• Elastomers and Composites
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• 제39권1호
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• pp.3-11
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• 2004

플라즈마 표면처리는 표면 관능기 표면 활성도 등을 증가시켜 촉매적 선택성, 염색성 및 다양한 소재의 접착력을 증가시켜주는데 큰 역할을 담당한다. 본 연구에서는 dielectric barrier discharge (DBD)를 이용한 상압 플라즈마 토치로 ethylene-vinyl acetate (EVA)의 표면을 처리하였다. 이때 사용된 가스는 아르곤, 공기, 및 산소를 이용하였으며, 표면처리에 따른 EVA의 표면 특성을 제타전위와 표면자유에너지를 이용하여 관찰하였다. 그 결과, 상압 플라즈마 표면처리에 따른 EVA의 표면 관능기는 접착 에너지 ($G_{IC}$)와 비례관계를 가지며 증가하는 것을 확인하였다. 특히, 상압 플라즈마 표면처리 공정은 EVA와 polyurethane (PU) 계면의 접착력을 크게 증가시켜 주는 것을 확인하였다.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2014년도 추계학술대회 논문집
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• pp.199-199
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• 2014

좁은 관경을 갖는 상대 유전율 3 이하인 PTFE와 PE 고분자 튜브 내부에 플라즈마 방전을 일으켜 고분자 튜브 표면 그래프팅 기술을 개발 하고자 하였다. 스텐트 및 인공혈관 등에 적용이 가능한 내부지름 3 mm 이하의 원통형 고분자 생체 식립체 내부 표면을 그래프팅하는 기술이다. 좁은 고분자 튜브 내부에 생성되는 방전은 고분자의 관경에 의해 방전개시 전압이 결정되었다. 방전개시 이후 DC glow discharge 에서 나타나는 전압과 전류의 특징들이 나타났다. 전압과 전류의 파형 분석에서는 고분자 표면과 가스 간의 새로운 용량성 임피던스가 형성되는 것을 관찰하였다. 고분자 내부 표면에 플라즈마의 방전 형태는 면 방전 (surface discharge)의 형태로 나타났다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.2193-2195
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• 2005

The hybrid discharge reactor was designed for the application of wastewater treatment and the removal of hazardous volatile organic substances in water. This discharge type was similar to the barrier discharge, and the surface discharge on the dielectric surface was propagated to the water surface. That caused the heterogeneous chemical reaction strongly at the interface between the working gases and the water surface. Changes of the conductivity, acidity, and the dissolved ozone with respect to the treatment time and water quantities were studied as the fundamental experiment. The concentration of hydrogen ions largely increased with increasing the treatment time and the conductivity increased with respect to the increase of water quantities under the constant other discharge parameters.

• Transactions on Electrical and Electronic Materials
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• 제12권3호
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• pp.110-114
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• 2011

Polymeric films of high chemical stability and mechanical strength covered with a thin metallic film have been extensively used in various fields as electric and electronic materials. In this study, we have chosen polypropylene (PP) as the polymer due to its outstanding chemical resistance and good creep resistance. We coated thin nickel film on PP films by the electroless plating process. The surfaces of PP films were pre-treated and modified to increase the adhesion strength of metal layer on PP films, prior to the plating process, by an environment-friendly process with atmospheric plasma generated using dielectric barrier discharges in air. The surface morphologies of the PP films were observed before and after the surface modification process using a scanning electron microscope (SEM). The static contact angles were measured with deionized water droplets. The cross-sectional images of the PP films coated with thin metal film were taken with SEM to see the combined state between metallic and PP films. The adhesion strength of the metallic thin films on the PP films was confirmed by the thermal shock test and the cross-cutting and peel test. In conclusion, we made a composite material of metallic and polymeric films of high adhesion strength.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2007년도 춘계학술발표회 초록집
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• pp.82-83
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• 2007

DBD type을 이용한 remote plasma에서 발생된 대기압 플라즈마를 이용하여, PR에 대한 식각 실험을 진행하였다. 과거 습식 화학적 공정에서 오던 기술적 제한의 극복과 진공 플라즈마 가지는 단점을 극복하기 위해 대기압 플라즈마를 이용한 건식 세정에 관한 연구를 진행하였고, 이 때 Gas는 $N_2/O_2$+$SF_6$ 의 조합으로 사용하였으며, 각 gas의 유량에 다른 remote 플라즈마의 전기적, 광학적 특성에 대해 관찰하였다.

• 폴리머
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• 제29권6호
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• pp.581-587
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• 2005

상업용 폴리우레탄(PU) 필름의 표면 개질 목적으로 대기압에서 플라스마를 발생시키기 위한 dielectric barrier discharge(DBD) 구조의 평판형 플라스마 반응기 내에서 이온화된 아르곤 플라스마를 사용하였다. 플라스마 처리 공정변수인 처리 시간, 처리 RF-power, 아르곤 가스 유속을 변화시켜가며 접촉각을 측정하여 젖음성과 표면 자유 에너지 변화를 알아보았고, 필름 표면 위에 과산화물을 최대로 도입시키기 위해 플라스마 처리 공정변수를 최적화하였다. 대기압 플라스마 처리 시간 70초, RF-power 120 W, 아르곤 가스유속 6 liter per minute(LPM)에서 가장 높은 젖음성과 표면 자유 에너지 값을 보였고, 1,1-diphenyl-2-picrylhydrazy(DPPH) 법을 사용하여 PU 필름의 표면에 생성된 과산화물의 농도를 정량한 결과, 처리 시간 30초, RF-power 80 W, 아르곤 가스유속 6 LPM의 플라스마 처리 조건에서 최대 2.1 nmol/$\cm^{2}$의 과산화물이 생성되었다.

• Journal of Ginseng Research
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• 제45권4호
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• pp.519-526
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• 2021

Background: This study aimed to investigate the effect of cold plasma treatment on the improvement of seed germination and surface sterilization of ginseng seeds. Methods: Dehisced ginseng (Panax ginseng) seeds were exposed to dielectric barrier discharge (DBD) plasma operated in argon (Ar) or an argon/oxygen mixture (Ar/O₂), and the resulting germination and surface sterilization were compared with those of an untreated control group. Bacterial and fungal detection assays were performed for plasma-treated ginseng seeds after serial dilution of surface-washed suspensions. The microbial colonies (fungi and bacteria) were classified according to their phenotypical morphologies and identified by molecular analysis. Furthermore, the effect of cold plasma treatment on the in vitro antifungal activity and suppression of Cylindrocarpon destructans in 4-year-old ginseng root discs was investigated. Results: Seeds treated with plasma in Ar or Ar/O₂ exhibited a higher germination rate (%) compared with the untreated controls. Furthermore, the plasma treatment exhibited bactericidal and fungicidal effects on the seed surface, and the latter effect was stronger than the former. In addition, plasma treatment exhibited in vitro antifungal activity against C. destructans and reduced the disease severity (%) of root rot in 4-year-old ginseng root discs. The results demonstrate the stimulatory effect of plasma treatment on seed germination, surface sterilization, and root rot disease suppression in ginseng. Conclusion: The results of this study indicate that the cold plasma treatment can suppress the microbial community on the seed surface root rot in ginseng.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 학술대회 논문집 전문대학교육위원
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• pp.29-32
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• 2000

Ozone has been widely applied to many industrial fields because of its strong oxidation effects. Therefore, the studies have been progressed for the effective and high concentration of one generation. The silent or surface discharge have been mainly used for high concentration ozone generation until now. But these two types of ozone generators have shortcomings to be improved. In this study, the ozone generator which improved the shortcomings of above two type of ozone generators was proposed and manufactured for high concentration ozone generation. And the proposed ozone generator could generate the surface and barrier discharge simultaneously. For this purpose, a mesh type discharge electrodes were proposed and the experiments were fulfilled as a function of the widths and spacings of mesh electrodes and gap spacings between the dielectric barrier and mesh electrode. When the width of mesh electrode[WM] and spacing of mesh electrode[SM] are 0.3[mm] and 0.8[mm] respectively, the maximum ozone concentration of 2.96[vol%] was obtained at 5.6[kV], 830[mA], gap spacing (S)=0.65[mm].

• 공업화학
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• 제33권2호
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• pp.229-233
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• 2022

In this study, a gas-liquid hybrid atmospheric pressure plasma reactor of the dielectric barrier discharge method was fabricated and characterized. The solubility of copper oxide in the organic acid solution was increased when argon having a larger atomic weight than helium was used during plasma discharge. There was no significant effect of mixing organic acid solutions under plasma discharge treatment on the variation of copper oxide's solubility. As the applied voltage for plasma discharge and the concentration of the organic acid solution increased, the dissolution and removal power of the copper oxide layer increased. Solubility of copper oxide was more affected by the concentration in organic acid solution rather than the variation of plasma applied voltage. The usefulness of hybrid plasma reactor for the surface cleaning process was confirmed.

• 한국환경과학회지
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• 제30권5호
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• pp.399-406
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• 2021

The dissolution of ionized gas in dielectric barrier plasma, similar to the principle of ozone generation, is a major performance-affecting factor. In this study, the plasma gas dissolving performance of a gas mixing-circulation plasma process was evaluated using an experimental design methodology. The plasma reaction is a function of four parameters [electric current (X₁), gas flow rate (X₂), liquid flow rate (X₃) and reaction time (X₄)] modeled by the Box-Behnken design. RNO (N, N-Dimethyl-4-nitrosoaniline), an indictor of OH radical formation, was evaluated using a quadratic response surface model. The model prediction equation derived for RNO degradation was shown as a second-order polynomial. By pooling the terms with poor explanatory power as error terms and performing ANOVA, results showed high significance, with an adjusted R² value of 0.9386; this indicate that the model adequately satisfies the polynomial fit. For the RNO degradation, the measured value and the predicted values by the model equation agreed relatively well. The optimum current, gas flow rate, liquid flow rate and reaction time were obtained for the highest desirability for RNO degradation at 0.21 A, 2.65 L/min, 0.75 L/min and 6.5 min, respectively.