• Journal of the Korean Society of Clothing and Textiles
• /
• v.2 no.1
• /
• pp.125-131
• /
• 1978

This study was intended to clarify (1) the release of free formaldehyde (2) transfer of free formaldehyde to the contacted fabrics during storing, and (3) the removal effect of free formaldehyde by washing from resin finished fabrics. The results of this study were as follow; 1. The decrease rate of free formaldehyde content in fabrics was higher during storing in open air, poly bag, and glass tube in descending order and the content of free formaldehyde in fabrics was decreased in glyoxal resin finished but, increased in Melamine M-3 resin finished when the fabrics was stored in polybag and in glass tube. 2. Increased amount of formaldehyde transfer to contacted fabrics was noted with Melamine M-3 resin finished than that of glyoxal resin finished. Increased amount of formaldehyde transfer as well as more free formaldehyde were noted in cotton fabrics than in polyester/ cotton blend. 3. The effect of removing free formaldehyde from the fabrics was better in case of solid alkaline soap, synthetic alkaline powdered detergents, neutral detergents in descending order. The romoval of free formaldehyde was marked after the 1st washing and almost no increase in free formaldehyde was found after three times of washing. 4. After first washing, the content of formaldehyde in Melamine M-3 resin finished fabrics increased more rapidly than that of glyoxal resin finished fabrics in condition of closed storing.

• Polymer(Korea)
• /
• v.34 no.5
• /
• pp.480-484
• /
• 2010

A series of poly(amic acid)s(PAAs) was prepared by reacting 4,4'-(4,4'-isopropylidenediphenoxy) bis(phthalic anhydride)(BPADA) as the anhydride monomer and 2,2'-bis(trifluoromethyl) benzidine (TFB), bis(3-aminophenyl)sulfone (APS), 4,4'-methylenebis-(2-methylcyclohexylamine) (MMCA), or bis[4-(3-aminophenoxy) phenyl] sulfone (BAPS) as the amine monomer with 5 mol% melamine in N,N-dimethylacetamide (DMAc). Colorless and transparent polyimide (PI) films were obtained by casting the PAAs at various heat treatment temperatures. The thermo-mechanical properties and optical transparency of the PI films were investigated. The thermal properties of the PI films were examined using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and thermomechanical analysis (TMA), and their optical transparency were measured by spectrophotometry. The coefficient of thermal expansion (CTE) and yellow index (YI) values of all samples were in the range of $48.53-64.24ppm/^{\circ}C$ and < 3.0, respectively.

• Journal of the Korean Wood Science and Technology
• /
• v.43 no.6
• /
• pp.792-797
• /
• 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
• /
• v.33 no.2 s.130
• /
• pp.29-39
• /
• 2005

Formaldehyde emissions from wood-based panels bonded with pine and wattle tannin-based adhesives, urea-formaldehyde resin (UF), melamine-formaldehyde resin (MF), and co-polycondensed resin of urea-melamine-formaldehyde (UMF) were measured by the Japanese standard method using a desiccator (JIS A 1460) and the EN 120 (European Committee For Standardization, 1991) method using the perforator value. In formaldehyde emission, all particleboards made using the wattle tannin-based adhesive with three different hardeners, paraformaldehyde, hexamethylenetetramine, and tris(hydroxyl)nitromethan (TN), satisfied the requirements of grade $E_1$. But only those made using the pine tannin-based adhesive with the hexamine as hardener met the grade $E_1$ requirements. Hexamine was effective in reducing formaldehyde emission in tannin-based adhesives when used as the hardener. While the UF resin showed a desiccator value of $7.1mg/{\ell}$ and a perforator value of 12.1 mg/100 g, the MF resin exhibited a desiccator value of $0.6mg/{\ell}$ and a perforator value of 2.9 mg/100 g. According to the Japanese Industrial Standard and the European Standard, the formaldehyde emission level of the MDF panels made with UF resin in this study came under grade $E_2$. The formaldehyde emission level was dramatically reduced by the addition of MF resin. The desiccator and perforator methods produced proportionally equivalent results. Gas chromatography, a more sensitive and advanced method, was also used. The samples for gas chromatography were gathered during the experiment involving the perforator method. The formaldehyde contents measured by gas chromatography were directly proportional to the perforator values.

• Journal of the Korea Concrete Institute
• /
• v.17 no.6 s.90
• /
• pp.1019-1024
• /
• 2005

To research effects of various chemical superplasticizers(Lignosulfonic acid, Naphthalene sulfonated formaldehyde condensate, melamine sulfonated formaldehyde condensate, and Polycarboxylate) on the hydration of cement, experiments involving XRD, SEM, and DSC have been analysed with cement paste specimens. Regardless of types and dosages of superplasticizers, hydration reaction of specimen applied superplasticizer was delayed to 3 day, but then it showed similarity to plain which don't add superplasticizer. Moreover, the hydrating rate of cement paste was retarded as dosage of superplasticizer was increased. Also, kinetics related with hydrate of cement paste was slow in order of lignosulfonic acid, polycarboxylate, melamine and naphthalene sulfonated formaldehyde condensate. Nevertheless, when all kinds of chemical admixtures were used, morphologies of these hydrates were denser and more uniform than those of plain.

• Journal of Adhesion and Interface
• /
• v.12 no.4
• /
• pp.105-110
• /
• 2011

Polyester/melamine cured coatings had been used for pre-primed coatings and pre-coated metal coatings, because it has good mechanical,chemical properties, and mar resistance. But it has weak points such as stiffness and low formability for making automotive components. Polyester had been synthesized using polycarbonate diol of long alkyl chain which can improve flexibility and formability which is one of the important factors for pre-coated steel sheets (PCM). In this study, strain and tensile strength were examined by the tensile test and formability was examined by the drawing test. Also, Those polyester resins were also measured by DMA to verify flexibility of cured coatings.

• Journal of the Korea Concrete Institute
• /
• v.17 no.5 s.89
• /
• pp.811-818
• /
• 2005

It is well known that the fluidity and the fluidity loss of fresh concrete are affected by the kind of organic admixtures. Organic admixture can improve the properties of concrete. Sulfonated Naphthalene-Formaldehyde(SNF) Superplasticizer is used representatively, but has a problem in fluidity loss. In this study, we synthesized the Sulfonated Melamine-Formaldehyde(SMF) superplasticizer at the various synthetic conditions and compared the physical properties with SMF superplasticizer. SW superplasticizer is synthesized with four synthetic steps. Step 1 is hydroxymethylation, Step. 2 is Sulfonation, Step. 3 is Polymerization and Step. 4 is Stabilization. Synthesis of SMF superplasticizer depends on pH, temperature and reaction time. In this reaction, we changed the mole ratio of melamine to formaldehyde at 1:3, 1:4, and the amount of acid catalyst at Step. 3. After application of SMF superplasticizer and its mixture with SNF superplasticizer to cement pastes and mortars, we measured the physical properties of them at the different dosages(0.5, 1.0, 1.5 wt%) to cement. All samples including superplasticizer showed higher compressive strengths and slump, smaller pore size and porosity than CEM

• Journal of Food Hygiene and Safety
• /
• v.29 no.1
• /
• pp.21-25
• /
• 2014

Formaldehyde and phenol used in the production of melamine-wares may be intended to come into foodstuffs. So this study investigated the migration of formaldehyde and phenol from 222 articles Articles were cups(14), bowls(75), plates(85), spoons(10), chopsticks(4), food trays(8), rice paddles(4), spatulas(9) and scoops(12). The food stimulants were 4% acetic acid, 20% ethanol, distilled water and n-heptane. Korea regulation (Standards and specifications for food utensils, containers and package) specifies migration limits for formaldehyde and phenol in food stimulants. Formaldehyde and phenol are restricted by 4 mg/L, 5 mg/L respectively. In all cases the migration of formaldehyde and phenol were below the limit set in Korea regulation. The level of formaldehyde and phenol migrated to food simulants were in the range of N.D~2.949 mg/L, N.D~0.078 mg/L respectively. These migration results of formaldehyde and phenol will provide a scientific basis for the safety management of melamine-wares.

• Proceedings of the Korean Fiber Society Conference
• /
• 2007.11a
• /
• pp.215-216
• /
• 2007

• Journal of the Korean Society of Clothing and Textiles
• /
• v.11 no.1
• /
• pp.51-62
• /
• 1987

In this study, electrostatic behavior of polyester and nylon fabric treated with anti-static agents were investigated. The effects of the concentration of the agents and curing conditions on the electrostatic charge of the fabrics were studied. And washfastness, lightfastness and physicalproperties of the treated fabrics were also investigated. The results were as follows: 1) Polyethylene glycol alkylester was more effective in antistatic behavior than polyethylene laurylphosphate, and polyester is more effective in anti-static behavior than nylon. 2) Concentration of anti-static agents were suitable in concentration of $4\%$. 3) Glyoxal resin was more effective in anti-static behavior than melamine resin, and it was also good in the retaing anti-static behavior after treatments of lightfastness and washfastness. 4) As the condition of curing treatment, $190^{\circ}C$, 1min. for glyoxal resin and $130^{\circ}C$, 4min. for melamine resin is appropriate. 5) In comparison of anti-static behavior according to treating conditions, the simultaneous treatment was more effective than any other treatments. 6) Change of electrostatic charge of anti-static nylon cloths after treatments of lightfastness and washfastness increased greatly in above 10 laundering time and 20 fade-O-meter time. 7) In physical properties according to concentration of treating agents. decrease of physical properties scarcely appeared in concentration of treating agents $4\~5\%$.