• Corrosion Science and Technology
• /
• v.7 no.5
• /
• pp.269-273
• /
• 2008

It is known that the fluoric resin has the most outstanding properties in the extremely acidic environment of high temperature. However, this resin is the thermal hardening type that needs long time heat treatments above $250^{\circ}C$. It's impossible to use in situ in the extremely acidic environment such as a huge FGD ductworks or industrial chemical tanks. Furthermore, even the natural hardening type fluoric coatings which can be hardened less than $120^{\circ}C$ can not be applied to the highly acidic environmental plants because of its chemical resistance. In this study, new fluoric coatings that has excellent thermal resistance, chemical resistance and corrosion resistance has been developed in order to solve above problems and to be applied to the large plant structures in the field. These newly developed coatings are organic and inorganic composite type that have fluoric rubber(100 wt%), fluoric resin(5~50 wt%), oxalates(5~30 wt%), inorganic fillers mixed with plate-type and bulk-type solids(20~150 wt%), hardeners(0.5~5 wt%), and hardening hasteners(0.1~3 wt%). The best chemical and physical properties of these coatings are acquired by variation of adhesive reinforcement agents, dispersants, leveling agents. Mixing ratios of plate-type and bulk-type inorganic fillers influence the thermal properties, abrasive resistance and chemical infiltration properties of coatings. The mixing control is also very important to have homogeneous surface and removing inner voids of coatings.

• Progress in Superconductivity and Cryogenics
• /
• v.4 no.1
• /
• pp.13-16
• /
• 2002

$SrZrO_3 $resistive oxide barriers on Ag sheathed Bi2223 tapes were prepared by the sol-gel and dip coating method to reduce AC coupling loss. The performance of the dip-coated $SrZrO_3 $ thin films was evaluated in terms of bond strength by varying the Sr/Zr mol ratio and the amount of organic vehicle (ethyl cellulose and a-terpineol) additives. The bond strength of the coatings increased as the Sr/Zr ratio decreased and the amount of organic vehicle rose, respectively. It was found that the effect of organic vehicle addition was more pronounced, suggesting that the adherence of the $SrZrO_3 $ films on Bi2223 tapes was governed primarily by the amount of organic vehicle additive.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2006.11a
• /
• pp.313-314
• /
• 2006

In this paper, the inorganic-organic thin film encapsulation layer was newly adopted to protect the organic layer from moisture and oxygen. Using the electron beam, Sputter and Spin-Coater system, the various kinds of inorganic and organic thin-films were deposited onto the Ethylene Terephthalate(PET) and their interface properties between organic and inorganic layer were investigated Results indicates that the SiON/PI/SiON/PI/PET barrier coatings have high potential for flexible organic light-emitting diode(OLED) application.

• Polymer(Korea)
• /
• v.36 no.5
• /
• pp.622-627
• /
• 2012

This study focuses on mechanical property enhancement and volatile organic compounds (VOCs) reduction characteristic of environmentally-friendly waterborne coatings. We synthesized a series of organic-inorganic hybrid waterborne polyurethanes by using poly(tetramethylene glycol) 2000, polycarbonate diol 2000, isophorone diisocyanate, dimethylolpropionic acid and titanium dioxide. The study on the effects of the R ratio([NCO]/[OH]) and inorganic contents on environmentally-friendly waterborne coatings showed that the R ratio with more than 1.5 is appropriate due to arrangement of hardsegments. The applied $TiO_2$ on films reduced volatile organic compounds (VOCs).

• Clean Technology
• /
• v.23 no.2
• /
• pp.148-157
• /
• 2017

To prepare UV-curable polyurethane-acrylate oligomer, NCO-terminated urethane prepolymers with trimethylolpropane, [TMP; 0 (0), 0.1 (0.021) and 0.2 (0.043) mole (mole fraction)] as crosslinkable tri-functional chain extender were end-capped with pentaerythritol triacrylate [PETA; 2.0 (0.400), 1.7 (0.354) and 1.4 (0.304) mole (mole fraction)] with one hydroxyl group/three vinyl functionalities. The stable as-formulated UV-curable polyurethane-acrylates [stable mixtures of PETA-capped oligomer/reactive acrylic monomer diluents without/with heptadecafluorodecyl methacrylate (PFA; 0, 6 and 9 wt%)] were formed up to 0.2 (0.043) mole (mole fraction) of TMP content in the prepolymer, while homogeneous-mixing failed at 0.3 (0.068) mole (mole fraction), in which the crosslink density in NCO-terminated urethane prepolymer was too high to enable the formation of stable mixture. This study examined the effect of TMP/PETA molar ratio and heptadecafluorodecyl methacrylate (PFA) content (wt%) on the properties of UV-cured polyurethane-acrylates as marine antifouling coating materials. The properties of UV-cured polyurethane-acrylate were found to be significantly dependent on the crosslinkable TMP/PETA ratio and PFA content. With the increasing of the TMP and PFA contents, the contact angles increased, and consequently the surface tension decreased. The adhesion of algae/barnacles to PFA contained film samples were found to be sufficiently weak to allow their easy removal. These results suggest that the UV-cured samples containing PFA have strong potential as coating materials for antifouling applications.

• Elastomers and Composites
• /
• v.35 no.1
• /
• pp.12-18
• /
• 2000

With growing concerns of environment and due to strengthening the government regulations on volatile organic compounds(VOC) the coatings industries are developing new technologies to reduce the amount of VOC released from coatings. In this study. a water soluble curing agent of amino-epoxy adduct was synthesized and its structure was identified by FT-IR, GPC and TG/DTA. The mechanical properties of the new curing agent in combination of KER-828 and KER-500 were investigated respectively. As an experimental result, the drying time of KER-828 was faster than that of KER-500 but the adhesion and impact strength of KER-500 was better than that of KER-828.

• Journal of Environmental Science International
• /
• v.17 no.8
• /
• pp.925-932
• /
• 2008

Manufactures of automotive repair finishes are tending to reduce more and more the level of volatile organic compounds (VOCs) in their paint processes in order to comply with increasingly strict environmental legislation. The production of high solids paints is a way to solve this problem. However, the application of high-solids paints is limited primarily by the viscosity of resin which is strongly related to painting ability: the higher solid content, the lower desired property. In this study, alkyl copolymer with low viscosity was synthesized by the introduction of the monomers with long-side chains and functional groups which improve flexibility and cross-linking density, respectively. The solid content of the paint prepared with the synthesized resin was 80wt% and its VOCs was reduced by 20%, compared to the commercialized paint. Also, the physical and mechanical properties of coatings on steel sheets were similar to commercialized one.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2016.11a
• /
• pp.194.2-194.2
• /
• 2016

Magnesium has many desirable properties of which the high strength/weight ratio makes it extremely valuable in automobile and aerospace industry. However, the high corrosion susceptibility of magnesium and its alloys has greatly limited their large scale use for various applications. Organic coating is one of the most effective ways to prevent magnesium alloys from corrosion. An organic coating is normally used in the final stage of a coating process. It can enhance corrosion resistance of magnesium and its alloys. Organic coating involves a variety of process such as painting, powder coating, cathodic electrocoating (E-painting) and the application of lacquers, enamel and varnishes.

• Proceedings of the Polymer Society of Korea Conference
• /
• 2006.10a
• /
• pp.315-315
• /
• 2006

A variable surface coating with the potential to fulfill the requirements of industry will be presented. Via controlled radical polymerization methods from a functionalized Polymethylsilsesquioxane delivers an inorganic-organic block copolymer, which can be easily modified and tuned for different applications. Spin coated or dip coated on various substrates show promising results. By using different block copolymers the contact angle on a silicon wafer can be varied in a range of $90^{\circ}\;up\;to\;145^{\circ}$ After curing and complete condensation a perfect adhesion on glasses, plastics and metals is achieved.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2012.05a
• /
• pp.124-125
• /
• 2012

Korea institute of materials science (KIMS) use a linear deposition source called as a closed drift linear plasma source (CDLPS) as well as dual magnetron sputtering (DMS) to deposit SiOxCyHz films in $HMDSO/O_2$ plasma. The CDLPS generates linear plasma using closed drifting electrons and can reduce device degradations due to energetic ion bombardments on organic devices such as organic photovoltaic and organic light emission diode by controlling an ion energy. The deposited films are investigated by Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). Optical emission spectroscopy (OES) is used to measure relative radical populations of dissociation and recombination products such as H, CH, and CO in plasma. And SiOx film is applied to a barrier film on organic photovoltaic devices.