• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.2
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• pp.158-164
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• 1994

These experiment were conducted to evaluate the environmentally acceptable polymers, and 10 polymers were used in these study, and to investigate conductivity, germination percentage, water uptake of polymeric coating soybean seed. The conductivity of polymeric coating seed is higher than that of none coating seed and the highest conductivity was obtained with waterlock coating seed among the 10 polymer coating seed. As the soaking time was long, the conductivity was increased. The conductivity of large seed was higher than that of small seed, and that of long period storage seed was higher than that of short period storage seed. The effects of seed coating polymers on uptake water were various, and daran 8600 inhibited uptake water of low quality seed. The waterlock, captan, klucel and sacrust was rised germination percentage, and daran 8600 was declined germination percentage, and the effect of coating polymers on germination percentage of low quality seed was higher than that of high quality seed.

• KCI Concrete Journal
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• v.13 no.2
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• pp.42-48
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• 2001

The bend resistance of coated reinforcing bar is greatly influenced by both the adhesion strength between bar and coating materials, and the followed transformation of coating material as bars bend. Especially, tearing state or partial microscopic cracks are predicted on the inside and outside of bending angle, because tensile strength and elongation of polymer film are very different according to types of polymer dispersions in bar coating, and these damaged parts are rapidly corroded by penetration of corrosive factors. In this study, polymer cement slurry coated reinforcing bars with various polymer dispersions are prepared by following combined conditions, polymer-cement ratio of 50% and 100%, coating thickness of 250$\mu$m and 450$\mu$m, coating number, curing age of 3, 7, 14 and 28days. Then the specimens are tested for working life and bend resistance at bending angles $90^{\circ}$, $135^{\circ}$and $180^{\circ}$ to observe the microscopic damage effect as the bars bend. Also, epoxy-coated reinforcing bars for control experiment were used with 250$\mu$m of coating thickness. The tensile strength for polymer films is performed. From the test results, the working life of the polymer cement slurry is within 90 seconds. Among four types of polymer dispersion, polymer cement slurry coated reinforcing bar using St/BA-1 emulsion has the excellent bend resistance, which is remarkably improved than that of epoxy-coated reinforcing bar. And the bend resistance is more related to elongation than tensile strength of polymer film. Polymer cement slurry with a polymer-cement ratio of 100%, a coating thickness of $450\mu$m and one coating using St/BA emulsion is selected as a most suitable coating material for coated reinforcing bar.

• Polymer(Korea)
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• v.38 no.3
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• pp.391-396
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• 2014

Polymer microneedles can be fabricated by a micromolding method, an easy and cost-effective method. However, it is not easy to achieve uniform coating with an aqueous coating solution due to hydrophobic surface of polymer microneedles. 3-Dimensional coating polymer microneedles could deliver more than twice as much dose as in-plane metal microneedles by increasing coating area and the number of microneedles per unit area. A uniform coating was not obtained by addition of coating additives in the coating solution. The satisfied coating was achieved by treatment of surface of polymer microneedle with metal deposition and UV/ozone, and UV/ozone treatment was an ultimate surface treatment method based on biological safety. Calcein coating polymer microneedles were prepared by using UV/ozone treatment and followed dip-coating, and they delivered calcein in porcine skin successfully after 15 min of insertion.

• Journal of Pharmaceutical Investigation
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• v.37 no.1
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• pp.7-13
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• 2007

To produce stable polymer coating layer using the interaction between metal stent and polymer layer, Ahx-HSAB was synthesized by coupling 6-aminoheanoic acid (Ahx) with N-Hydroxy succinimidyl 4-azidobenzonate (HSAB) containing photo reactive group. Then, Ahx-HSAB was applied to self·assembled monolayer (SAM) on $TiO_2$-coated surface, since one end of Ahx-HSAB was carboxyl acid which was known to be able to interact with $TiO_2$ surface. That SAM layer was incubated in 1% polycaprolacton (PCL) solution and photoreacted by ultraviolet light (254 nm) to produce the chemical bond between SAM and polymer layer, followed by PCL polymer coating ({\sim}5\;{\mu}m$) by the method of spray coating. The surface change was investigated by measuring of contact angle of the surface. The contact angle values of stainless steel (SS) surface, $TiO_2$-coated surface, SAM layer by Ahx-HSAB, photoreacted surface with PCL and PCL layer by spray coating were 70.48${\pm}$1.89, 38.57${\pm}$3.31, 60.14${\pm}$2.21, 54.91${\pm}$2.70 and 56.47${\pm}$2.12, respectively. The stability of polymer layers was tested by incubation of PCL-coated plates in 0.1M PBS buffer (pH 7.4, 0.05%, Tween 80) with vigorous shaking (200 rpm). While the poiymer layer prepared by these processes showed the intact surface morphology over 3 days, the polymer layers prepared by spray coating of PCL onto SS plate (control 1) and $TiO_2$-coated SS plate (control 2) were Peeled off in 3 days. Thus, the polymer coating method using SAM and photoreaction seems to be a effective method to obtain the stable polymer layer onto SS surface.

• Journal of Environmental Health Sciences
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• v.24 no.2
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• pp.104-109
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• 1998

The objective of this study was to examine the effect of polymer coating on the initial microorganism attachment and the biofilm growth. Such as nonion(polyacrylamine), anion(CMC-Na) and cation polymer coagulant(chitosan and PEI) were used for coating material of the support carrier(acryl plate). When polymer coagulant was coated with 5, 10, 20, 35, 50, 100 and 200 mg/l on the surface of acryl plate, initial microorganism attachment increased and optimum concentration for the attachment was 35 mg/l. Biofilm growth experiments were conducted with the substrate loading of 12.7gSCOD/$m^2\cdot$ day using RBC. The polymer coagulants such as CMC-Na, polyacrylamide, PEI and chitosan coating on the acryl plate facilitated the biofilm growth of microorganisms. Until the biofilm dry weight grows up to 0. 0038g/cm$^2$, biofilm growth on the plate coated with cation polymer like chitosan was better than that on the coated plate of nonion(polyacrylamine), anion(CMC-Na) polymer coagulant.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.136-136
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• 2016

Commonly used oil-based polymer resin has environmental and safety issues. Many researches for replacing the harmful solvent-borne resins to water-borne resins have been investigated to purify harmful environmental resources and follow the export and import of hazardous materials regulations. In this research, ultrasonic spray coatings of aqueous polymer resin were studied to fabricate thin insulating layer (${\sim}{\mu}m$) on the rectangular copper wire. It needs to have appropriate wettability between resin and substrate during the ultrasonic spray coating process to coat aqueous polymer uniformly. Furthermore, stabilities of coating solution and fabricating process are required to form thin insulating layer on the substrate. In here, physical characteristics such as viscosity of 6 types of commercial polymer dispersions and emersions were analyzed to confirm compatibility for ultrasonic spray coating process. These resins were dissolved in isopropyl alcohol, used for true solvent, and were diluted with ethanol, utilized for diluent. Also, solubilities, dispersion characteristics, and viscosities of these diluted polymer resin solutions were confirmed. Dispersion characteristic and viscosity of coating solution affects jetting of ultrasonic spray coating and these jetting characteristics influence morphologies of insulating layer. In conclusion, we have known that aqueous polymer solution should have outstanding dispersion characteristic and certain range of viscosity to fabricate thin polymer insulating layer uniformly with ultrasonic spray coating.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.803-806
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• 2005

The effect of coating method and binder content on the tensile adhesion strength, water absorption and cl- penetration depth of polymer-modified pastes using redispersible polymer powders and ceramic powder are examined. As a result, the tensile adhesion strength of the polymer-modified pastes tend to increase with increasing binder content and: number of coating. The water absorption and cl- penetration depth of the polymer-modified pastes tend to decrease with increasing binder content and number of coating.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.3
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• pp.274-285
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• 1996

These experiments were conducted to evaluate the effects of seed coating with ten environmentally acceptable polymers, on germination percentage, water uptake, respiration, emergence and seedling growth characteristics. The water absorption of polymer-coated seeds in saturation condition was highest in klucel and lowest in polyvinyl pyrrolidone(PVP), and that in water was highest in klucel and lowest in maltrin. Respiration rates of polymer-coated seeds in Hwayoungbyeo and Ilpumbyeo were lower than those of none-coated seeds, and those in Daecheongbyeo and Jinmibyeo were higher than that of none-coated seeds, and those of sepiret coated seeds were higher than PVP coated seeds. The germination polimer-coated seed was reduced by one percentage by coating with seed coating machine. Germination percentage was not affected by any of polymer coating in high quality seed, but there were significant effects in low quality seed coating with waterlock, surelease 46 and sepiret significantly reduced germination some cultivars. Germination percentage after accelated ageing treatment were slightly higher most of polymer-coated seeds than in none-coated seeds, but those of sepiret-and klucel-coated seeds were lower significantly. Germination percentage of seeds coated with daran 8600, rnaltrin, sacrust and opadry were enhanced slightly under cold test other polimers reduced germination. The seedling height of polymer-coated seeds were longer than those of none-coated seeds, but those of waterlock, PVP and maltrin coating seeds were shorter, seedling hight was shortened by polimer coating under cold test. Polymer-coated seeds showed higher emergence percentage, shorter emergence time in field condition. The highest emergence percentage and the shortest emergence time was shown at 90% soil moisture content.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.16 no.1
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• pp.5-7
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• 2010

Two kinds of polymer coating (acrylic polymer and vinyl acetate ethylene copolymer) added with 5% nisin were fabricated on the paperboards and tested in their antimicrobial activity against Micrococcus flavus ATCC 10240 inoculated into water contacting the coating at $10^{\circ}C$. Vinyl acetate ethylene copolymer giving faster and higher nisin migration presented the greater reduction in the microbial count than the other coating, which endorsed that the migrated nisin is mainly responsible for the microbial inhibition or destruction. There was also a slight effect of the coating polymer itself in the microbial inhibition.

• Korea-Australia Rheology Journal
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• v.20 no.2
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• pp.89-94
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• 2008

To satisfy good mechanical and optical properties of polymer-coated film products, it will be indispensable to elucidate the molecular orientation of polymer chains within coating liquids in coating flows. Using hybridized numerical method between computational fluid dynamics (CFD) and Brownian dynamics (BD) simulations can provide the useful information for the better quality control of coated films. Flexible polymer chains, e.g., ${\lambda}$-DNA molecules here, change their conformation according to the flow strength and the flow type. The molecular conformation within the coated film on the web or substrate is quite different, because the polymer chains experience the complicated flow strength and flow types in flow field. Especially in the slot coating flow, these chains are more extended by the extension-like flow field generated in the free surface curvature just beyond the downstream die region. Also, the polymer chain extension beneath the free surface can be affected by the die geometry, e.g., the coating gap, changing flow field.