• Journal of the Korean Wood Science and Technology
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• v.43 no.3
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• pp.327-333
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• 2015

To measure the dimensional stability of three softwoods by vacuum pressurization of water soluble melamine-formaldehyde (MF) resin impregnation process, properties of resin treated compressed woods (compregs) were measured after impregnating the water soluble MF resin into three coniferous wood species for different impregnation times and resin concentrations. As the resin concentration was higher and impregnation time was longer, coefficients of volumetric shrinkage and anti-volumetric swelling efficiency increased, but coefficients of volumetric swelling, anti-volumetric swelling efficiency and absorption decreased. Also, weight percent gain increased remarkably as the resin concentration was high, but there was no uniform relationship with impregnation time.

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.792-797
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• 2015

In this study, three softwood species were treated with water-soluble melamine resin by different concentration and treatment time under vacuum pressure for improving mechanical property, abrasion resistance, and incombustibility. After the treatment, a compreg was manufactured and then evaluated on physical properties. Additionally, incombustibility of compreg was determined by comparing with a wood that was treated by spraying a water-soluble fire retardant on surface. As concentration of resin increased, bending strength and Brinell hardness increased as well as abrasion resistance, but there was no correlation on treatment and mechanical properties by treatment time. The wood impregnated by water-soluble melamine resin under vacuum pressure showed better incombustibility than that of a water-soluble fire retardant sprayed wood. Therefore, this treatment could be used for improving incombustibility of wood.

• Journal of the Korean Wood Science and Technology
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• v.36 no.4
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• pp.102-108
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• 2008

At the University of Maine, a hemicellulose pre-extraction technology is now being investigated to improve pulp yields, reduce the organic and inorganic load for liquor recovery, and create a feed stream for the generation of new biomaterials. It is important to understand the composition of unextracted wood, extracted wood, and pulping extracts in the design of an economically viable pilot-scale ethanol plant. For analysis of wood pulp composition, the total analytical mass balance closure was 100.6, 100.3, and 81.6% for unextracted chips, extracted chips, and pulping extracts from HPLC-H column analysis. Meanwhile, the total analytical mass balance from the HPLC-P column was 97.8, 86.3, and 80.7%, respectively. This slight variability between H- and P-column results for analytical mass balance may be within the experimental error of the measurement. The data generated by this analysis are important to further design work in commercializing this process.

• Journal of the Korean Wood Science and Technology
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• v.30 no.2
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• pp.158-164
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• 2002

The properties of new porous carbon materials "Woodceramics" are affected by the characteristics of raw boards. To investigate of density profile and resin contents in impregnated boards, control board and 3 types of steam-injected boards were made by steam injection time, The wood species used for manufacturing boards was Sugi(Cryptomeria japonica). The results are as follows: 1) The density gradient of board after 10 minutes steam injection was the smallest and non-steamed board was largest. 2) The resin content and dimensional rise decreased with increase of board density, and were the largest in board after 10minutes steam injection but there was little difference between boards after 5 and 10 minutes steam injection.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.6 s.58
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• pp.106-114
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• 2009

The basis principle of conservation about deterioration and corrosion of cultural assets building is the archetype maintenance, and should not make a factitious damage mistake by repair. Accordingly, conservation processing method using synthetic resins is embossed. The purpose of this paper is about flexural capacity of rectangular section wood using synthetic resins, the 11 specimens are manufactured and made an experiment about reinforcement length, ratio, material strength, direction of synthetic resins as variable. The results of this paper has shown that flexural reinforcement of wood by synthetic resins are efficient and found the possibility of using.

• Journal of the Korean Wood Science and Technology
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• v.32 no.2
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• pp.9-18
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• 2004

This study was carried out to find the efficient methods for preventing resin exudation from spruce board during high temperature environment service.In the dry-air oven test, in-use temperature related to resin exudation of 110℃ could be obtained by the appropriate kiln drying without any special treatment, and the in-use temperature of the radio-frequency/vacuum (RF/V)-dried boards was about 20℃ higher than that of the conventional kiln-dried boards.In the autoclave test, resin exudation was not found from any board dried in the conventional kiln and in the RF/V kiln after the low pressure steam explosion (SE) treating, while for the control resin exudations were more severe in the autoclave test above 130℃ than in the dry-air oven test. It, therefore, would be suggested that resin exudation during high temperature service condition can be prevented more effectively by super-heated steaming green boards than by high-temperature drying boards with low moisture.

• Journal of the Korean Wood Science and Technology
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• v.31 no.5
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• pp.15-22
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• 2003

This study was carried out to investigate the properties of sawdust board impregnated with phenol resin according to the density and resin content of board. The sawdust board were manufactured to target densities of 0.4, 0.5, 0.6, 0.7 g/cm³ and resin content of 5, 10, 15, 20% made from Pinus densiflora S. et Z., Larix. kaemferi C. and Pinus koraiensis S. et Z. The impregnation process were executed in two ways, the application of vacuum pressure then followed by atmospheric pressure, and the application of vacuum pressure with ultrasonic vibration then followed by atmospheric pressure. The density of impregnated sawdust board increased as density and resin content of sawdust board increased, but impregnation rate decreased. The density, impregnation rate, bending strength and brinell hardness of sawdust board in impregnated vacuum pressure with ultrasonic vibration then nonpressure were higher than those of vacuum pressure then nonpressure. In this results, the impregnation rate is increased in vacuum pressure with ultrasonic vibration then nonpressure, it has affected the properties of sawdust board impregnated with phenol resin.

• Journal of the Korean Wood Science and Technology
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• v.33 no.6 s.134
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• pp.17-24
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• 2005

Korean pine (Pinus koraiensis Sieb.et Zucc.) boards of 30 mm thickness were treated by steaming and four different drying methods. Small specimens were taken from the sapwoods of the treated boards and their longitudinal liquid permeability was measured according to Darcy's law. The specimens were also extracted with alcohol and aceton solutions to examine the mechanism of liquid flow in wood. It was observed that specific permeability drastically decreases with measurement time, resulting in violation of Darcy's law. It may be due to that air bubbles formed under vacuum block flow paths in resin canals. The average specific permeabilities of non-extracted and extracted specimens are different from one treatment to another. It is supposed that the properties of residual resin in resin canals change depending on the conditions of treatments. Anatomical examination was conducted with a scanning electron microscope.

• Journal of Korean Association for Spatial Structures
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• v.9 no.3
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• pp.93-100
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• 2009

As interest in latest cultural heritance is increased, an importance about conservation of dilapidated cultural building asset is risen. Most of cultural building asset used wood by main material and conservation repair about corrosion and damage by deterioration of these cultural building asset considers cultural value of member and the basis principle is the archetype maintenance. Accordingly, conservation processing method that use synthetic is embossed. This paper experimented with reinforcement sectional area ratio, direction of section, length, strength of synthetic resins as variable and manufactures total 14 specimens as experimental study about compression reinforcement performance of circular section wood that strengthen by synthetic resins. The result of this paper has shown that adequate strengthen is more efficient than new member and the most important authenticity in strengthen and repair of cultural heritance can be ensured.

• Journal of the Korean Wood Science and Technology
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• v.42 no.1
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• pp.34-40
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• 2014

The effect of neonicochid type wood preservatives on adhesive properties of resorcinol-formaldehyde resin for laminated wood manufacture was examined. By the previous studies, it was verified that the neonicochid type preservative has a high termite-proofing and anti-mold effectiveness. Commercial ACQ (ammoniacal copper quaternary compounds) and CUAZ (copper azol compounds) were used as comparison preservatives of effects on adhesive properties. The wood specimens used japanese red pine (Pinus densifrora) after application with preservatives and then bonded with resorcinol-formaldehyde resin. Adhesive properties were evaluated by shearing strength of adhesive bond and wood failure to dry condition or after accelerated aging test. Of all laminated woods, the wood specimens spread with ACQ or CUAZ showed the lowest shearing strength of adhesive bond. We estimated that the decrease of shearing strength was caused by copper in the ACQ or CUAZ preservatives. On the application of the neonicochid type preservatives, the wood specimens showed the highest shearing strength even after accelerated aging test. From these results, it is concluded that the copper-free neonicochid type preservative not affected the curing of resorcinol-formaldehyde resin.