• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.4
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• pp.32-42
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• 2012

Wood biomass including forest residues, waste wood, and construction residuals has been widely generated in Korea, but forest biomass from the National Forest Management Operation Project plays a big role in generating wood biomass. Unfortunately the promotion policy of woody energy organized by the Forest Service in Korea concentrates more on demand creation rather than on supply expansion. Therefore, in order to utilize insufficient wood resources effectively, it is greatly required to develop uses for maximizing their added value. In particular, more attention to the use of the second generation biomass has been paid in foreign countries because there is a threshold that the first generation biomass cannot produce enough biofuel without threatening food supplies and biodiversity. In Korea, wood pellets are regarded as the alternative clean fuels to oils and coals that emit green house gases into the atmosphere. However, using wood as pellet raw materials can not be an economic way because the value of wood disappears right after burning in the boiler in spite of its contribution to the decrease of carbon emission. Differently from wood pellets, kraft pulping process using woody biomass produces black liquor as a by-product which can be used to generate electricity, bioenergy and biochemicals through gasification. Thus, it can be more economical to make a torrefaction of lignocellulosic biomass such as low-quality wood and agricultural leftovers as raw materials of pellets.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.38 no.4 s.117
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• pp.68-75
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• 2006

Electromagnetic shielding sheet using the carbon and wood fiber mixture was manufactured in an effort to develop an electromagnetic shielding packaging material. Carbon fibers were cut into 5, 10, and 15 mm using the automatic cutting device and blown and dispersed using compression air passed through the fine nozzle. Then carbon fibers were slurried with water (0.1% consistency), and softwood kraft pulp along with cone starch were added. The wet mats were manufactured by dewatering in modified hand-sheet machine. The wet mats were pressed upto $4kgf/cm^2$ in the carbon and wood fiber mixture mat press. The wet mats were dried in the automatic controlled plate dryer. Investigation on the formation and surface structure of the newly developed carbon and wood fiber mixture electromagnetic shielding sheet were carried out using the scanning electron microscopy and the image analyzer. Finally electromagnetic shielding characteristics of the newly developed carbon and wood mixture sheet were measured using net-work analyser. The result was promising in the light of the fact that this method could open a new way to substitute the expensive imported electromagnetic shielding sheet.

• Journal of the Korean Society of Safety
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• v.27 no.1
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• pp.26-31
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• 2012

Wood-plastic composites represents a growing class of materials used by the residential construction industry and furniture industry. In this study, the effect of flame retardants on the flammability and mechanical properties of wood flour-high density polyethylene(HDPE) composites were studied. we were manufactured wood flour-HDPE composites by modular intermeshing co-rotating twin screw extruder with L/D ratio of 42. The flame retardant properties were used limiting oxygen index(LOI) and mechanical properties were measured by universal testing machine(UTM). The Morphological analysis of composites were analyzed by Scanning electron microscope(SEM). It was found that Ammonium polyphosphate can effectively reduce the flammability of the wood flour-HDPE composites. Marginal reduction in the mechanical properties of the composites was found with addition of flame retardants. SEM images showed that the coupling agent improved wood flour-HDPE interfacial bonding.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06a
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• pp.43-49
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• 2006

The surface and pore structure of cellulose fibers have a significant impact on the properties and performance in applications. Cellulase enzymatic hydrolysis of cellulose fibers can result in changes to the surface and pore structure thus providing a useful tool for fiber modification. This research characterizes these changes using various test methods such as fiber dimension, water retention value, hard-to-remove water content, freezing and non-freezing bound water content, polymer adsorption, and crystallinity index. For a high-dosage enzyme treatment (0.10 g/g), the fiber length was significantly decreased and the fibers were 'cut' in the cross direction, not in the axial direction. The swelling capacities as measured by the WRV and HR water content increased for the high-dosage treatment. Three independent measurements (non-freezing bound water, polymer adsorption, and crystallinity index) are in good agreement with the statement that the amorphous regions of cellulose fibers are a more readily available substrate relative to crystalline regions. Based on the experimental results obtained herein, a model was proposed to explain surface and pore structure modification of cellulose fibers via enzymatic treatment.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.1
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• pp.1-10
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• 2011

To investigate the combination dyeing properties of natural dyes, the combination dyeing using gallnut,-Al, Cu, Fe-sappan wood, and gallnut-Al, Cu, Fe-gardenia was performed on bast fiber of mulberry, cotton, silk, and their K/S values, colors, and sunlight fastness were measured. The gallnut-Al, Cu, Fe-gardenia dyeing showed the highest K/S values when the dyeing concentration of gallnut is 3%. It tended to show the higher K/S values than gallnut-Al, Cu, Fe-sappan wood. The silk showed the highest values of in K/S, and then followed by cotton, and bast fiber of mulberry. The mordants developed different colors on the bast fiber and the cotton treated with gallnut-Al, Cu, Fe-sappan wood. However, the silk showed a series of YR, showing no effect of the mordants on the development of color. The combination dyeing of gallnut-Al, Cu, Fe-gardenia showed a series of Y. The results showed that sappan wood could develop various colors but gardenia could develop a series of Y. No distinct improvement on sunlight fastness of the combination dyeing was observed.

• Journal of the Korean Wood Science and Technology
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• v.50 no.3
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• pp.167-178
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• 2022

To investigate the influence of manufacturing environment on bonding performance of mixed cross laminated wood (CLT) using polyurethane (PUR) adhesive, a boiling water soak delamination test according to the temperature and relative humidity was conducted. The 5-ply mixed CLT consisted of Japanese Larch for external and middle layer and yellow poplar for internal layer. The PUR adhesives with different opening times of 10 and 30 minutes were used. The mixed CLT was manufactured according to pressing times of PUR and manufacturing environments of summer and winter. In case of summer environment, the delamination rate of the mixed CLT with pressing time of 4 hours using a PUR adhesive with open time of 10 minutes met the requirements of KS F 2081. In case of winter environment, the delamination rate of the mixed CLT didn't meet the requirements of KS standard. However, it was possible to confirm the effect of improving the adhesive performance by adjusting the pressing time according to the open time of the adhesive under the manufacturing conditions. The delamination rate of CLT with open time 30 minutes PUR, manufactured by indirect moisture supply methods was 11.2% better than direct moisture supply methods. As a result of delamination test in the same condition of relative humidity and adhesive, it was found that the temperature of manufacturing environment influences the adhesive performance.

• Fashion & Textile Research Journal
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• v.11 no.6
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• pp.968-973
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• 2009

To get a variety of colors on silk fabrics with natural dyes, mordanting and combination dyeing were carried out. Gromwell, sappan wood, safflower were used as the three primary colors for combination dyeing. Metal compounds containing alum and iron were used as mordanting agents. In combination dyeing of safflower and sappan wood, safflower and gromwell, gromwell and sappan wood, various colors were obtained according to the content of dyes used. Safflower/sappan wood dyeing showed different colors between yellow red and red purple of Munsell color circle such a YR, R and RP. And safflower/gromwell dyeing showed R, RP, P and PB Munsell color circle and then gromwell/sappan wood showed R, RP and P. As the result of these experiments, wide range of colors (YR-R-RP-P-PB-B) were obtained according to various mixing portion of safflower, gromwell, sappan wood, dyebath pH and repetition dyeing.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.2
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• pp.47-54
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• 2009

Anatomical characteristics of kenaf were investigated in transverse, radial and tangential direction by optical and scanning electron micrograph. Kenaf was made up of bast fibers, wood fibers, vessels and parenchyma cells. Bast fibers were long slender cells with different types of pits. The shape of wood fibers were in various ways and pointed at the ends. The pits were observed on the surface of bast fibers. Kenafs were diffuse and radial porous. and composed of solitary pores and two or three radial pore multiples. Various types of vessels were observed. The pits showed alternate pitting and larger diameter than other cells. Parenchyma cells were rectangular or square with different shapes of pith parenchyma cells compared to conventional types of parenchyma cells in wood. The number of pith on the surfaces were small.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.4
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• pp.102-108
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• 2015

Agricultural cultivation papers treated with water repellent were investigated in order to analyse mechanical properties and durability. The water repellency was optimal when papers are treated with Wb and Sa water repellents. Also, WCPs with 5% water repellent were more effective than those of 3 and 10%. In addition, water repellency of WCPs with Wb and Sa water repellents were kept constant in correlation with aging time. Finally, WCP with Wb water repellent possesses efficiency in terms of mechanical properties and durability.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2003.11a
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• pp.17-26
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• 2003

Nalita wood(Trema orientalis) is one of the fastest growing woods in the world. It may be a viable species for pulpwood. The physical, chemical and morphological properties of Nalita were studied. The total lignin, pentosan and holocellulose content in Nalita wood were 24.7%, 22% and 81.2%, respectively. Its fiber length was about 0.92 mm, which are comparable to Acacia mangium. Nitrobenzene oxidation of Nalita wood meal indicated that the guaciayl and syringyl unit were the major constituent of Nalita lignin. Nalita produced 50% pulp yield at Kappa number 21 in soda-anthraquinone process. The strength properties of Nalita pulp were comparable to other tropical hardwood pulp. At $40_{\circ}$ SR, the breaking length, burst index, tear index and total energy absorption were 6000 m, $3.5kPa{\cdot}m^2/g\;and\;7.0mN{\cdot}m^2/g\;and\;75J/m^2$, respectively.