• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.387-387
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• 2009

In the study the volume resistivity Characteristics of epoxy resin using nanocomposites, nano-comosites are made from insulating material epoxy resin using for power transformer equipment and molding several devices as changing amount of addition of diameter 12 [nm] $SiO_2$, we measured volume resistivity of nano-composites by High Resistance Meter(4329A). As the result of measurement, we have seen the epoxy resin using 1.6 [wt%] nanocomposites was the highest measured at the volume resistivity, and using 0.4 [wt%] nanocomposites was highest stabilized than others according to variable temperature properties.

• 한국분말재료학회지
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• 제5권4호
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• pp.334-339
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• 1998

In purpose of introducing the inverse magnetostrictive properties into the structural ceramics, $Al_2O_3$ based nanocomposites dispersed with nano-sized Ni-Co particles were studied. The composites were fabricated by the hydrogen reduction and hot-pressing of $Al_2O_3$ and NiO-CoO mixed powders. The mixtures were prepared by using Ni- and Co-nitrate $(Ni(NO_3)_2\;{\cdot}\;6H_2O\;and\;Co(NO_3)_2\;{\cdot}\6H_2O)$ as source materials for the Ni-Co particles. Microstructural observations revealed that nano-sized Ni-Co particles were dispersed homogeneously at $Al_2O_3$ grain boundaries. High strength above 1 GPa was obtained for the $Al_2O_3/10$ wt% Ni-Co nanocomposite fabricated by a controlled powder preparation process. The inverse magnetostrictive response to applied stress was obtained due to the presence of dispersed Ni-Co particles, which indicates a possibility to incorporate new functions into the structural ceramics without loosing the mechanical properties.

• 반도체디스플레이기술학회지
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• 제12권1호
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• pp.23-28
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• 2013

Epoxy resins are widely used in microelectronics packaging such as printed circuit board and encapsulating for semiconductor manufacturing. Water can diffuse into and through the epoxy matrix systems and moisture absorption at boarding interfaces of matrix resin systems can lead to a hydrolysis at the interfaces resulting in delamination of encapsulating materials. In the study, the changes of diffusion coefficient and moisture content ratio of epoxy resin systems with nano-sized fillers according to the change of liquid type epoxy resins were investigated. RE-304S, RE-310S, RE-810NM and HP-4032D as a epoxy resin, Kayahard AA as a hardener, and 1B2MI as a catalyst were used in these epoxy resin systems. After curing, moisture content ratios were measured with time under the 85 and 85% relative humidity condition using a thermo-hydrostat. The maximum moisture absorption ratio and diffusion coefficient of EMC decrease with the filler content. It can be seen that these decreases are due to the increase of filler surface area and the decrease of moisture through channel with the content of nano-sized filler.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.92-92
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• 2010

In this paper, the test is performed on MgO, which is used as a filler in epoxy additives, respectively (0, 1.0, 3.0, 5.0, 7.0, 10 [wt%]) for HVDC(high voltage direct current) submarine cable insulating material to improve electrical properties of epoxy resin in high temperature. The breakdown strength due to increasing amount of filler increased to 5.0 [wt%] by the effects of the Coulomb blockade. However, it is confirmed that strength of dielectric breakdown decreased because the filler functioned as impurities and affected the breakdown when filler additive exceeded by 5.0 [wt%] or more. We have found that the highest dielectric breakdown strength of specimen added 5.0 wt% at $25^{\circ}C$, and is more increased approximately 13.7 [%] than virgin specimen.

• Carbon letters
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• 제9권4호
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• pp.294-297
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• 2008

A CNT-$TiO_2$ nano composite was prepared from titanium chloride ($TiCl_4$) via sol-gel process using multi walled carbon nano tube (MWCNT) followed by calcination at $450^{\circ}C$. Spectral analysis revealed that the formed $TiO_2$ resided on the carbon in anatase form. The effect of adsorption was investigated using aqueous solution of methylene blue and procion blue dye. The photochemical reaction of CNT-$TiO_2$ composite in aqueous suspensions was studied under UV illumination in batch process. The reaction was investigated by monitoring the discoloration of the dyes employing UV-Visible spectro-photometeric technique as a function of irradiation time. The catalyst composites were found to be efficient for the photodegradation of the dye.

• Composites Research
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• 제31권4호
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• pp.171-176
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• 2018

인공 건식 접착 구조를 위한 새로운 마이크로-나노 계층구조 제작기법을 제안하였으며, 모세관법을 활용한 마이크로 구조 내 나노 소재 정렬에 대한 기초 연구를 수행하였다. 다중 벽 탄소나노튜브(MWCNT)와 폴리디메틸실록산(PDMS) 혼합물의 제작 조건에 따른 경화도 및 점도 특성을 분석하고, 이로부터 몇 가지 제작 조건을 결정하였다. MWCNT-PDMS 마이크로 구조 제작 후 단면 분석을 통해 PDMS내 MWCNT의 정렬 특성을 분석한 결과, 제작 온도와 상대 경화도가 낮을 경우 MWCNT의 정렬도가 우수하며, 단위 면적당 MWCNT의 밀도는 제작 온도나 상대 경화도에 영향을 적게 받는 것으로 확인되었다.

• Composites Research
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• 제17권5호
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• pp.68-77
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• 2004

레이더 혹은 전자-통신장비에서 방출되는 전자파의 흡수/차폐는 군사적인 목적뿐만 아니라 상업적 목적으로도 매우 중요하다. 효과적인 전자기파 흡수체를 설계하기 위해서는 흡수체에 사용되는 재료의 대상 주파수 대역에서의 전자기적 성질을 정확히 알아야 하며, 손실재의 함량에 따른 정확한 전자기물성 예측이 가능해야 한다 본 연구에서는 전도성 카본 블랙 나노 입자를 함유하는 폴리에스터 복합재료의 유전성질을 자유공간 기법을 이용하여 X-Band 주파수 대역에 걸쳐 측정하고 카본 블랙의 함량에 따라 정량적으로 분석하였으며, 임의의 카본 블랙 함량을 갖는 고분자 수지의 유전 물성을 주파수에 따라 예측할 수 있는 방법을 제시하고 검증하였다.

• Transactions on Electrical and Electronic Materials
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• 제13권6호
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• pp.267-272
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• 2012

Considering the properties of the carbon nano tubes (CNT), their inclusion into the polymer matrix vastly increases the properties of the resultant composite. However, this is not the case due to the poor interfacial adhesion of the CNT and the polymer matrix. The present approach focuses on increasing the interaction between the polymer matrix and the CNT through the chemical modification of the CNT resulting in allyl ester functionalized carbon nanotubes (ACNT) and silane functionalized carbon nano tubes (SCNT) which are capable of reacting with the polymer matrix during the curing reaction. The addition of ACNT/SCNT into unsaturated polyester resin (UPR) resulted in the improvement of the electrical properties of resulted nanocomposites in comparison to the CNT. The surface resistivity, volume resistivity, dielectric strength, dry arc resistivity, and the comparative tracking index of the nanocomposites were significantly improved in comparison to CNT. The chemical modification of CNT was confirmed via spectroscopy.

• 한국재료학회지
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• 제13권4호
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• pp.213-218
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• 2003

Fibrous monolithic control of$ Al_2$$O_3$ -$ZrO_2$composite was investigated by multi-pass extrusion process. To obtain sound $Al_2$$O_3$-X $O_2$sintered bodies, burning out and sintering process were carefully carried out. The sintered bodies showed continuous, fibrous monolithic microstructure without any swelling. Many microcracks were observed at the $Al_2$$O_3$-$ZrO_2$interfaces due to the mismatching of thermal expansion coefficient between $Al_2$$O_3$ and $ZrO_2$phase. Most of m- $ZrO_2$grains included twin defects such as (001), (010) and (011) type to accommodate the phase transformation induced stress.

• Elastomers and Composites
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• 제44권3호
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• pp.244-251
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• 2009

최근 들어, 자연의 기능성 표면을 모사하여 공학적으로 이용하려는 연구가 전세계적으로 급격히 증가하고 있다. 자연계에 존재하는 표면의 여러 기능을 우리 생활에 응용할 수 있다면, 현재 인류가 직면하고 있는 환경오염, 에너지고갈, 물/식량 부족 등의 문제들을 해결하는데 큰 도움이 될 뿐만 아니라, 우리가 일상생활에 사용하는 많은 제품들의 표면 기능을 고도화시킬 수 있기 때문이다. 이 글에서는 다양한 기능을 가진 자연의 표면 중 마이크로/나노구조물을 이용하여 초발수 특성을 갖는 표면에 대하여 살펴보고 초발수 표면의 이론적인 배경 및 초발수 표면을 구현하기 위한 여러 연구들에 대하여 소개하고자 한다.