• 접착 및 계면
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• 제6권4호
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• pp.12-17
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• 2005

Natural fiber/phenolic biocomposites with chopped henequen fibers treated at various levels of electron beam irradiation (EBI) were made by means of a matched-die compression molding method. The interfacial property was explored in terms of interfacial shear strength measured by a single fiber microbonding test. The thermal properties were studied in terms of storage modulus, tan ${\delta}$, thermal expansion and thermal stability measured by dynamic mechanical analysis, thermomechanical analysis and thermogravimetric analysis, respectively. The result showed that the interfacial and thermal properties depend on the treatment level of EBI done to the henequen fiber surfaces. The present result also demonstrates that 10 kGy EBI is most preferable to physically modify the henequen fiber surfaces and then to improve the interfacial property of the biocomposite, supporting earlier results studied with henequen/poly (butylene succinate) and henequen/unsaturated polyester biocomposites.

• 대한전기학회논문지:시스템및제어부문D
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• 제52권5호
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• pp.206-206
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• 2003

It is hard to expect excellent electrical, mechanical and chemical properties from most of the composite materials presently used as insulators due to insufficient wettability property caused by the difference of interfacial properties between the matrix material and the reinforcer. Therefore, various interfacial coupling agents have been developed to improve the interfacial properties of composite materials. But if the wettable coupling agents are used outdoor for a long time, change in quality takes place in the coupling agents themselves, bringing about deterioration of the properties of the composite materials. In this study, glass surface was treated by plasma to examine the effect of dry interface treatment without coupling agent. It was identified that the optimum parameters for the best wettability of the samples at the time of generation of plasma were oxygen atmosphere, 0.1 torr of system pressure, 100 W of discharge power, and 3 minutes of discharge time. Also, the surface resistance rate and dielectric property were improved.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제52권5호
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• pp.206-212
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• 2003

It is hard to expect excellent electrical, mechanical and chemical properties from most of the composite materials presently used as insulators due to insufficient wettability property caused by the difference of interfacial properties between the matrix material and the reinforcer. Therefore, various interfacial coupling agents have been developed to improve the interfacial properties of composite materials. But if the wettable coupling agents are used outdoor for a long time, change in quality takes place in the coupling agents themselves, bringing about deterioration of the properties of the composite materials. In this study, glass surface was treated by plasma to examine the effect of dry interface treatment without coupling agent. It was identified that the optimum parameters for the best wettability of the samples at the time of generation of plasma were oxygen atmosphere, 0.1 torr of system pressure, 100 W of discharge power, and 3 minutes of discharge time. Also, the surface resistance rate and dielectric property were improved.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 일렉트렛트 및 응용기술
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• pp.31-35
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• 2002

It is hard to expect excellent electrical, mechanical and chemical properties from most of the composite materials presently used as insulators due to insufficient wettability property caused by the difference of interfacial properties between the matrix material and the reinforcer. Therefore, various interfacial coupling agents have been developed to improve the interfacial properties of composite materials. But if the wettable coupling agents are used outdoor for a long time, change in quality takes place in the coupling agents themselves, bringing about deterioration of the properties of the composite materials. In this study, composite materials were put to dry interfacial treatment by use of plasma technology. It has been presented that the optimum parameters for the best wettability of the samples at the time of generation of plasma were oxygen atmosphere, 0.1 torr of system pressure, 100 W of discharge power, and 3 minutes of discharge time. Also, the surface resistance rate and dielectric property were improved.

• Composites Research
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• 제34권5호
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• pp.305-310
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• 2021

섬유강화복합재료의 기계적물성은 섬유의 체적분율 및 사이징제 조건에 의한 계면강도에 영향을 받는다. 최적의 계면은 기지층에서 강화재로의 기계적 응력을 효과적으로 전달하여 응력 집중을 완화하고 결과적으로 복합재료의 성능을 향상시킬 수 있다. 본 논문에서는 사이징제 조건 및 섬유체적분율에 따른 에폭시 수지와 유리섬유 간의 젖음성 및 계면강도를 평가하였다. 정적 및 동적접촉각을 이용하여 사이징제가 다른 유리섬유와 에폭시 수지의 표면에너지를 계산하였고, 이를 활용하여 접착일을 계산하였다. 유리섬유 토우 캐필러리 시험법을 이용하여 젖음성을 평가하였고, 마이크로드롭렛 인발시험을 통해 계산된 계면전단강도를 이용하여 계면강도를 평가하였다. 최종적으로 젖음성과 계면강도를 활용하여 최적의 유리섬유강화 복합재료 제작 조건을 확인하였다.

• Transactions on Electrical and Electronic Materials
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• 제15권6호
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• pp.328-332
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• 2014

Thin film transistors (TFTs) with an amorphous silicon zinc tin oxide (a-2SZTO) channel layer have been fabricated using an RF magnetron sputtering system. The effect of the change of excitation electron on the variation of the total interfacial trap states of a-2SZTO systems was investigated depending on sputtering power, since the interfacial state could be changed by changing sputtering power. It is well known that Si can effectively reduce the generation of the oxygen vacancies. However, The a-2SZTO systems of ZTO doped with 2 wt% Si could be degraded because the Si peripheral electron belonging to a p-orbital affects the amorphous zinc tin oxide (a-ZTO) TFTs of the s-orbital overlap structure. We fabricated amorphous 2 wt% Si-doped ZnSnO (a-2SZTO) TFTs using an RF magnetron sputtering system. The a-2SZTO TFTs show an improvement of the electrical property with increasing power. The a-2SZTO TFTs fabricated at a power of 30 W showed many of the total interfacial trap states. The a-2SZTO TFTs at a power of 30 W showed poor electrical property. However, at 50 W power, the total interfacial trap states showed improvement. In addition, the improved total interfacial states affected the thermal stress of a-2SZTO TFTs. Therefore, a-2SZTO TFTs fabricated at 50 W power showed a relatively small shift of threshold voltage. Similarly, the activation energy of a-2SZTO TFTs fabricated at 50 W power exhibits a relatively large falling rate (0.0475 eV/V) with a relatively high activation energy, which means that the a-2SZTO TFTs fabricated at 50 W power has a relatively lower trap density than other power cases. As a result, the electrical characteristics of a-2SZTO TFTs fabricated at a sputtering power of 50 W are enhanced. The TFTs fabricated by rf sputter should be carefully optimized to provide better stability for a-2SZTO in terms of the sputtering power, which is closely related to the interfacial trap states.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2007년도 추계학술발표회
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• pp.61-62
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• 2007

• 대한화장품학회지
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• 제22권2호
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• pp.167-173
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• 1996

The stability of gel structured emulsion and the effect of polyols on it have been studied by rheological property and interfacial tension. In this paper, three types of gel structured emulsions were prepared by using three polyols respectively(glycerine for sample 1, 1.3 BG for sample 2, PG for sample 3). And both complex modulus($G^*$) and loss angle[$\delta$ = tan-1(G"/G')] of samples were investigated against oscillating shear stress and frequency($\omega$). The results show sample 1 is most highly consistent with oscillating shear stress. And the results were compared with those of accelerated tests concerning storage stability of gel structured emulsion. To correlate consistency of rheological property with storage stability, interfacial tension from which adsorption efficiency of surfactant(Octyldodecyl Ether) could be known was measured. Sample 1 showed the largest value of [$d{\gamma}/dIn_{Cconc. of surfactant}$] in Gibbs equation. In summary, the prediction of stability could be correctly made by the consistency of rheological property(G*,$\gamma$) of gel structured emulsion against oscillating shear stress and it could be supported by measuring interfacial tension. And polyol affected the value of [$d{\gamma}/dIn_{Cconc. of surfactant}$], consequently affected the stability.lity.

• 접착 및 계면
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• 제23권3호
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• pp.87-93
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• 2022

섬유와 기지 간 계면 특성을 분석하기 위해 일반적으로 접촉각을 활용하여 계산된 접착일을 활용한다. 접촉각 측정 방식으로 동적접촉각과 정적접촉각이 있으며, 본 논문에서는 보다 정확도가 높은 접촉각 측정 방법이 무엇인지 모색하였다. 각각 4가지 종류의 에폭시 수지와 유리섬유를 사용하였고, 유리섬유와 에폭시의 표면 에너지 결과를 기반으로 접착일, W_a을 계산하여 계면강도를 예측하였다. 접착일과 계면 전단강도는 이론상 비례관계이며, 이를 확인하기 위해 조성이 다른 에폭시와 유리섬유 간의 계면강도를 마이크로드롭렛 시험법을 이용하여 측정하였다. 정적접촉각 결과의 경우 접착일과 계면 전단강도 사이에는 일치하지 않는 경향을 보였다. 이는, 동적 접촉각 평가 방법은 정적접촉각에 비해, 드롭 크기에 따른 최소 표면적을 이루는 에러와 미니스커서에서 접선 측정에 따른 에러를 최소화할 수 있다는 점이다.

• Korean Membrane Journal
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• 제4권1호
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• pp.12-19
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• 2002

Nanofiltration of aqueous dye solutions was carried out using polyamide (PA) nanofiltration (NF) composite membranes. The PA composite membranes were prepared by the interfacial polymerization of piperazine (PIP) and trimesoyl chloride (TMC) on the surface of microporous polysulfone (PSf) ultrafi1tration (UF) membranes. After characterization in terms of their permeation performance and surface ionic property, they were used for the separation of dye solutions such as Direct Red 75, 80, 81, and Direct Yellow 8 and 27. The separation conditions were varied to study the factors affecting on the permeation performance of the membranes: different concentrations of dye solutions, operating temperature and time, and flow rate of a feed solution. The surface property of the membrane, especially its ionic property, as a function of operating time was examined with a zeta-potentiometer and the relationship between the surface chemistry of the membrane and its permeation properties was also studied.