; Saeid Mahdavi; Fardad Golbabaei
Abstract
In this study Medium Density Fiberboard was produced from 4 year old Poplar clones (P.e. costanzo, P.e. 564.41, P.e. vernirubensis). Fibers length of P.e. costanzo, P.e. 564.41, P.e. vernirubensis were measured 805, 751 and 764 micron respectively. Also fibers diameter of these clones were determined ...
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In this study Medium Density Fiberboard was produced from 4 year old Poplar clones (P.e. costanzo, P.e. 564.41, P.e. vernirubensis). Fibers length of P.e. costanzo, P.e. 564.41, P.e. vernirubensis were measured 805, 751 and 764 micron respectively. Also fibers diameter of these clones were determined 25.76, 25.44, 25.23 micron respectively. Three steaming times (5, 10, 15 minutes) were used for fibers preparation. Also three press times (3, 4, 5 minutes) and two resin contents (9%, 11%) were applied for MDF production. Thus physical and mechanical properties of boards such as MOE, MOR, IB and Thickness Swelling after 2 and 24 hours were investigated. The physical and mechanical properties of boards were tested in based on EN standard. The measurements of bending properties and IB of MDF revealed that increasing steaming time caused to decrease MOE, MOR and IB. The highest of MOE, MOR and IB were obtained in 5 minutes steaming time. Also the lowest values of Thickness Swelling after 2 and 24 hours were obtained in 15 minutes steaming time. The influence of press time on bending properties was not significant. The highest of IB was obtained in 5 minutes press time. As expected, boards demonstrated better properties at higher resin content.
Composite wood products
masoudreza habibi; Hossein Hosseinkhani; Saeed Mahdavi
Abstract
In this study , MDF was produced from three clones of poplar (P.e. vernirubensis, P.e. costanzo, P.e.561.41). Age clones of poplar were 4 and 12 years. In addition to age variation , the influence of three production variables (steaming time , press time and resin content on MDF properties were investigated. ...
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In this study , MDF was produced from three clones of poplar (P.e. vernirubensis, P.e. costanzo, P.e.561.41). Age clones of poplar were 4 and 12 years. In addition to age variation , the influence of three production variables (steaming time , press time and resin content on MDF properties were investigated. Variations of each variable were as follow:
- Steaming time (5, 10, 15 minutes)
- Press time (3, 4, 5 minutes)
- Resin content (9%, 11%)
Fiber length and fiber diameter of 4 and 12 years old poplar clones (P.e. vernirubensis, P.e. costanzo, P.e.564.41) were measured 746, 25.23, 805, 25.76,751, 25.44 and 902, 31.62, 995, 29.23, 899, 26.83 micron respectively.
MOR, MOE, IB, TS2, TS24 were determined according to DIN standard.
Increasing steaming time decreased board's internal bond and bending properties. As expected, boards demonstrated better properties at higher resin consumption. Minimum of boards thickness swelling were obtained at 15 minutes steaming time because of fiber hydrophilic properties were decreased. There are no significant differences between 4 and 12 years old of clones for bending properties and IB of boards. The effect of age variation is only significant difference on thickness swelling of boards which it is lower for 4 years old clones.
Composite wood products
masoudreza habibi; Hossein Hosseinkhani; Saeed Mahdavi
Abstract
In this study, MDF was produced from Rice straw. Variables for Medium Density fiberboard making were as following:
- Resin content 8, 9.5, 11 (percent baced on oven dry weight of fiber)
- Press time (4, 5, 6 minutes).
There were 9 treatment conditions by combinations of the above factors and three ...
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In this study, MDF was produced from Rice straw. Variables for Medium Density fiberboard making were as following:
- Resin content 8, 9.5, 11 (percent baced on oven dry weight of fiber)
- Press time (4, 5, 6 minutes).
There were 9 treatment conditions by combinations of the above factors and three replications for each combinations which resulted in producing 27 boards.The other production variables were constant.
The anatomical properties of Rice straw such as fiber length, fiber diameter were measured respectively 810, 10.1 micron. L/D ratio of Rice straw fiber was measured 80.2. The physical and mechanical properties of MDF were determined according to DIN standard. The measurements of bending properties and IB of MDF revealed that the highest MOR, MOE, IB were obtained in variables combination of 11% resin content and press time of 6 minute and at this conditions thickness swelling of boards were the lowest.
According to Duncans, test method the effects of press times (4 & 5 minutes) and resin content (8% & 9.5%) on bending properties were not significant statistically.
