• Title/Summary/Keyword: melamine

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Preparation and characterization of Melamine-Formaldehyde Resin Microcapsules Containing Fragrant Oil

  • Hwang, Jun-Seok;Kim, Jin-Nam;Wee, Young-Jung;Yun, Jong-Sun;Jang, Hong-Gi;Kim, Sun-Ho;Ryu, Hwa-Won
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.11 no.4
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    • pp.332-336
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    • 2006
  • In this study, melamine-formaldehyde microcapsules were prepared via in situ polymerization using peppermint oil as a core material, melamine-formaldehyde as the wall material, Tween 20 as the emulsifier, and poly (vinyl alcohol) as a protective colloid. The melamine-formaldehyde microcapsules prepared in this study were then evaluated with regard to their structures, thermal properties, particle size distributions, morphologies, and release behaviors.

Mini-review; Melamine-related Urinary Stone Disease (Mini-review: 멜라민에 의한 신요로계 결석)

  • Kang, Hee-Gyung
    • Childhood Kidney Diseases
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    • v.13 no.1
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    • pp.21-25
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    • 2009
  • Last year, an epidemic of infantile urinary stone disease developed in China. Investigation revealed that melamine-tainted diary product caused urinary stone in these infants. Young infants were susceptible to the melamine toxicity and dehydration or other stone-prone factors aggravated the toxicity. Melamine-related urinary stones were small, multiple, and mainly composed of uric acid, thus conservative treatment of hydration and urine alkalinization worked well in majority of the patients.

Water Repellent Finish for Divided Type PET/Nylon Fabrics with Fluoro Alkyl Resin (불소수지를 이용한 분할형 PET/nylon 직물의 발수가공)

  • Lee, Bang One;Pak, Pyong Ki;Cheong, Yun Suk;Lee, Hwa Sun
    • Textile Coloration and Finishing
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    • v.9 no.4
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    • pp.1-6
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    • 1997
  • Water repellent finish was carried out using water repellent agent(AG-480), melamine resin(Sumitex Resin MK), and catalyst(Sumitex Accelerator ACX). PET/nylon fabrics were treated with melamine resin by pad-dry-cure method and subsequently washed and dried. Durable water repellency was controlled by the melamine resin and catalyst. Water repellency was tested by spray rating method and durability of water repellency were measured by launder-O-meter and pilling tester. The optimum conditions of durable water repellent finish for new synthetic fabric were as follows; concentration of water repellent finishing agent 20g/l; concentration of melamine & catalyst 0.5g/l; curing condition $160^{\circ}$ ${\times}$ 30sec. Water repellency after washing and rubbing is improved by melamine resin and catalyst.

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A Study on the Sericin Fixation of Raw Silk Fibers by Fixing with the Mixtures of Various Amines and Formalin (아민류와 포르말린 혼합액에 의한 실크 생사의 세리신 정착에 관한 연구)

  • Park, Geon-Yong
    • Textile Coloration and Finishing
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    • v.21 no.1
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    • pp.67-72
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    • 2009
  • To investigate the strong and effective sericin fixing agents and conditions, raw silk fibers were treated with the mixtures of urea-formalin, thiourea-formalin and melamine-formalin as sericin fixing agents, respectively. And the treated raw silk fibers were degummed by the degumming liquors of alkaline detergent and sodium carbonate to confirm the hardness of sericin fixation. The weight of raw silk fibers was decreased in the process of sericin fixation treating at 80$^{\circ}C$ for 60min. The effective sericin fixation was obtained by treating at $60{\sim}80^{\circ}C$ for 15min with the mixture of melamine and formalin. The mixture of melamine and formalin showed an outstanding ability of sericin fixation because the three amino groups of melamine were able to cross-link the hydroxy amino acids of sericin such as serine with the assistance of formalin.

Analysis of Melamine and Cyanuric Acid in Cigarette Mainstream Using GC/MS (GC/MS를 이용한 담배연기중 Melamine과 Cyanuric Acid 분석)

  • Kwak, Ho-Geun;Lee, Soo-Hyun;Lim, Heung-Bin
    • Journal of the Korean Society of Tobacco Science
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    • v.31 no.2
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    • pp.107-114
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    • 2009
  • In this study, we investigated the existence of melamine and cyanuric acid in cigarette smoke because leaf tobacco contains lots of nitrogen compounds and they are capable of pyrolytic synthesis while smoking. The extraction and derivatization conditions of two compounds were performed according to the procedure of U.S. Food and Drug Administration(FDA). Ky3R4F as reference cigarette was smoked on ISO condition(Puff volumne : 35 ml, duration : 60 sec, Interval : 2 sec). Compared with the results Ky3R4F and standard solution, retention time of two compounds was not corresponded. As a result, we concluded that melamine and cyanuric acid were not existed in cigarette smoke.

Effects of Urea-Phenol-Melamine Copolymer Adhesive on the Plywood Qualities (요소(尿素)·멜라민·페놀공축합수지(共縮合樹脂)가 합판(合板)의 재질(材質)에 미치는 영향(影響))

  • Lee, Hwa-Hyoung;Hong, Seung-Do
    • Journal of the Korean Wood Science and Technology
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    • v.12 no.1
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    • pp.38-43
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    • 1984
  • Water soluble urea-melamine-phenol copolymer adhesive manufactured with 80 percent of urea resin contents was manufactured by different molar ratio for a high temperature curing type, and their properties and strengthes were examined through manufactures of plywood with Kapur (Dryobalanops spp.) veneers. The results are summarized as follows: 1. Specific gravities of air dried plywood manufactured from each adhesive ranged from 0.78 to 0.84 and their moisture contents met the KS requirement. 2. In dry and wet shear strength, $U_{80}M_{10}P_{10}$ copolymer resin showed the highest value and urea resin was the lowest, indicating that melamine and phenol were effective for increasing glue shear strength of urea resin. 3. In case of glue shear strength after boiling test, phenolic resin was the nest and melamine was not so effective as phenol on reinforcement of boiling water resistance of urea resin.

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A Method of Measuring Wood Failure Percentage of Wood Specimens Bonded with Melamine-Urea-Formaldehyde Resins Using I mage Analysis

  • KIM, Minseok;PARK, Byung-Dae
    • Journal of the Korean Wood Science and Technology
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    • v.49 no.3
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    • pp.274-282
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    • 2021
  • Transparent and colorless melamine-urea-formaldehyde (MUF) resins make it difficult to identify the area of wood failure percentage (WFP) in the fracture surface of bonded wood specimens. Therefore, in this study, we develop a method of measuring WFP after the adhesion strength measurement of MUF resins under shear stress. The fractured wood surface of b lock shear strength (BSS) specimens bonded with cold-setting MUF resins at three melamine contents (20%, 30%, and 40%) was marked black, and then, WFP was accurately measured via image analysis. WFP values measured using this method consistently increased with BSS as the melamine content increased, showing the reliability of this new method. The results suggested that this new method is useful and reliable for measuring the WFP of the fracture surface of wood specimens bonded with colorless adhesives such as urea-formaldehyde, MUF, and melamine-formaldehyde resins.

Evaluation of mechanical properties and non-flammability of Nylon6 using melamine-based halogen-free flame retardant (Melamine계 난연제를 이용한 Nylon6의 난연성 및 물리적 특성 평가)

  • Kim Dong-Hak;Ryu Kwan-Suk;Son Young-Gon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.7 no.4
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    • pp.743-748
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    • 2006
  • We investigated the flame retardancy and the mechanical properties of Nylon6 by using melamine-based halogen-free flame retardants(melamine cyanurate:MC-100 and melamine phosphate:MP-100). We chose the UL-94 method for flame retardancy and measured the tensile strength, flexural strength, flexural modulus by using UTM and impact strength by using Izod impact tester. We also tested the effect of nano-clay on flammability and mechanical properties. We obtained the V0 grade when the concentration of flame retardant was over 5 wt%. The tensile strength and flexural strength decreased and flexural modulus increased with the concentration of both flame retardant systems. The results showed that MC-100 system was better than MPP-100 system. Because of poor dispersion, we did not obtain the synergistic effect of nano-clay.

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Hard Coatings on Polycarbonate Plate by Sol-Gel Reactions of Silicates and Melamine Derivative (폴리카보네이트 판 위에 Silicates와 Melamine 유도체의 졸-겔 반응을 이용한 하드 코팅)

  • Kim, Se-Ra;Kang, Min-Kyung;Shin, Young-Jae;Oh, Mee-Hye;Yoon, Yeo-Seong;Shin, Jae-Sup
    • Polymer(Korea)
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    • v.31 no.6
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    • pp.485-490
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    • 2007
  • Hard coating was made on a polycarbonate plate using a sol-gel process with a melamine derivative and silicates, and examined as potential substitutes for automobile glass. Methylated poly(melamine-co-formaldehyde), tetraethoxysilane, and phenyltriethoxysilane were used to form a coating solution. The coatings on the polycarbonate plate were deposited using a sol-gel process. Poly(methyl methacrylate) was coated on the surface of polycarbonate in order to improve adhesion property. The optimum conditions and formulation to obtain excellent physical properties of the coating were determined. Adding the melamine derivative to the coating solution, the pencil hardness of the coating was improved. The hardness of a 3H class pencil, excellent abrasion resistance, and surface uniformity were found in the coated polycarbonate surface.

Establishment of Analytical Methods for Melamine Related Compounds in Biological Samples (생체시료 중 멜라민 화합물의 미량분석법 개발연구)

  • Han, Kyoung-Moon;Kim, Jin-Ho;Cho, Soo-Yeul;Shim, Sun-Bo;Lee, Jin-Hee;Lee, Ji-Hyun;Hwang, In-Sun;Kim, Sung-Il;Cho, Yang-Ha;Chai, Gap-Yong;Kwon, Soon-Jae;Lee, Jun-Ho
    • Journal of Food Hygiene and Safety
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    • v.26 no.2
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    • pp.125-141
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    • 2011
  • Melamine has raised international concerns for its catastrophic health effects from tainted infant formula. This report concerns the developmental validation of a sensitive HPLC/MS/MS and GC/MS methods about melamine and cyanuric acid in human urine and serum. Analytical detection ranges of LC/MS was from 0.2 to 5.0 ng/mL and 2.0 to 60.0 ng/mL about melamine and cyanuric acid, respectively. The limits of quantification and confirmation are 0.2 ng/mL for both analytes in human urine and serum by LC/MS/MS. The range of recovery was 91.6%, and 107.6% for cyanuric acid and melamine in urine, respectively. The range of precision coefficient variation was from 2.0%, to 11.8% for cyanuric acid and melamine in urine. The range of recovery was from 94.9%, to 119.0% about cyanuric acid and melamine in serum, respectively. The range of precision coefficient variation from was 3.7%, and 13.5% about cyanuric acid and melamine in serum. Analytical detection ranges of GC/MS were 5.0 to 100.0 ng/mL about melamine and cyanuric acid, respectively. The limits of quantification and confirmation are 5.0 ng/mL for both analytes in human urine and serum by GC/MS. The range of recovery was from 83.7%, to 114.5% for cyanuric acid and melamine in urine, respectively. The range of precision coefficient variation was 3.5%, and 10.7% for cyanuric acid and melamine in urine. The range of recovery was 94.4%, and 110.7% for cyanuric acid and melamine in serum, respectively. The range of precision coefficient variation from was 3.9%, and 13.8% for cyanuric acid and melamine in serum. Several changes were taken to optimize performance by this method.