• 펄프종이기술
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• 제47권3호
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• pp.24-33
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• 2015

Linerboards containing wood flours were developed to increase solid contents in wet pressing process. Presence of wood flours in recycled fibers allowed passage of pressurized water at high wet pressing pressure, and increased solid contents while keeping the bulk of the board. The amount of wood flour addition should be controlled based on the intensity of the wet pressing pressure and the properties of the wood flours. Addition of cationic starch to the wood flour containing OCC furnish showed synergic increase of solid content and strength properties. Shapes of the wood flours such as spherical and rod type added to OCC furnish affected largely their solid content, drainage, and board physical properties.

• Journal of the Korean Wood Science and Technology
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• 제37권6호
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• pp.505-516
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• 2009

본 연구에서는 다른 목재수종과 다른 입자크기의 목분 및 상용화제를 첨가한 Wood Plastic Composites (WPC)를 제조한 후 다양한 물성을 평가하였다. 먼저 3가지 다른 수종으로부터 얻은 목분의 화학조성분의 함량이 화학분석으로부터 얻어졌다. 낙엽송(Larix kaempferi Lamb.), 상수리(Quercus accutisima Carr.), 다릅나무(활엽수, Maackia amuresis Rupr. et Maxim)로부터 40~60 mesh와 80~100 mesh의 목분을 제조하여 열가소성 폴리머의 일종인 폴리프로필렌(polypropylene)에 용융 압출 및 사출하여 복합재를 제조한 후 인장강도, 휨강도, 충격강도 및 현미경 분석을 수행하였다. 알파 셀룰로오스는 상수리나무가 43.6%, 다릅나무가 41.3%, 낙엽송이 36.2%였다. 리그닌의 함량은 낙엽송이 31.6%로 가장 높았으며, 상수리나무가 24.4%로 가장 낮았다. 추출물의 함량은 낙엽송이 8.5%, 다릅나무와 상수리나무는 각각 4.4%와 3.9%였다. 알파 셀룰로오스의 함량이 증가하고 리그닌과 추출물의 함량이 감소할수록, WPC의 인장 및 휨강도 특성이 높았다. 같은 목분의 첨가량에서 작은 입자크기의 목분(80~100 mesh)이 큰 입자크기의 목분(40~60 mesh)에 비하여 WPC의 인장 및 휨강도 특성이 크게 높았다. WPC의 충격강도는 목재수종에 따른 영향이 적었으나, 입자의 크기가 큰 목분을 첨가한 WPC의 충격강도가 대체적으로 높았다. 상용화제인 Maleated polypropylene (MAPP)의 첨가는 수종과 다른 입자크기에 관계없이 인장강도, 휨강도 및 충격강도를 증가시켰다. 현미경 분석 결과, MAPP의 첨가에 의해 목분과 PP수지 간의 계면 결합력이 개선됨을 확인할 수 있었다.

• Journal of the Korean Wood Science and Technology
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• 제31권3호
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• pp.42-49
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• 2003

The objective of this research was to investigate the possibility of using rice husk flour as a partial substitute for the wood particles used as the raw material for manufacturing particleboards, by examining the physical and mechanical properties of the rice husk flour-wood particleboard as a function of the type of urea-formaldehyde resin used. Commercial wood particles and two types of rice husk flours (A type (30 ㎛), B type (300 ㎛)) were used. E₁ and E₂ class urea-formaldehyde resin was used as the composite binder, combined with 10 wt.% NH₄Cl solution as a hardener. Rice husk flour-wood particleboards with dimensions of 27×27×0.7 (cm) were manufactured at a specific gravity of 0.7 with rice husk flour contents of 0, 5, 10, and 15 (wt.%). We examined the physical properties (specific gravity and moisture content), mechanical properties (three point bending strength and internal bonding) of the composite. In general, it can be concluded that composites made from rice husk flours are of somewhat poorer quality than those made from wood; however, blending in small amounts of rice husk flour (e.g., 5% to 10% by weight) may have no significant impact on quality.

• Journal of the Korean Wood Science and Technology
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• 제4권1호
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• pp.28-32
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• 1976

This study was carried out to know the adaptability of barley flour, potato flour and white ash as extender and filler of urea-formaldehyde resin for plywood as a substitute material of wheat flour. The extenders and filler used at this study were extended by several groups of percentages. Shear strength, moisture contents, and specific gravities were compared among tested groups. The results obtained are summarized as follows. 1) Wet and dry shear strength of plywoods extended by 10% barley flour, 30% potato flour, and wheat flours were shown better results than non extended plywoods. 2) There was no significant difference between plywoods extended until 50% barley flours and non extended plywoods. 3) Shear strength of plywoods extended by 50% potato and 100% barley flours were shown worse result than non extended. 4) Dry and wet shear strength of plywoods extended by white ash were shown worst result. 5) The plywoods extended by potato flours were shown not only better shear strength, but also considered more profitable cost for extending.

• 펄프종이기술
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• 제46권6호
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• pp.8-15
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• 2014

The increase of wet web solid content in wet pressing will save drying energy greatly. We applied wood flours as spacers to increase the old corrugated container (OCC) solid contents in wet pressing. The mixed furnish of OCC and wood flours of 3-5% (wt/wt) increased bulk and drainage rate, and by increasing wet pressing pressure, its solid content started to be higher than 100% OCC furnish at more than 50% solid content level. Addition of cationic starch and drainage aid to the mixed furnish increased solid content further up to around 2%. Cationic starch addition compensated or exceeded the loss of tensile and compressive strength caused by the addition of wood flour, but drainage aid did not. Cationic starch also improved the stretch of the OCC, which could mitigate cracking at folding in boxboard.

• 한국기계가공학회지
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• 제18권1호
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• pp.24-30
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• 2019

The deck floor of a the cargo truck becomesis damaged and aged due to the continuous loading of the loading cargo and external environmental factors. Floor boards made of wood and metal are often used. In the case of wood, the cost is high due to the use of imported wood, and the strength is easily deterioratesd due to environmental factors. In the case of metal materials, the durability is higher than that of wood, but problems are raised due to the effect of major factors that hinder the weight reduction, and the effects of corrosion. In order to replace this stucturestructural design, this study proposed a wood fiber composite using natural raw materials. Woody composites are being used as environmentally and friendly exterior materials with the combined advantages of plastic, and wood,; low cost and low density. However, due to the nature of the woody composites, the properties are differentdiffer depending on the contents of the matrix, reinforcing agent, additives, compatibilizer, etc. In this study, we investigate these problems through analysis of the microstructure and mechanical properties according to proper content and injection molding conditions. As a result, it is considered that the wood deck composite can replaced the current Deck Floor Boardreplace current deck floor boards through continuous continued research and results of this study.

• 임산에너지
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• 24권2호
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• pp.31-36
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• 2005

꽃송이버섯은 $1,3-{\beta}-D-glucan$의 함량이 다른 버섯에 비하여 훨씬 높은 식용버섯이다. 이 버섯은 항암 및 면역증강 효과가 큰 식용버섯으로 알려지면서 최근에는 일본과 한국에서 재배하고 있다. 하지만, 쉽게 재배할 수 있는 방법이 알려지지 않고 일부 기업이 특허권의 범주 내에서 재배를 하고 있는 형편이다. 본 연구는 이러한 문제를 해결하고자 간단한 공정으로 꽃송이 버섯을 재배 할 수 있는 방법을 개발한 것이다. 낙엽송, 소나무, 잣나무의 톱밥을 이용하여 보릿가루와 설탕을 80:20:3의 중량 비율로 섞은 후 수분함량을 65% 내외로 맞춘 병배지에서 꽃송이버섯을 생산할 수 있었다. 톱밥 종류 및 균주에 따라서 자실체 생산성은 다르게 나타났는데 650g의 배지에서 최고 177g(수율 27%)를 수확할 수 있었다. 따라서 실용적인 꽃송이버섯 재배방법으로 이 배지를 적극 추천한다. 단, 생산성 향상을 위해서는 보릿가루의 적정 농도와 톱밥종류에 맞는 균주의 선발이 지속적으로 필요하다.

• Journal of the Korean Wood Science and Technology
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• 제47권3호
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• pp.299-310
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• 2019

본 연구에서는 목분입자 크기 및 열처리가 목재 셀룰로오스의 결정 특성에 미치는 영향을 검토하기 위하여 형태학적 특성, 셀룰로오스 결정특성, 화학성분분석을 실시하였다. 목분의 색은 열처리 온도가 $100^{\circ}C$에서 $200^{\circ}C$로 높아짐에 따라, 진한 황색에서 진한 갈색을 보였다. 열처리 목재셀룰로오스의 상대결정화도는 목재?에서 200 mesh로 목재의 입자 크기가 작아질수록 낮은 값을 보였으며, 결정폭의 변화는 거의 없었다. 온도가 $100^{\circ}C$에서 $200^{\circ}C$로 증가함에 따라 목재의 상대결정화도가 증가하였고, 결정 폭의 변화는 뚜렷하지 않았다. FT-IR분석 결과, 열처리 온도가 높아짐에 따라 -OH 신축에서 피크가 점차 감소한 것을 확인하였다. $1425cm^{-1}$의 리그닌 C-H 굽힘과, $1370cm^{-1}$의 헤미셀룰로오스 C-H 굽힘은 열처리 온도의 증가에 따른 차이를 보기 어려웠다. $1235cm^{-1}$의 OH-phenolic 신축의 특성 피크와 $1031cm^{-1}$ 부근의 탄수화물의 C-C 신축이 열처리 온도가 높아질수록 감소한 것을 확인할 수 있었다. 결론적으로 목재의 입자크기 및 열처리는 목재 셀룰로오스의 결정특성 변화에 영향을 주는 것이 확인되었다.

• Journal of the Korean Wood Science and Technology
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• 제29권3호
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• pp.59-67
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• 2001

Rice husk flours were analyzed by chemical composition and thermogravimetric methods in nitrogen atmosphere to discuss its feasibility as a raw material for manufacturing agricultural lignocellulosic fiber-thermoplastic polymer composite. It was revealed in the chemical composition analysis that rice husk flour was composed of moisture, 5.0%; lignin, 21.6%; holocellulose, 60.8%; ash, 12.6%. In the thermogravimetric analysis (TGA), thermal decomposition behavior of rice husk flour from room temperature to $350^{\circ}C$ was similar to that of wood flour, but rice husk flour was more thermally stable from 350 to $800^{\circ}C$ than wood flour because of higher silica content in the rice husk flour and smaller particle size of rice husk flour. The activation energy of thermal decomposition was evaluated using Flynn & Wall expression. As the thermal decomposition proceeded in rice husk flour, the activation energy of thermal decomposition appeared almost constant up to ${\alpha}=0.25$, but thereafter increased. Activation energy of thermal decomposition in wood flour, however, decreased steeply up to ${\alpha}=0.3$, but thereafter remained almost constant. From the results, rice husk flour was thought be a substitute for wood flour in manufacturing agricultural lignocellulosic fiber-thermoplastic polymer composite in the aspect of thermal decomposition.

• 한국가구학회지
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• 제26권4호
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• pp.428-434
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• 2015

In this study, we received each wood plastic composites (WPC) from three manufacturers. These WPCs were evaluated regarding their physical and mechanical properties of both before and after accelerated weathering by ultraviolet (UV) irradiation. The total time of exposure of the WPCs to UV irradiation was 1800 h. The water absorption, volumetric swelling and shrinkage of WPCs did not affected by UV irradiation. Among the mechanical properties, there was no significant differences in bending strength and screw withdrawal resistance of UV treated WPCs compared with those of reference WPCs. However, surface hardness of WPCs showed decrease under UV irradiation. Stereoscopic microscopy observation revealed deterioration of the surface layer polymer in all weathered WPCs by UV. Exposure of the WPCs to UV irradiation caused decomposition and disappearance of the polymer layer. From this result, we can estimate that damage of polymer by UV led to a decrease in the surface hardness of the WPCs. The wood flours retained original shape after accelerated weathering by UV irradiation.