• International Journal of Concrete Structures and Materials
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• v.8 no.3
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• pp.201-212
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• 2014

Sixteen reinforced concrete laboratory specimens were used to evaluate a number of corrosion prevention methods under an accelerated (6 months) testing program. The use of galvanic thermal sprayed zinc, galvanic embedded anodes, a tri-silane sealer, an acrylic coating, and an epoxy/polyurethane coating was evaluated. The specimens received various treatments prior to exposure to accelerated corrosion. The performance of the treatments was evaluated with respect to corrosion currents, chloride ingress, extent of cracking, severity of rust staining, and visual inspection of the reinforcing steel after the conclusion of testing and dissection. Results indicated that the tri-silane sealer, the conjoint use of galvanic thermal sprayed zinc and epoxy/polyurethane coating, the epoxy/polyurethane coating, and acrylic coating performed better than the other methods tested. Higher chloride concentrations were measured in the vicinity of embedded zinc anodes.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.232-233
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• 2006

In recent years the interest in organic/inorganic hybrid materials has increased at a fast rate. Nano organic-inorganic hybrid composites have shown advantages for preparing hard coating layers. Especially, nano hybrid composite has low environmental pollution. It has high transparency, hardness, toughness, thermal dissociation temperature, hydrophobicity by using nano sized inorganic material. There are many ways in which these materials may be synthesized, a typical one being the use of silica and silanes using the sol-gel process. The structure of sol-gel silica evolves as a result of these successive hydrolysis and condensation reactions and the subsequent drying and curing. The sol-gel reactions are catalyzed by acids and produce silica sol solutions. The silica sol grows until they reach a size where a gel transition occurs and a solid-like gel is formed. Colloidal silica(CS)/silane sol solutions were synthesized in variation with parameters such as different acidity and reaction time. In order to understand their physical and chemical properties, sol-gel coating films were fabricated on glass. From all sol-gel solutions, seasoning effect of sol-gel coating layer on glass was observed.

• Journal of the Korean institute of surface engineering
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• v.55 no.6
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• pp.425-432
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• 2022

Antifouling paints that inhibit the attachment and contamination of marine organisms mainly use TBT compounds, but because of their toxic components, they cause ecosystem disturbance and environmental destruction problems, so It is necessary to research eco-friendly antifouling paints that are easy to maintain and effective antifouling technologies. In this study, physical surface treatment of silane coating and chemical antifouling technology were applied to the metal surface to secure the stability of the surface of the marine structure and inhibit the attachment and growth of marine organisms. Adhesion of marine organisms was evaluated according to the coating conditions through surface evaluation of the charged material for 15 months in the waters of the west coast of Korea. In accordance with ASTM D6990-05, antifouling properties fouling rates (FR) and physical degradation rates(PDR) were evaluated through visual inspection of the evaluation specimens. As a result of evaluating the antifouling performance of the coated surface, it was confirmed that the antifouling performance was maintained at the 50% level even after 15 months in the sample subjected to physical processing and silane coating.

• Korean Chemical Engineering Research
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• v.54 no.2
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• pp.163-170
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• 2016

In order to improve the hydrophilic property of polymer films, coating solutions which showed a good hydrophilic property, were prepared by the sol-gel method. The coating solutions were prepared by adding different types of silane coupling agents (aminosilane, epoxysilane and acrylsilane) to a colloidal silica (15 nm diameter). The solutions prepared by adding aminosilane resulted in gels which could not be used as coating solutions. On the other hand, the coating solutions prepared by the addition of epoxysilane showed contact angles of $10{\sim}15^{\circ}$ and good hydrophilic property at R=0.10~0.15 (R=silane coupling agent/colloidal silica weight ratio). In addition, the coating solutions prepared by the addition of acrylsilane at R=0.03~0.07, exhibited contact angles of $5{\sim}10^{\circ}$, which means better hydrophilic property than aminosilane or epoxysilane.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.196-196
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• 2010

In this work, we deposited SWNTs/silane hybrid thin films by multiple spray-coating on glass substrate, and examined their electrical response for humidity. Generally silane binders which are often used in CNT solution to adhere CNTs to substrate well can be easily functionalized to each own group on the surface of CNTs after they are hardened by way of the hydrolysis reaction. We investigated how silane binders (TEOS,, MTMS and VTMS) in SWNTs hybrid thin films make effect to their electrical response on humidity. As the result, we observed that the resistance in the sample using TEOS was changed dramatically while it was almost invariant in the samples using MTMS and VTMS for increasing humidity.

• Korean Journal of Materials Research
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• v.29 no.7
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• pp.425-431
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• 2019

Generally, ceramic tiles for building construction are manufactured by dry forming process using granular powders prepared by spray drying process after mixing and grinding of mineral raw materials. In recent years, as the demand for large ceramic tiles with natural texture has increased, the development of granule powders with high packing ratio and excellent flowability has become more important. In this study, ceramic tile granule powders are coated with hydrophobically treated silica nanoparticles. The effects of hydrophobic silica coating on the flowability of granule powders and the strength of the green body are investigated in detail. Silica nanoparticles are hydrophobically treated with GPTMS(3-glycidoxypropyl trimethoxy silane), which is an epoxy-based silane coupling agent. As the coating concentration increases, the angle of repose and the compressibility decrease. The tap density and flowability index increase after silica coating treatment. These results indicate that hydrophobic treatment can improve the flowability of the granular powder, and prevent cracking of green body at high pressure molding.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.9
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• pp.967-972
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• 2004

Hardness and surface property of coated gel materials are considerably different according to kinds(particle size/stabilized ion) of colloidal silica(CS), kinds of silanes, content ratio of silane versus CS, and reaction degree in sol solution. We report the properties of sol-gel coating materials in which the factors of reaction are kinds of CS, contents ratio of CS and MTMS, and reaction time of sol. The contact angles of the coated films obtained from the mixed CS system showed a little good relationship with MTMS content increase to those from HSA CS reaction system and the change of contact angle didn't have much effect on reaction time of sol. In the coating films obtained from HSA CS reaction system, the surface was much rough in case of that the content MTMS decreased and the reaction of sol kept long. The surface roughness of films obtained from the mixed CS reaction system showed similar tendency, though its degree was a little different. In synthesis of sol-gel coating materials, we could identify that choice of CS kinds and content ratio of CS and silane were important and it was desirable the reaction time of sol is not long.

• Corrosion Science and Technology
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• v.12 no.6
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• pp.295-303
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• 2013

Silane surface treatments have been developed as an alternative for toxic and carcinogenic chromate-based treatments for years. It is consistently observed that ultra-thin films offer excellent corrosion protection as well as paint adhesion to metals. The silane performance is comparable to, or in some cases better than, that of chromate layers. Based on the tetra-ethylorthosilicate(TEOS) and methlyl trieethoxysilane(MTES), inorganic sol was synthesized and formed hybrid networks with $SiO_2$ nano particle and polypropylene glycol(PPG) on Zn alloyed steel surface. According to SST results, addition of 10nm and 50nm $SiO_2$ nanoparticle in synthesized solution improved anti-corrosion property by its shear stress relaxation effect during curing process. Also, SST results were shown that anti-corrosive property was affected by the amounts of organic compounds.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.30 no.6
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• pp.237-243
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• 2020

In this study, a silane-based coating was applied to improve corrosion resistance and thermal efficiency performance of a brazed plate heat exchanger (BPHE) composed of stainless plate and copper (Cu) brazing. Although the selected coating material was applied to the BPHE by evaluating the corrosion and contact angle according to the coating material, the result of the heat transfer performance evaluation showed that the thermal efficiency was lower than that of the uncoated BPHE. It was analyzed that the adhesion of the coating agent to the flow path inside the BPHE and the residual coating agent on the surface acted as heat resistance, preventing heat transfer. This is due to the structural characteristics of the BPHE in which a fine flow path exists inside, and it is believed that manufacturing after coating the surface of the flow path in advance in the manufacturing process of the BPHE can improve heat transfer performance.

• Polymer(Korea)
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• v.29 no.3
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• pp.242-247
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• 2005

Two kinds of colloidal silica(CS)/silane sol solutions were prepared in variation with synthesizing parameters such as kinds of CS, ratio of CS to silane and reaction time. Such sol solutions were obtained from 1034A Cs/methyl-trimethoxysilane(MTMS) and HSA CS/MTMS solutions. In the case of 1034A CS/MTMS CS/silane sol, coating film had high contact angle and more enhanced flat surface than those in the case of HSA CS/MTMS sol. In the case of thermal stability, thermal dissociation of 1034A CS/MTMS sol did not occur up to $550^{circ}$. The thickness of coating film obtained from 1034A CS/MTMS sol increased with increasing the amount of MTMS. The hardness of coating films obtained from 1034A CS/MTMS sol decreased with increasing the amount of MTMS. Surface free energy of CS/silane sol-gel coating film decreased with increasing amount of MTMS.