• Journal of the Korean Wood Science and Technology
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• v.41 no.6
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• pp.490-496
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• 2013

The board using recycled wood waste chip tends to decrease in terms of physical and mechanical properties. The reasons are notably different shape of chips, components of used adhesive and impurity content, which bring the irregular quality and downgrading of board. More over, the board has higher emissivity of formaldehyde than regular board, because recycled chip contains adhesives that were used to make previous products. This low quality of products weakens the price and quality competitiveness, and it led to bringing the issue of problem in Korean board industry. For these reason, in this study, boards using byproducts of plywood were made to evaluate physical and mechanical properties according to manufacturing conditions. As a result, The board was consists of 4~16 mesh chips for core layer and veneer on both face and they were combined using EMDI, and its' bending strength was 57.7 $N/mm^2$ which is 215% higher than that of OSB (26.8 $N/mm^2$). Moreover, the emissivity of formaldehyde was 0.7 ppm, this board seems to substitute OSB for rated sheathing.

• Journal of the Korean Wood Science and Technology
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• v.50 no.2
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• pp.104-112
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• 2022

Indoor air quality is a very important environmental factor in modern society. However, air pollutants generated from various interior construction materials significantly affect the human body, including formaldehyde (HCHO) and volatile organic compounds that threaten public health by deteriorating indoor air quality. Effective in removing these harmful substances are porous materials, such as woodceramics. In this study, charcoal, a porous material, was added to rice husk, an agricultural by-product, and sawdust generated during the sawing process to prepare boards and ceramics at different mixing ratios, and the HCHO deodorization performance and far-infrared emission characteristics were measured. As the mixing ratio of charcoal increased, the deodorization rate of the boards and ceramics tended to increase. Overall, the deodorization rate was measured to be 80% to 90%, indicating that the boards and ceramics prepared with charcoal are suitable to be used for the purpose of deodorization. The effect of the material mixing ratio on far-infrared emissivity and emission power was insignificant.

• Journal of the Korea Institute of Building Construction
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• v.13 no.3
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• pp.253-262
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• 2013

The test on the mix of PVA fiber of low carbon inorganic composite as a cement substitute found it to be satisfactory in terms of flexibility and stiffness. The result of the evaluation of the properties of low carbon inorganic panel revealed that the absorptivity was low at 8 to 9%, which is lower than the KS value of 25%. Also, the test on non-combustibility and gas toxicity found that these factors satisfied the decision criteria. In the test on heavy metals discharges, Pb, Cd, Cr6+, Hg, and As were not detected. Regarding far-Infrared emissivity and formaldehyde emission, the substitute was found to be harmless to the human body. Therefore, if the issue of shrinkage, which is a disadvantage of inorganic composites, is addressed, it is judged that it is possible to develop a low carbon inorganic composite panel with better performance.

• Korean Journal of Agricultural Science
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• v.36 no.1
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• pp.19-25
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• 2009

This study was carried for recycling laminated PB and MDF of disused furniture. PB and MDF particles taken from disused furniture were heat-treated at $250^{\circ}C$ and four levels of treatment time, 2, 4, 6 and 8 hours. The recycled boards were made with heat-treated particles after milling and screening with 100 mesh. The bending strength of the recycled boards were lower than that of virgin boards while their anti-swelling efficiency were much improved. Their formaldehyde emissivity were very low. Thus it was concluded that the recylcled boards are prospective environment-friendly material for interial consturction.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.593-596
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• 2006

The environment-friendly building material, photocatalyst/scoria/loess concrete, was prepared using scoria and loess (which have merits as building materials) and photocatalyst (which has the functions to compose the environmental contaminants and of self cleaning). In order to apply this material as a building material, the compressive and flexible strengths, and water absorptivity (which have been set by Korea Industrial Standard) were measured. In order to know the environment-friendly characteristics of this material, several tests, such as, the tests of emissivity and emission power of far infrared ray and acoustic absorptivity, antibacterial test for Escherichia coli and Pseudomonas aeruginosa, antifungal test for mixed fungal strains, and deodorization test of ammonia were carried out. Moreover, the removal characteristics of NOx, and formaldehyde (HCHO) by photocatalyst/scoria/loess concrete were examined as the following different parameters: the removal characteristics of these contaminants with the substitution ratio and the kind of photocatalyst, light source, UV intensity of sunlight, relative humidity, intial NOx concentration.

• Journal of the Korean Wood Science and Technology
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• v.45 no.5
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• pp.580-587
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• 2017

Woodfiber insulation board can be considered as a one of the key material for low energy consumption, comfortable and safety construction of residential space because of its eco-friendly and high thermal insulation performance. This study was carried out to investigate the formaldehyde (HCHO) total volatile organic compounds (TVOC) emission properties and combustion shapes by flame test of low density fiberboards (LDFs) prepared with different adhesives. HCHO TVOC emission and combustion properties of LDFs prepared by melamine urea formaldehyde (MUF), phenol formaldehyde (PF), emulsified methylene diphenyl diisocyanate (eMDI) and latex resin adhesives were measured by desiccator method, 20 L chamber method, and flame test, respectively. As results, LDFs manufactured by MUF, eMDI and latex resin adhesives satisfied the Super $E_0$ grade of HCHO emission performance except PF resin. Furthermore, TVOC emission of all LDFs were satisfied the Korean indoor air quality standard (below $400{\mu}g/m^2{\cdot}h$). Especially, LDF with eMDI resin adhesive showed the lowest HCHO and TVOC emissivity, that $0.14mg/{\ell}$, $12{\mu}g/m^2{\cdot}h$, respectively. However, eMDI emitted the small amount ($3{\mu}g/m^2{\cdot}h$) of toluene in VOC components. In the flame test, LDF with MUF resin adhesives showed the most favorable shape after flame test compare to LDFs prepared other adhesives. Based on HCHO and TVOC emission, and combustion shapes, MUF resin adhesive may be recommended to prepare LDF for insulation purpose.