• Proceedings of the KAIS Fall Conference
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• 2004.11a
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• pp.296-298
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• 2004

본 연구에서는 압출성형에서 Nylon6 를 기재로 멜라민계 난연제를 사용하여 난연성 및 물성평가를 비교, 분석하였다. 멜라민계 난연제를 선택한 이유는 탈할로겐화 추세에 일조를 하며 연기가 적고, 생분해를 하는 물질이기 때문에 큰 장점이 있다. 또한 새로운 제품 및 적용범위를 발굴하기가 상대적으로 용이하다는 장점이 있기 때문에 멜라민계 난연제를 선택하였다. 난연 Test는 UL-94 측정방법을 이용하였고 물성평가는 UTM 측정기기로 인장강도, 연신율, 굴곡강도, 굴곡탄성율 측정하였다. 또 충격강도 시험기로 충격강도를 측정하였고, 물성평가 경우에는 난연제로 인한 물성저하를 최소화 하기위해 Nano-clay 를 첨가하여 비교하였다. 연구결과는 난연 Test 경우 난연제의 함량이 $5wt\%$ 이상이면 V0급으로 나왔고 물성평가에서는 Nanoclay를 첨가한 실험이 물성저하를 대처할 수 있을 정도의 결과로 보여 진다.

• Journal of the Korea Furniture Society
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• v.23 no.4
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• pp.355-363
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• 2012

From the end of the 20th century, there has been increased interest for life Well-Being and LOHAS. Attracting the interest of consumers for eco-friendly materials, the furniture in the finish of the interior space of interest. In the finish of the interior space and living furniture, eco-friendly materials and the process of development and research has led to a surface treatment for reducing hazardous substances. By a combination of natural materials and the latest eco-friendly rating, recognized in LPM (Low Pressure Melamine) has been developed. LPM was used birch and eco-friendly materials, the development of student furniture can be expanded depending on the growth.

• Textile Coloration and Finishing
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• v.9 no.6
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• pp.68-73
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• 1997

Urea/formaldehyde(UF) and melamine/formaldehyde(MF) microcapsules containing perfume and 2,4,4'-trichlroro-2-hydroxydiphenyl ether(DP) were prepared by the in-situ polymerization using urea and formaldehyde. Effects of dispersing agent, accelerating agent, formaldehyde, agitation speed on the mean diameter of microcapsules were investigated. The diameter of microcapsule was decreased with increasing dispersing agent concentration. A slight increase in the diameter was observed when the concentration of film forming material was increased. The diameter of microcapsule was decreased with increasing agitation speed up to 8,000rpm. The mean diameters of UF microcapsule prepared at 8,000rpm are about 3$\mu$m. A slight decrease in the diameter was observed when the concentration of resorcinol was increased.

• Journal of the Korean Applied Science and Technology
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• v.18 no.1
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• pp.40-48
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• 2001

Curing reaction was carried out with the acrylic resin (ACR) [n-butyl acrylate/atyrene/2-hydroxyethyl methacrylate/acetoacetoxyethyl methacrylate (AAEM)] synthesized before and a curing agent, hexamethoxymethylmelamine (HMMM). With rotational rheometer, the effect of catalysts on curing rate of acrylic resin/melamine was examined. Among the four catalysts used, p-toluene sulfonic acid showed the highest reactivity, and the optimum amount of catalyst was 0.5 phr. It was observed that in the ACR/HMMM curing reaction, gelation point was lowered with the increasing the amount of AAEM and HMMM in the ACR.

• Korean Journal of Chemical Engineering
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• v.35 no.12
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• pp.2468-2473
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• 2018

Nitrogen-doped activated carbon fibers (ACFs) were prepared by chemical vapor deposition using melamine powder and acetonitrile for introducing quaternary nitrogen on the commercial ACFs, subsequently heated at $950^{\circ}C$ and activated by steam. Adsorption experiments of nitrate in aqueous solution were also conducted to evaluate adsorption capacity of the prepared ACFs using ion chromatography. The amount of introduced nitrogen content and nitrogen species on activated carbon fibers was examined by CHN elemental analyzer and X-ray photoelectron spectroscopy, respectively. As a result, adsorption capacity of quaternary nitrogen-doped ACF (ST-ML-AN-ST) was 0.75 mmol/g, indicating ca. two-times higher than that of untreated ACF (0.38 mmol/g). According to the adsorption data, the Langmuir isotherm model was the best fit. The prepared samples were also regenerated using hydrochloric acid. After regeneration, the adsorption capacity of the nitrogen-doped ACF (ST-ML-AN-ST) showed ca. 80% on average, implying that a portion of nitrates was adsorbed on the prepared ACFs irreversibly.

• Journal of the Korean Wood Science and Technology
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• v.51 no.1
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• pp.14-22
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• 2023

Economical use of larix (larch) boards (grade 3) in industries is lower than that of imported hardwood; thus, studies have been conducted toward performance improvement of larix boards. Herein, flexural modulus of larix board samples laminated with wood adhesives polyurethane resins, poly (vinyl acetate) resins, phenol-resorcinol-formaldehyde resins, melamine-formaldehyde resins, and urea-formaldehyde resins was compared with that of the samples bonded with adhesives reinforced with mesh-type basalt fibers. Moreover, the flexural moduli of the laminated samples bonded by mesh-type basalt fibers were compared with those of reinforced samples. The results showed that boards laminated with polyurethane and urea-formaldehyde resin adhesives had higher flexural modulus than those without the lamination. In particular, the increase in the flexural modulus was relatively significant for the 2- and 3-ply board structures laminated with polyurethane adhesives compared to those with reinforcement. The 3-ply board structure without reinforcement had the highest flexural modulus when the urea-formaldehyde resin adhesive was used.

• Korean Chemical Engineering Research
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• v.61 no.4
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• pp.635-644
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• 2023

Due to the rapid development of the livestock industry, particularly due to residual pharmaceutical antibiotics, environmental populations have been negatively affected. Herein, we report a ZnO/melamine-functionalized carboxylic-rich graphene oxide (ZFG) photocatalyst for visible light-driven photocatalytic degradation of tetracycline hydrochloride in aqueous solutions. The properties of the photocatalysts were evaluated by XRD, FTIR, XPS, Fe-SEM, HR-TEM, TGA, Raman spectroscopy, UV-Vis spectroscopy, zeta potential, and electrochemical measurements. The photocatalytic activity was measured using high-performance liquid chromatography. The photocatalytic properties of the ZFG photocatalyst evaluated against the tetracycline hydrochloride (TCH) antibiotic under visible light irradiation showed superior photodegradation of 96.27% within 60 min at an initial pH of 11. The enhancement of photocatalytic degradation was due to the introduction of functionalized graphene, which increases the light-harvesting capability and molecular adsorption capability in addition to minimizing the recombination rate of photogenerated charge carriers due to its role as an electron acceptor and mediator.

• Journal of Forest and Environmental Science
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• v.3 no.1
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• pp.11-16
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• 1983

Two species which belong to a needle-leaf tree, three species which belong to a broad-leaved tree and three resins were selected and made into samples. They were glued in the amount of spread-$200g/m^2$, clamping pressure-$10kg/cm^2$ and room temperature during 48 hrs. This experiment was carried out to investigate results on gluing faculty tests with examining block shear strength, wood failure, tensile strength and bending strength. The result obtained may be summarized as follows. 1. Strength values of each resin made not difference, but those of each species had difference. 2. The result which Picea Koraiensis Nakai had good wood failure reveals better resin strength than wood strength. 3. Pinus Koreaiensis sieb. et Zucc. had poor tensile strength regardless of resins. 4. A broad-leaf tree, Robinia pseudoacacia Linne had good bending strength.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.1
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• pp.33-40
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• 2013

The cement industry brought very severe environment problems with massive carbon dioxide during its production. To solve this problem, attempts on Alkali-Activated Slag (AAS) concrete that perfectly substitutes industrial by-products such as ground granulated blast furnace slag (GGBFS) for cement are being actively made. AAS concrete is possible to have high strength development at room temperature, however, it is difficult to ensure the working time due to the fast setting time and the loss of workabillity because of the alkali reaction. In this study, the early age properties of alkali activated slag mortar are investigated to obtain the fundamental data for AAS concrete application to structural members. The water-binder ratio (W/B) was fixed at 0.35 and sodium hydroxide and waterglass as alkali activator was used. The compressive strength, the flow and the ultrasonic pulse velocity were measured according to the type of superplasticisers, which were naphthalene(N), lignin(L), melamine(M) and PC(P), up to a maximum of 2 percent by the mass of GGBFS. The results showed that adding melamine type of superplasticizer improved the fluidity of AAS mortar without decreasing the compressive strength, while naphthalene and polycarbonate type of superplasticizer had little effect on the fluidity of AAS mortar.

• Composites Research
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• v.28 no.5
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• pp.316-321
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• 2015

This study investigated the effects of microcapsules on mechanical properties and thermal stability of the composite material containing self-healing microcapsules. To this end, tensile specimens and flexural specimens containing melamine-urea-formaldehyde (M-U-F) shell walled microcapsules with diameters of $70{\sim}130{\mu}m$ were manufactured. Varying amount of microcapsules in the specimens was considered: 0 wt%, 0.5 wt%, and 1.0 wt%. The tensile and flexural tests were conducted to evaluate mechanical properties of the specimens containing the microcapsules and the thermogravimetric analysis test was performed to evaluate the thermal stability of the specimens containing the microcapsules. The results show that the tensile strength of the specimens was sensitive to the amount of the microcapsules compared to the tensile modulus even though the tensile modulus of the specimens was not significantly affected by the amount of the microcapsules. However, reduction of the tensile strength was not linearly proportional to the amount of microcapsules; similar results were observed in the flexural test. The weight changes of the specimens containing the microcapsules, as a function of temperature, were similar to those specimens without microcapsules. The thermal stability of the specimens was not affected significantly by the microcapsules embedded in the specimens.