• 한국진공학회:학술대회논문집
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• 한국진공학회 1999년도 제17회 학술발표회 논문개요집
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• pp.160-160
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• 1999

To reduce the fouling of heat exchangers, the plasma polymerized films was coated on the heat exchangers, and an effect of plasma polymerized film on fouling of heat exchangers was investigated. Monomer and reactive gases were used as the precursors of plasma polymerization. Plasma polymerized films were deposited with process parameters of pressure, power, and ratio of gases. Plasma polymerized films could be served as functional layers of good wettability and high resistance to corrosion. Wettability of plasma polymerized film could be controlled by the ratio change gas mixture. Hydrophilicity of plasma polymerized films on heat exchanger in air conditioner can provide improvement in performance of heat exchanger which results from good water drainage, decrease of pressure drop. DC-plasma polymerized films improve resistance to corrosion whcih is related to deposit formation in heat exchangers. The difference in the build up of fouling deposits between bare substrate and plasma polymerized substrate was investigated by scanning electron microscopy (SEM). An effect of plasma polymerized film on fouling of heat exchangers was discussed in terms of surface properties such as wettability, surface chemical state.

• 한국표면공학회지
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• 제36권1호
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• pp.9-13
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• 2003

Plasma polymerized organic thin films were deposited on Si(100), glass and metal substrates at $25∼100 ^{\circ}C$ using thiophene and toluene precursors by PECVD method. In order to compare physical and electrochemical properties of the as-grown thin films, the effects of the RF plasma power in the range of 30∼100 W and deposition temperature on both corrosion protection efficiency and physical properties were studied. We found that the corrosion protection efficiency ($P_{k}$), which is one of the important factors for corrosion protection in the interlayer dielectrics of microelectronic devices application, was increased with increasing RF power. The highest $P_{k}$ value of plasma polymerized toluene film (85.27% at 70 W) was higher than that of the plasma polymerized thiophene film (65.17% at 100 W), indicating inhibition of oxygen reduction. The densely packed and tightly interconnected toluene film could act as an efficient barrier layer to the diffusion of molecular oxygen. The result of contact angle measurement showed that the plasma polymerized toluene films have more hydrophobic surface than those of the plasma polymerized thiophene films.

• 공업화학
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• 제32권1호
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• pp.49-54
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• 2021

메틸 메타크릴레이트 분자를 전구체로 사용하여 원격 플라즈마 방식으로 중합체를 합성하는 반응에서 플라즈마 출력, 반응 압력 및 직접-간접 플라즈마 방식이 필름의 성장속도 및 화학결합 구조에 미치는 영향을 조사하였으며, FT-IR, XPS 등 분광학적 분석과 Langmvir 탐침을 사용한 플라즈마 특성 진단 결과와 함께 고찰하였다. 플라즈마 출력과 반응 압력이 증가하면 성장속도가 증가하지만 특정 영역을 넘어서면 식각 효과와 잦은 충돌로 인해 활성화 효율이 낮아져 다시 감소하였다. 중합 필름의 FT-IR과 XPS 분석 결과, 필름 내 탄소/산소 조성비는 플라즈마 출력이 커질수록 증가하였으며, 탄화수소성 C-C 탄소 조성비는 증가하는 반면 에스터성 COO 탄소 조성비는 감소하였다. 직접 플라즈마법이 간접 플라즈마법에 비해 필름의 성장속도는 2~5배 빠르지만, 전구체의 분자 구조를 유지하기 위해서는 간접 플라즈마법이 유리함을 확인하였다.

• 대한소아치과학회지
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• 제29권2호
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• pp.262-269
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• 2002

본 연구는 할로겐광과 비교하여, 고강도의 단축된 중합 시간을 장점으로 하는 플라즈마광의 효율성을 평가할 목적으로, 첫째, 중합 시간과 중합 거리에 따른 중합도의 변화를 검토, 광조사 시간을 증가시킬 경우 특정거리 이상에서도 수복물 하층까지 충분한 중합이 이루어지는지 알아보고, 둘째, 중합 반경에 따라 균일한 중합이 이루어지는지 보기 위해 광조사 부위의 중심부와 외측 변연부의 중합도 차이를 비교하였다. 2mm 두께의 복합레진 시편의 상 하면 미세경도 측정을 통해 중합도를 비교해 본 결과, 다음과 같은 결론을 얻었다. 1. 거리증가에 따른 상대광도의 감소는 할로겐광에 비해 플라즈마광에서 그 차이가 적었다(p<0.05). 2. 플라즈마광, 할로겐광 모두 상면의 미세경도는 중합거리 2mm 이상부터 유의하게 감소되었으며, 중합시간의 증가에 따라 증가되었다(p<0.05). 3. 플라즈마광 3초를 제외하고, 하면의 미세경도 변화는 4mm 이상에서 급격히 감소하였으며, 상면에 비해 중합시간과 거리의 영향을 많이 받았다(p<0.05). 4. 플라즈마광, 할로겐광 모두 조사시간의 증가에도 불구하고 4mm와 6mm 사이에서 하면의 미세 경도차는 비교적 크게 나타났다(p<0.05). 5. 플라즈마광을 $6{\sim}9$초 적용한 때와 할로겐광을 $40{\sim}80$초 적용한 때의 미세경도치 및 거리에 따른 경도 변화는 유사하였다(p>0.05). 6. 플라즈마광, 할로겐광 모두 레진 시편의 중앙에서 외측으로 갈수록 미세경도는 유의하게 감소하였다(p<0.05).

• Journal of Electrical Engineering and Technology
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• 제6권6호
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• pp.836-841
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• 2011

Plasma polymerized methyl methacrylate (ppMMA) thin films were deposited by plasma polymerization technique with different plasma powers and subsequently thermally treated at temperatures of 60 to $150^{\circ}C$. To find a better ppMMA preparation technique for application to organic thin film transistor (OTFT) as dielectric layer, the chemical composition, surface morphology, and electrical properties of ppMMA were investigated. The effect of ppMMA thin-film preparation conditions on the resulting thin film properties were discussed, specifically O-H site content in the pMMA, dielectric constant, leakage current density, and hysteresis.

• 한국염색가공학회지
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• 제10권2호
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• pp.8-17
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• 1998

In this study we have examined electroless chemical plating on the plasma grafted poly [ethylene terephathalate］(PET) fabric in order to improve the interfacial adhesion between metal and fiber. The vapour phase of acrylic acid introduced on the PET surface and the graft polymerization was carried out by using cold plasma, resulting in the grafting yield of 0.8-1.3 wt％. The carboxyl group of the plasma grafted was identified by FT-IR-ATR spectra. The Interfacial adhesion was related to the carboxyl group. After electroless chemical plating of nickel, it showed that the more the carboxyl, the better the interfacial adhesion. Comparing to the untreated, the plasma grafted fabric showed fairly good interfacial adhesion(5B grade, ASTM D3359) . The shielding effect of electromagnetic wave showed 95dB. The shielding effect depends on the fabric structure, the surface structure, and the cross sectional shape of fibers. The dense fabric structure, the etched surface like a microcrater, and the trigonal cross sectional shape were prefered.

• 한국염색가공학회지
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• 제34권3호
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• pp.165-172
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• 2022

Polypropylene(PP) is a textile material with various functions such as eco-friendliness, lightness, and elasticity. Although most synthetic fibers can be dyed and finished, but original PP is difficult to dye or finish due to its extremely hydrophobic properties, so its application expansion is limited. In order to solve this problem, dyeable PP was developed, and various researches on textiles for clothing such as mass production technology, fine fiberization and performance improvement are in progress. Plasma treatment is a processing method for modifying the surface of fabrics, and has effects such as hydrophilization, deepening color, improving adhesion, and surface polymerization. In this study, plasma treatment was applied to study changes in hydrophilization properties of dyeable PP, surface changes before and after plasma treatment and performance according to hydrophilization.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1991년도 하계학술대회 논문집
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• pp.198-200
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• 1991

In this study we fabricated thin organic polymer films on the comb-electrode by plasma polymerization methode in electrode gas flow type reactor. The dielectric constant of polymer films were increased by increasing relative humidity and we used free volume theory in order to explain the mechanism of water absorption phenomena of polymer films.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1993년도 추계학술대회 논문집
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• pp.131-133
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• 1993

Plasma polymerized thin films were prepared using an interelectrode capacitively coupled gas flow type reactor. Hexamethyldisiloxane was chosen as the monomer to be used. The dielectric properties of the thin films have been investigated with the changes of discharge power, heat treatment temperature and frequency. The relative dielectric constant was increased with an increasing of discharge power, but was decreased with an increasing of heat treatment temperature.

• Membrane and Water Treatment
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• 제4권2호
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• pp.109-126
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• 2013

Surface modification by low-pressure ammonia ($NH_3$) plasma on commercial thin-film composite (TFC) membranes was investigated in this study. Surface hydrophilicity, total surface free energy, ion exchange capacity (IEC) and zeta (${\zeta}$)-potentials were determined for the TFC membranes. Qualitative and quantitative analyses of the membrane surface chemistry were conducted by attenuated total reflectance Fourier transform infrared (ATR FT-IR) spectroscopy. Results showed that the $NH_3$ plasma treatment increased the surface hydrophilicity, in particular at a plasma treatment time longer than 5 min at 50 W of plasma power. Total surface free energy was influenced by the basic polar components introduced by the $NH_3$ plasma, and isoelectric point (IEP) was shifted to higher pH region after the modification. A ten (10) min $NH_3$ plasma treatment at 90 W was found to be adequate for the TFC membrane modification, resulting in a membrane with better characteristics than the TFC membranes without the modification for water treatment. The thin-film chemistry (i.e., fully-aromatic and semi-aromatic nature in the interfacial polymerization) influenced the initial stage of plasma modification.