• Korean Chemical Engineering Research
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• v.49 no.3
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• pp.271-276
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• 2011

We investigated the possibility of introducing functional groups without damaging surface polymeric chains through the treatment of a polypropylene(PP) film immersed in liquid phase using an atmospheric pressure plasma with large area. The ionic liquid of 1-butyl-3-methylimidazolium tetrafluoroborate: $[BMIM]^{+}[BF_{4}]^{-}$- was successfully applied for generating stable plasmas in the plasma-solution system. We successfully treated the film surface using the plasma-solution system and confirmed various oxygen-containing functional groups formed on the surface of PP film. The surface free energy of PP film was increased with increasing plasma treatment time and power. It also showed a maximum value at the PP sample treated in the ionic liquid solution of 1.5 M. ATR-FTIR analyses revealed the increase of various carbonyl groups(1,726 $cm^{-1}$, 1,643 $cm^{-1}$) and OH groups$(3,100{\sim}3,500\;cm^{-1})$ after plasma treatment of PP film, and XPS also supported the ATR-FTIR result.

• Polymer(Korea)
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• v.24 no.4
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• pp.499-504
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• 2000

The effect of anodic oxidation on high strength PAN-based carbon fibers has been studied in terms of surface functionality and surface energetics of the fiber surfaces, resulting in improving the mechanical properties of composites. According to FT-IR and XPS measurements, it reveals that the oxygen functional groups on fiber surfaces induced by an anodic oxidation largely influence the surface energetics of fibers or the mechanical interfacial properties of composites, such as the interlaminar shear strength (ILSS) of composites. According to the contact angle measurements based on the wicking rate of a test liquid, it is observed that anodic oxidation does lead to an increase in surface free energy of the carbon fibers, mainly due to the increase of its specific (or polar) component. From the surface energetic point of view, it is found that good wetting plays an important role in improving the degree of adhesion at interfaces between fiber and epoxy resin matrix of the resulting composites. Also, a direct linear relationship is shown between 01s/01s ratio and ILSS or between specific component and ILSS of the composites for this system.

• Polymer(Korea)
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• v.37 no.3
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• pp.373-378
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• 2013

The interfacial adhesion strength is very important in $SiO_x$ deposited PC film for the barrier enhanced polycarbonate (PC) flexible substrate. In this study, PC films were treated by undercoating, UV/$O_3$ and low temperature plasma and then the effect of physical and chemical surface modifications on the interfacial adhesion strength between PC film and $SiO_x$ barrier layer were studied. It was found that untreated PC film shows significantly low interfacial adhesion strength due to the smooth surface and low surface free energy of PC. Low temperature plasma treatments resulted in the increase of both surface roughness and surface free energy due to etching and the appearance of polar molecules on the PC surface. However, UV/$O_3$ treatment only shows the increase of surface free energy by developed polar molecules on the surface. These surface modifications caused the enhancement of surface interfacial strength between PC film and $SiO_x$ barrier. In the case of undercoating, it was found that the increase of surface interfacial strength was achieved by adhesion between various acrylic acid on acrylate coated surface and $SiO_x$ without increase of polar surface energy. In addition, the barrier property is also improved by organic-inorganic hybrid multilayer structure.

• Applied Chemistry for Engineering
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• v.18 no.5
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• pp.467-474
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• 2007

The palladium and gold nanoparticles containing PAN-based active carbon fiber (ACF) with a high specific surface area were prepared. Using the BET, TEM, FE-SEM, and XPS, their specific surface area and pore volume, pore structure, and the change in surface oxygen groups with time were analyzed and $SO_2$ adsorption performances were investigated. Because of the impregnating process, the micropore volume was mostly decreased from 95.5% to 30.5~43.7% compared with the total pore volume. And the change in surface oxygen groups with time was higher for the metal salt than the nanoparticles. Also, $SO_2$ breakthrough time of PAN-ACFs impregnated with Au nanoparticles and metal salts did not change compared with that of the non-impregnated PAN-ACF. But the PAN-ACF impregnated with Pd nanoparticles (100 ppm) showed good $SO_2$ adsorption performance as the breakthrough time of 880 sec. These results indicated that the $SO_2$ adsorption performance depended on the change in surface oxygen groups with time and the moderate impregnation of Pd nanoparticles on the PAN-ACF caused the increase in the $SO_2$ adsorption performance by a catalytic action.

• Applied Chemistry for Engineering
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• v.28 no.1
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• pp.80-86
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• 2017

In this study, nitrogen functional groups were introduced on graphite fiber (GF) to modify their electrical properties, and heating properties were investigated according to the treatment conditions. GF was prepared by a thermal solid-state reaction at $200^{\circ}C$ for 2 h. Surface properties of the nitrogen doped GF were examined by XPS, and its resistance and heating temperature were measured using a programmable electrometer and thermo-graphic camera, respectively. The XPS result showed that the nitrogen functional groups on the GF surface were increased with increasing of urea contents, and the heating property of the GF was also improved as nitrogen functional groups were introduced. The maximum heating temperature of GF treated by urea was $53.8^{\circ}C$ at 60 V, which showed 55% improved heating characteristics compared to that of non-treated GF. We ascribe this effect to introduced nitrogen functional groups on the GF surface by thermal solid-state reaction, which significantly affects the heating characteristics of GF.

• Proceedings of the Korean Ceranic Society Conference
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• 2003.04a
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• pp.27.2-27
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• 2003

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.421-424
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• 2002

산업이 고도로 발달되고 공업화로 인한 자원 및 에너지의 무분별한 사용으로 산업전반에 걸쳐 배출되는 폐수 중에는 다양한 종류의 중금속 등이 포함되어 있어 사회적인 문제가 되고 있다. 특히, 환경을 고려하지 않은 화학물질의 남용은 폐수에 의한 수질의 중금속 오염을 가중시켜 왔으며, 이러한 중금속 중 크롬은 인간의 생리활성에 영향을 미치고 먹이사슬에 따라 축적되어 궁극적으로는 인간에게 질병을 유발시키는 중금속 중에 하나로서 국제사회로부터 커다란 관심을 불러 일으키고 있다[1]. (중략)

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1998.05a
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• pp.125-128
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• 1998

최근 많은 문제가 되고 있는 피혁공장, 유지공장, 슬러지처리장 등에서 발생하는 악취물질은 크게 산성 악취와 염기성 악취로 나눌 수 있으며, 대표적인 산성악취에는 메틸머켑탄, 황화수소가 있고, 염기성 악취는 암모니아, 트리메틸아민이 있다. 이들 악취물질들은 ACF의 표면을 화학약품으로 처리, 표면을 개질하여 관능기를 부여하고, 또한 화학물질을 첨착시켜 특정악취물질에 대한 제거효율을 증가시킬 수 있다. (중략)

• Applied Chemistry for Engineering
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• v.30 no.5
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• pp.580-585
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• 2019

In this study, we synthesized amine-functionalized magnesium-phyllosilicates (AF-MgP) with an octahedral and tetrahedral structure using (3-aminopropyl)triethoxysilane. The synthesis of AF-MgP, surface functionalization of amine and 1 : 2 ratio of the octahedral and tetrahedral structure were confirmed by FT-IR and XRD analysis. In addition, it was confirmed that AF-MgP was absorbed evenly on the surface of cotton fibers and coated on the cotton fibers from HR-SEM and EDX analysis. The antimicrobial activity test of cotton fibers according to KS confirmed that cotton fibers coated with AF-MgP particles show an enhanced antimicrobial activity against cutaneous microorganisms. Our results suggest that AF-MgP is not only applied as a functional nanomaterial that gives the cotton fiber antimicrobiality, but also can be used in the field of cosmetic and biomedical materials.

• Applied Chemistry for Engineering
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• v.27 no.5
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• pp.472-477
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• 2016

We studied the effects of anodic oxidation treatments of carbon fibers on interfacial adhesion of the carbon fibers-reinforced epoxy matrix composites with various current densities. The surface of treated carbon fibers was characterized by atomic force microscope (AFM), field emission-scanning electron microscope (FE-SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). The interlaminar shear strength (ILSS) of the composites was determined by a short beam shear test. This result showed that both the roughness and oxygen group of the carbon fibers surface increased in proportion to the current density. After anodic-oxidation-treated, the ILSS also increased as a function of the current density. In addition, the proportional relationship between ILSS and phenolic hydroxyl group was confirmed. The ILSS of the CF-2.0 sample increased by 4% compared to that of the CF-AS sample, because the anodic oxidation treatment increased the oxygen group and roughness on the carbon fibers surface, which leading to the improvement of the interfacial adhesion of the carbon fibers-reinforced epoxy matrix composites. Among these, the phenolic hydroxyl group which has the proportional relationship with ILSS is found to be the most important factor for improving the interfacial adhesion of the carbon fibers-reinforced epoxy matrix composites.