• 한국재료학회지
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• 제7권8호
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• pp.650-653
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• 1997

In large generators in power plants, stator winding insulations is exposed to a combination of thermal, electrical, mechanical, environmental stresses in service. These combined stresses cause insulation aging which leads to final insulation breakdown. In order to identify the breakdown mechanism, the stator winding insulation materials which are composed of mica-epoxy is analyzed by the component of materials with EDS, SEM techniques. We concluded that the potassium ions of mica are replaced by hydrogen ions at boundary area of mica-epoxy and/or mica-mica. It is proposed that through these phenomena, the conductive layers of potassium ions enable high voltage fields of multiple stresses to create voids and microcracks.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.69-69
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• 2010

Carbon nano tubes (CNTs) have been attractive candidates for fundamental research studies due to their outstanding physical and chemical properties. High thermal and chemical stability and large surface area make CNTs an ideal platform for many nano materials systems. Several applications such as Several applications were proposed for CNTs many of which are concerned with conductive or high strength composites make them excellent candidates for a variety of energy conversion and storage technologies.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2003년도 추계학술발표대회 논문집
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• pp.234-237
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• 2003

The absorption and the interference shielding of the electromagnetic wave problem have been a very important issue for commercial and military purposes. This study dealt with the simulation reflection loss for electromagnetic absorbing sandwich type structures in X-band(8.2Ghz~12.4GHz). Glass/epoxy composites containing conductive carbon blacks were used for the face sheets and styrofoams were used for the core. Their permittivities in X-band were measured using the transmission line technique. Simulation results of 3-1ayered sandwich type structures showed the reflection loss using the theory about transmission and reflection in a multi-layered medium.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2001년도 가을 학술발표회 논문집
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• pp.29-32
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• 2001

Conductive polymers(CPs) are a relatively new class of organic materials displaying as their foremost property a high conductivity combined with very light weight, flexibility and reasonably facile processability[1]. Due to their high conductivity/weight ratio, they have recently evinced much interest in potential application as EMI shielding screens, coatings or jackets for flexible conductors, rechargeable batteries and as possible substitutes for metallic conductors or semiconductors in wide variety of electrical devices[2]. (omitted)

• 대한전기학회논문지
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• 제37권1호
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• pp.55-62
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• 1988

The variation of electrical resistivity of silver particle-filled polymers with the volume percent of silver particles was investigated. Also, the relationships between the surface tension of polymer and dispersion effect of silver particles were studied to find the steep drop of electrical resisivity, in view of agglomerate morphology. The critical volume precent of silver particles varied depending on the polymer species and increased with the increasing surface tension of polymer. The steep variation of resistivity with the increasing temperature was explained with the expansion of polymer at the melting temperature of polymer. The conductive break down current increased with the increasing volume percent of silver particles in the Ag/LDPE system and that was attributed to heat of Joule taken througn the contact area between the silver particle.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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• pp.1410-1411
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• 2006

To improve density and smoothness of semiconducting materials in power cable, we have investigated those of semiconducting materials showed by changing the content of carbon black and Carbon Nanotube. They were produced as sheets after pressing for 20 minutes at $180[^{\circ}C]$ with a pressure of $200[kg/cm^2]$. The content of conductive carbon black and Carbon Nanotube were 30[wt%] and 2-6[wt%] respectively. As a result the smoothness was measured by JSM-6400.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.1887-1889
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• 2005

To measure the mechanical and structural properties of semiconducting materials in power cable, we have investigated the stress-strain and fractural structure of semiconducting materials showed by changing the content of carbon black. Those were made as sheets after pressing for 20 minutes at $180[^{\circ}C]$ with a pressure of $200[kg/cm^2]$. The contents of conductive carbon black were 20, 30 and 40(wt%), respectively. The stress-strain experiment was measured by TENSOMETER 2000. The SEM experiment was measured by JSM-6400. From above experimental result, Strain was decreased, while stress was increased according to increment of carbon black content. EEA among resins was best the dispersion of carbon back in base resin from SEM measurement.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.218-219
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• 2006

To Smoothness of semiconducting materials in power cable, we have investigated those of semiconducting materials showed by changing the content of carbon black and Carbon Nanotube. Then they were produced as sheets after pressing for 20 minutes at $180^[{\circ}C]$ with a pressure of $200[kg/cm^2]$. The content of conductive carbon black and Carbon Nanotube was the variable, and their contents were 20-40[wt%] and 2-6[wt%] respectively. The smoothness was measured by JSM-6400.

• Elastomers and Composites
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• 제56권3호
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• pp.117-123
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• 2021

Electronic skin (or E-skin) is an artificial smart skin composed of one or more than two sensors. E-skins detect external stimuli and convert them into electrical signals. Various types of E-skin sensors exist, including mechanical, physical, and chemical, depending on the detection signals involved. For wearable E-skins with superior sensitivity and reliability, developing conductors that possess both good elasticity and sensitivity is essential. Typical electrical conductors used in these sensors show very high sensitivity, but they have drawbacks such as non-linearity, irreversibility, and a narrow sensing range. To address these issues, stretchable and lightweight ionic conductors have been actively used in E-skin applications. This study summarizes the recent progress on various types of ionic conductors and ionic-conductor-based E-skin sensors.

• 공업화학
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• 제23권4호
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• pp.372-376
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• 2012

탄소나노튜브는 좋은 전기 기계적 및 열적 특성을 가진 복합 재료 분야에서 가장 이상적인 나노 충전재이다. 따라서 탄소나노튜브의 복합 재료는 전도성 재료, 고강도를 가지면서 가벼운 무게를 가지는 재료에 이용된다. 탄소나노튜브 복합재료의 주요 문제점은 탄소나노튜브의 나쁜 분산에 있다. 본 연구에서는 다중벽 탄소나노튜브(MWNT)를 물리적 방법으로 전처리하였다. 전처리 후, 고분자/MWNT nanocomposites는 용해 공정에 의해 분산되었다. 물리적 방법은 고분자 wrapping 방법에 의해 준비되었다. ABS/MWNT 복합 재료의 기계적 및 전기적 특성을 SAN과 함께 wrapping된 MWNT와 미처리된 MWNT와 혼합된 ABS의 속성을 비교하여 연구하였다. MWNT가 wrapping된 복합체의 인장강도는 증가하였으나 충격강도는 감소한 수치를 보였다. 전기적 물성의 향상에는 미처리시료와 비교해 볼 때 큰 효과가 없었다.