• Journal of the Korean Society of Safety
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• v.19 no.1
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• pp.81-87
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• 2004

Composite particles using inorganic and organic chemicals were synthesized and the results of those reaction were compared to variation of temperature and agitation speed in presence of $CaCO_3$ which was adsorbed SDBS. Also the synthesises were optimized according to conversion rate of composite particles. In inorganic/organic core-shell composite particle polymerization, $CaCO_3$ adsorbed by 0.5wt% surfactant SDBS was prepared initially and then core $CaCO_3$ was encapsulated by sequential emulsion polymerization using MMA at the addition of APS 3.16${\times}$$10^{-3}$mol/L to minimize the coagulated PMMA particle itself during MMA shell polymerization. Encapsulated PMMA on $CaCO_3$ as inorganic/organic core-shell particles was verified by FT-IR and DSC analysis. It was found that the $CaCO_3$ was very well encapsulated by PMMA as shell. The surfaces were distinctly found as spindle shape and broad particle distribution after capsulation.

• Composites Research
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• v.32 no.6
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• pp.368-374
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• 2019

Basalt fiber reinforced epoxy composites with inorganic filler (BFRP-F) such as Mg(OH)₂ (magnesium hydroxide), Al(OH)₃ (aluminum hydroxide), Al₂O₃ (aluminum oxide) and AlOOH (boehmite) were prepared by hand lay-up and hot pressing. The combustive properties of BFRP-F were improved comparing with basalt fiber reinforced epoxy composite (BFRP) without inorganic filler. At a 30 wt% resin content, the limited oxygen index (LOI) of BFRP is 28.9, which is higher than that of epoxy (21.4), and the LOI of BFRP-F is higher than that of BFRP. The BFRP-F showed the lower peak heat release rate (PHRR), total heat release (THR) and total smoke release rate (TSR) than those of BFRP. We confirmed that the flame retardant properties of the composite were improved by the addition of inorganic filler through the dehydration reaction and oxide film formation.

• Transactions of the Korean hydrogen and new energy society
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• v.33 no.1
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• pp.19-27
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• 2022

A series of QPAE/TiO₂-x (x = 1, 4, 7 and 10 wt%) organic/inorganic composite membranes were prepared as electrolyte membranes for alkaline anion exchange membrane fuel cells by controlling the content of inorganic filler with quaternized poly(arylene ether) (QPAE) random copolymer. Among the prepared QPAE/TiO₂-x organic/inorganic composite membranes, the highest ionic conductivity was 26.6 mS cm^-1 at 30℃ in QPAE/TiO₂-7 composite membrane, which was improvement over the ionic conductivity value of 6.4 mS cm^-1 (at 30℃) of the pristine QPAE membrane. Furthermore, the water uptake, swelling ratio, ionic exchange capacity, and thermal property of QPAE/TiO₂-x composite membranes were improved compared to the pristine QPAE membrane. The results of these studies suggest that the fabricated QPAE/TiO₂-x composite membranes have good prospects for alkaline anion exchange membrane fuel cell applications.

• Corrosion Science and Technology
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• v.17 no.2
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• pp.74-80
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• 2018

The electronic industries require environmentally-friendly and highly functional materials to enhance the quality of human life. Home appliances require insect repellent steels that work to protect household microwave ovens from incurring damage by insects such as fire ants and cockroaches in tropical regions. Thus, POSCO has developed new types of functional steels, coated with an array of organic-inorganic hybrid composites on the steel surface, to cover panels in microwave ovens and refrigerators. The composite solution uses a fine dispersion of hybrid solution with polymeric resin, inorganic and a pyrethroid additive in aqueous media. The hybrid composite solution coats the steel surface, by using a roll coater and is cured using an induction curing furnace on both the continuous galvanizing line and the electro-galvanizing line. The new steels were evaluated for quality performances, salt spray test for corrosion resistance and biological performance for both insect repellent and antimicrobial activity. The new steels with organic-inorganic composite coating exhibit extraordinarily biological functionalities, for both insect repellent and antimicrobial activities for short and long term tests. The composite-coating solution and experimental results are discussed and suggest that the molecular level dispersion of insecticide on the coating layer is key to biological functional performances.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.99-100
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• 2012

This study tried to present the appropriate replacement ratio of the recycled sand through the properties of the ternary system inorganic composite mortar according to replacement ratio change of the recycled sand about the natural sand through test verification. The flowing and compressive strength was degraded as the replacement ratio of the experimental result recycled sand increased. The appropriate replacement ratio of the recycled sand according to it was shown up less than 15%.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.9
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• pp.832-837
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• 2006

Antennas were fabricated by physical(adhesive) and chemical(deposition+plating) method on organic-inorganic composite material. And antennas were measured dielectric constant and gain. Dielectric constant of antennas were fabricated by physical method was decreased with increase of adhesive tape thickness and number of conduction material composition. But antennas were fabricated by chemical method was reached to 90 % of dielectric material. Gain of antennas were fabricated by physical method was decreased with increase of adhesive tape thickness. But they were unrelated with conduction material composition. The other side antennas were fabricated by chemical method excelled more 0.8 dBic than antennas were fabricated by physical method in gain of antenna. Finally, chemical method can expect excellent product process because it can produce smaller size, higher gain and elimination of many handworks.

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2367-2374
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• 2013

Lysine (Lys) immobilized on zeolite 4A was prepared by a simple adsorption method. The physical and chemical properties of Lys/zeolite 4A were investigated by X-ray diffraction (XRD), FT-IR, Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV-vis. The obtained organic-inorganic composite was effectively employed as a heterogeneous basic catalyst for synthesis of ${\alpha},{\beta}$-unsaturated carbonyl compounds. No by-product formation, high yields, short reaction times, mild reaction conditions, operational simplicity with reusability of the catalyst are the salient features of the present catalyst.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.11
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• pp.1463-1470
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• 2018

In this study, 20 types of samples were prepared by mixing different kinds of inorganic materials to develop insulation materials for epoxy - based GIS substation equipment used under high voltage environmentally friendly insulation gas. One of the electrical characteristics, AC insulation breakdown experiment was performed. As mixing ratio of mixed heterogeneous inorganic materials, the dielectric breakdown strength was increased with increasing filler ratio of micro silica, micro silica : micro Alumina, 1:9, 3:7, 5:5, 7:3, 9:1, and decreased as the filling amount of micro alumina increased. The AC insulation breakdown characteristics were the best when the composition ratio was 9:1. The higher the content of silica, the better the interfacial properties, and the larger the alumina content ratio, the worse the interfacial properties.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.350-354
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• 2009

In this work, polymer - inorganic composites have prepared using polymer such as polyethylene glycol (PEG)/poly (methyl methacrylate, PMMA) and inorganic nanofillers materials such as TiO2 nanotubes (TiNTs)/carbon nanotubes (CNTs). The extensive structural, morphological and ionic properties revealed that the high surface area and tubular feature of nanofillers improved the interaction and cross-linking to polymer matrix which is significantly enhanced the ionic conductivity and electrical properties of composite electrolytes. Comparably high conversion efficiency ~4.5% has been observed by using the newly prepared PEG-TiNTs composite solid electrolyte as compared with PMMA-CNTs electrolyte based DSSCs (~3%). The detailed comparative properties would be discussed in term of their structural, morphology, ionic and photovoltaic properties.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.6
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• pp.50-58
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• 2020

When the concrete surface layer is damaged, The method of impregnating the concrete surface with a water repellent cannot secure the expected durability. Recently, various waterproofing and water-repellent materials were mixed into concrete or mortar to secure water repellency even inside cracks, but compressive strength was greatly reduced. In order to overcome the decrease in compressive strength, there has not yet been a study using the merits of organic and inorganic materials at the same time, so in this study, the physical properties and water repellency performance were evaluated by mixing an organic/inorganic composite water repellent appropriately mixed with an organic and inorganic material into the mortar. When mixed with organic/inorganic water repellent, the flow and air content were reduced by about 10% and 50% compared to the Liquid specimen. In the case of the P6L1 specimen, it was confirmed that the compressive strength decreased by about 3.5% compared to the non-mixed mortar at 39.5 MPa, the same as the existing water repellent, Powder. Water-repellent performance The organic-inorganic composite water repellent mixture specimen confirmed higher water repellency than the existing water repellent mixture powder, and the chloride penetration resistance evaluation result showed that the organic-inorganic composite water repellent mixture specimen reduced the passing charge by about 45% compared to the non-mixed mortar. In summary, it is judged that the P5L1 organic/inorganic composite water repellent mixed with a powder water repellent and a liquid water repellent in a ratio of 5:1 is the most reasonable to prevent the decrease in compressive strength and secure water repellency.