• Composites Research
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• v.12 no.6
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• pp.15-21
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• 1999

Carbon fibers were coated with carboxy modified poly(hydroxy ether)(C-PHE, water dispersed), water soluble polymers poly(hydroxy ether ethanol amine)(PHEA) or water insoluble poly(hydroxy ether)(PHE). Interfacial shear strength of polymer coated carbon fibers was measured by micro-droplet tests with vinyl ester resin, and approximately 30 samples were tested. The interfacial adhesion of poly-mers to carbon fibers was also evaluated, and diffusion behavior of polymer films in vinyl ester resin was investigated. The carbon fibers after testing and diffusion samples were analysed by SEM in order to understand adhesion mechanism. Interfacial shear strength of carbon fibers was enhanced by the coating of PHE and C-PHE which have good or marginal solubility in vinyl ester resin, respectively, but not by the coating of PHEA possibly due to the poor solubility in vinyl ester resin.

• Tribology and Lubricants
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• v.30 no.6
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• pp.343-349
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• 2014

Currently, in order to resist the scratching of the fuel rod surface while fabricating the fuel assembly of the light-water nuclear reactor, we use a solution of nitrocellulose, an explosive material, as a dry lubricant along with its solvent. However, the demand for developing safe and harmless aqueous alternative materials for environment-conservation and field-worker safety has increased. In this study, we demonstrate the preparation of a novel aqueous resin composite using a formulation of aqueous polymeric resin, alcoholic solvent, and water. Subsequently, we characterize this composite on the basis of hardness, adhesive property, and water solubility using plates similar to the fuel rod material. The insertion test of a fuel rod coated with the YS-3 composite shows load values of $18.8-20.5kg/cm^2$, which is comparable with $18.8-20.5kg/cm^2$ of the nitrocellulose coating agent. In addition, the depth and width of longitudinal scratches caused by the YS-3 composite test are 50% higher than those of the standard. We can develop a harmless and safe aqueous dry lubricant to replace the existing NC products through field testing of 264 pieces of fuel rods, after producing 350 kg of the YS-3 prototype. The scratch test for the rod surface showed that weight of chip of YS-3 prototype was smaller than that of NC before and after solvent treatment, indicating the properties of YS-3 prototype was comparable to the counterpart.

• Journal of the Korea Institute of Building Construction
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• v.9 no.5
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• pp.71-77
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• 2009

In a range of forms, such as latex, water-soluble polymer, liquid resin, and monomer, polymer dispersions have been widely used in the construction industry as cement modifiers because of their excellent properties, such as acid-resistance, water-proofness, and good ductility in mortar and concrete. Polymer cement slurry (polymer-modified slurry) is made of cement and polymer dispersions, with a high polymer-cement ratio of 50% or more. The purpose of this study is to evaluate the water permeability and drying shrinkage of polymer cement mortar (polymer-modified mortar) and cement concrete coated by polymer cement slurry. The polymer cement mortar and cement concrete are prepared with various polymer types, polymer-cement ratios and curing methods, and are tested for water permeability, drying shrinkage and strength. The test results showed thatthe weight of permeable water of polymer cement mortar decreases with an increase in the polymer-cement ratio, reaching a minimum at the polymer-cement ratio of 20%. In particular, the weight of permeable water of St/BA-modified mortar with a polymer-cement ratio of 20% coated with St/BA-modified slurry is about 1/55 that of unmodified mortar. The EVA- and St/BA-modified slurries coated on cement concrete have about 4 or 5 times higher drying shrinkage compared to cement concrete. The strength of polymer cement mortars tends to increase with a higher polymer-cement ratio, and is considerably higher than that of unmodified mortar. It is thus concluded that polymer cement mortars coated by polymer cement slurry are effective for industrial application, and have superior properties such as waterproofness and strengths, compared with conventional cement mortar.

• Polymer(Korea)
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• v.36 no.5
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• pp.662-667
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• 2012

Poly(ethylene terephthalate) (PET) base films with high light transmittance have been used for the substrate of various functional films in the flat panel display. The effects of the reflective index of coated films, the roughness of the film surface and the content of inorganic silica particles on the light transmittance were studied in this article. Light transmittance was increased by coating a water soluble resin with a low reflective index at an optimum thickness. The roughness of the film did not affect light transmittance when the Ra of the film surface was less than a quarter of the wavelength of incident light. Inorganic silica particles decreased light transmittance due to their absorbance and scattering of the incident light.

• Journal of Conservation Science
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• v.26 no.3
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• pp.335-340
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• 2010

Urethane resin applicable for the first transcription of historical site and transcription of soil layer were synthesized in order to replace the imported urethane resin, NS-10. Comparing to the NS-10, the urethane polymers showed similar penetration to wet soil and formed a stable layer of polyurethane during progress working the peeling off the polyurethane pre-product from epoxy surface of final product. The urethane resins used for the first transcription of historical site improved tensile strength, which is consistent with that of NS-10. In addition the urethane resin for transcription of soil layer was supplied with hardness that have a also same strong point as like NS-10. This property is advantage due to simplifying the transcription work of soil layer in backward. When we tested to the real ground soil as well as experimentation compressed soil with use these synthesis urethane resin, we ca get the satisfying result in penetration property and stability and these properties evaluated the resins as an advanced product serving better convenience for worker.

• Analytical Science and Technology
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• v.14 no.1
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• pp.72-79
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• 2001

Oxidative decomposition of 2, 4, 6-trichlorophenol(TCP) was studied in aqueous solution. Iron and manganese protoporphyrin [or tetrakis(p-carboxyphenylporphyrin)] and their polymer supported derivatives were used as catalysts, and $KHSO_5$ and tert-butyldroperoxide(TBHP) as oxidants. Metalloporphyrin itself shows very poor catalytic activity in oxidative decomposition of TCP with oxidant. However, very high catalytic activity was observed when metalloporphyrin was chemically bound to newly synthesized polymers or XAD2 resin. Additionally, it revealed much higher catalytic activity in the presence of water-soluble polymers having a electron-donating axial ligand such as pyridine and immidazole. Maleic acid and chloromaleic acid were found in the resulting solution by ESI-MS. Especially, XAD2-supported metalloporphyrins can be reused as catalysts due to insolubility to solvent, and stability against oxidant.

• Korean Journal of Food Science and Technology
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• v.43 no.2
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• pp.149-155
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• 2011

This study was carried out to develop a method of removing unnecessary sugars and high-molecular weight soluble components from water extract by using various highly porous polymer resins: these resins are widely used as adsorbents for polyphenolic compounds. Each anthocyanin-rich fraction (ARF) that was eluted from column packed with 4 different resins (SEPABEADS SP207, 700, 850 and Diaion HP 20) was obtained from an aqueous extract of the ripe fruits of Rubus coreanus, which is well-known in Korea as "Bok-bun-ja". Among the above mentioned resins, Diaion HP20 had the highest efficacy and provided maximum yield of the ARF. The ARF eluted from the column packed with HP 20 exhibited the strongest antioxidant activity in vitro. Bioactive phytochemicals extracted from Rubus coreanus were investigated using the on-line HPLC-$ABTS^{{\cdot}+}$ system, and the resulting 6 peaks were identified as radical-scavenging components. By using liquid chromatography-mass spectrometry, 5 peaks were obtained, and these were identified as cyanidin-3-sambubioside, cyanidin-3-glucoside, cyanidin-3-xylosylrutinoside, cyanidin-3-rutinoside and pelargonidin-3-rutinoside. These results indicate that the use of appropriate porous resin (Diaion HP 20) leads to an increase in the yield of bioactive components and enhancement of their biological properties.