• Journal of the Korean Wood Science and Technology
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• v.22 no.1
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• pp.44-53
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• 1994

This research was carried out to investigate the effect of paper sludge addition on formaldehyde emission, and physical and mechanical properties of UF-particleboard. In order to investigate the effect of paper sludge addition to resin, particleboards were bonded with urea-formaldehyde resins containing 5, 10, 15% paper sludge powders of three types(A Type: -200 mesh, B Type: -100~+200 mesh. C Type: -50~+100 mesh), based on weight of resin solid. Also the effect of paper sludge addition to furnish was studied from particleboards fabricated with ratios of sludge to particle of 5:95, 10:90, 15:85 based on oven-dry weight. Tests were conducted on the manufactured particleboards to determine formaldehyde emission, bending properties, internal bond strength and thickness swelling. The obtained results were summarized as follows: The addition of paper sludge powder to resin yielded a higher pH of cured resin. Formaldehyde emission decreased with the increase of paper sludge powder addition to resin and paper sludge composition ratio to furnish. Particleboard bonded with urea-formaldehyde resin containing paper sludge powder and particleboard mixed with paper sludge have similar bending properties(MOR, MOE) and thickness swelling compared with control particleboard. Internal bond strength of particleboards treated with paper sludge were lower than that of control particleboard. The use of paper sludge as scavenger was achieved reduction of formaldehyde emission without depression of physical and mechanical properties of particleboard. Also the use of paper sludge was able to concluded that there is possibility of partial substitution of wood particle materials.

• Journal of the Korea Furniture Society
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• v.11 no.2
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• pp.73-78
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• 2000

This study was carried out to measure formaldehyde emission with the passing of two years from plywood, sliver-board and strand-board bonded with urea resins which were made of 6 f/U molar ratios. The urea resins were manufactured by six kinds of formaldehyde/urea molar ratio of 1.0, 1.2, 1.4, 1.6, 1.8 and 2.0. 1. The plywood with molar ratio of 1.0 satisfied the KS F3101 $F_2$ directly after manufacture. The plywood with molar ratio of 1.2 satisfied m 3 days. The plywood with molar ratio of 1.4 satisfied the $F_3$ in 3 days and the $F_2$ in 600 days. And the plywood with molar ratio of 1.8 and 2.0 satisfied the $F_3$ in 365 days, but didn't satisfy the $F_2$ in 730 days. 2. Sliver-board with molar ratio of 1.0 and 1.2 satisfied the KS F3104 $E_2$ right after manufacture. Sliver-board with molar ratio of 1.4 and 1.6 satisfied in 150 and 360 days, respectively. Sliver-board with molar ratio of 1.8 and 2.0 satisfied in 730 days. 3. Strand-board with molar ratio of 1.0 and 1.2 satisfied the KS F3104$ E_2$ directly after manufacture. Strand-board with molar ratio of 1.4 and 1.6 satisfied in 150 days. But Strand-board with molar ratio of 1.8 and 2.0 didn't satisfied in 730 days.

• Journal of the Korean Wood Science and Technology
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• v.35 no.6
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• pp.100-107
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• 2007

People have spent lots of time inside building about 90% of these day. Industry has been developed rapidly after I960. Construction materials had changed from natural materials to chemical materials and confidentiality of building has been more higher than before by policy of saving energy. These have caused sick-building syndrome (SBS) for us. So people want environmental construction materials for their house. We designed a environmental loess (yellow soil) finishing material which was composed of loess, water, water-soluble resin, hardener and filler. The purposes of this study were that making an environmental loess finishing material with optimum ratio, evaluating the usability of loess finishing material for wall. Furthermore it was suitable for wall to evaluate mechanical properties that are impact test, cracking test, abrasion test and de-bonding test, environmental properties that were emission of VOCs, formaldehyde and far infrared radiation.

• Journal of the Korean Wood Science and Technology
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• v.30 no.1
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• pp.11-17
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• 2002

This study was performed to determine the characteristics of particleboard made from three-months-old bamboo, (Phyllostachys nigra var henonis Stapf) grown in Damyang district, Korea. Total 60 particleboards were manufactured with 1% of liquid wax emulsion using urea-formaldehyde resin content 9%,11% and 13%, respectively. The particle boards consisted of three layers, in which face layer had the same proportion of a weight 25% of the particleboard each. And the core layer had a weight 50% of the board. The core layer and face layer had the particle dimension passing 6 mesh (3.35 mm), 12 mesh (1.70 mm), respectively. The study was carried out to determine the effect of the growing time of 3 months and 3 years on particleboard properties. The physical and mechanical properties of boards were measured and compared to the Korean standard (KS) requirements of particle boards. The results were as follows; 1. The longer the growing time, the higher the density of bamboo. Density of the upper part of bamboo showed higher than that of lower part. 2. Density and moisture content of the two particle boards did not show significant differences. Three-months-old bamboo particleboard gave higher thickness swelling than three-years-old bamboo particleboard. Bamboo particleboard passed the thickness swelling test of KS. 3. The static bending and internal bond strength of three-months-old bamboo particleboard were higher than those of three-years-old bamboo. Increase of resin contents in bamboo particleboard increased bending and internal bond strength, proportionally. Strength properties of bamboo particle board were above KS. 4. Formaldehyde emission of all the bamboo particleboards satisfied E₂ level (5.0 mg/L) of KS F 3104.

• Korean Chemical Engineering Research
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• v.56 no.4
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• pp.577-584
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• 2018

This study was conducted to investigate the potential of chicken feather (CF), which is a by-product in poultry industry, as a partial substitute of wood fiber in the production of wood-based fiberboard. Keratin-type protein constituted the majority of CF, and its appearance did not differ from that of wood fiber. When the formaldehyde (HCHO) adsorptivities of CF compared by its pretreatment type, feather meal (FM), which was pretreated CF with high temperature and pressure and then grounded, showed the highest HCHO adsorptivity. In addition, there was no difference between the adsorbed HCHO amounts, which was measured by dinitrophenylhydrazine method, of scissors-chopped CF and CF beated with an electrical blender. Mechanical properties and HCHO emission of medium-density fiberboards (MDF), which were fabricated with wood fiber and 5 wt% CF, beated CF or FM based on the oven-dried weight of wood fiber, were not influenced by the pretreatment type of CF. However, when the values compared with those of MDF made with just wood fiber, thickness swelling and HCHO emission of the MDF were improved greatly with the addition of CF, beated CF or FM. Based on the results, it might be possible to produce MDF with improved dimensional stability and low HCHO emission if CF, beated CF or FM is added partially as a substitute of wood fiber in the manufacturing process of MDF produced with the conventional urea-formaldehyde resin of $E_1$ grade. However, the use of CF or FM in the production of MDF has a low economic feasibility at the current situation due to the securing difficulty and high cost of CF. In order to enhance the economic feasibility, it requires to use CF produced at small to medium-sized chicken meat plants. More importantly, it is considered that the technology developed from this research has a great potential to make provision for the prohibition of animal-based feed and to dispose environmentally avian influenza-infected poultry.