• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제50권10호
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• pp.479-488
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• 2001

The effects of accelerated Ultraviolet (UV) radiation on High temperature vulcanized (HTV), Room temperature vulcanized (RTV) silicone rubber and two types of ethylene propylene diene terpolymer (EPDM) used for composite insulator were inverstigated by hydrophobicity class (HC), surface voltage decay after corona charging, SEM-EDS, FTIR and XPS. The contact angle in two kinds of silicone rubber was scarcely change, but EPDM occurred to the loss of hydrophobicity followed by surface cracking and chalking. The surface voltage decay on UV-treated silicone rubber and EPDM showed a different decay trend with UV treatment. EDS and XPS analysis indicated that the oxygen content increased with UV treatment time in all samples. For silicone rubber, the oxidized groups of inorganic silica-like structure increased with UV treatment time. The oxidized carbon of C=0, O=C-O in EPDM increased. These oxidized surface for each material had different electrostatic characteristics, so deposited charges were expected to have different impacts on their surface hydrophobicity. The degradation mechanism based on our results was discussed.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제50권10호
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• pp.494-499
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• 2001

The effects of accelerated Ultraviolet (UV) radiation on High temperature vulcanized (HTV), Room temperature vulcanized (RTV) silicone rubber and two types of ethylene propylene diene terpolymer (EPDM) used for composite insulator were investigated by hydrophobicity class (HC), surface voltage decay after corona charging, SEM-ES, FTIR and XPS. The contact angle in two kinds of silicone rubber was scarcely change, but EPDM occurred to the loss of hydrophobicity followed by surface cracking and chalking. The surface voltage decay on UV-treated silicone rubber and EPDM showed a different decay trend with UV treatment. EDS and XPS analysis indicated that the oxygen content increased with UV treatment time in all samples. For silicone rubber, the oxidized groups of inorganic silica-like structure increased with UV treatment time. The oxidized carbon of C=O, O=C-O in EPDM increased. These oxidized surface for each material had different electrostatic characteristics, so deposited charges were expected to have different impacts on their surface hydrophobicity. The degradation mechanism based on our results was discussed.

• 대한화학회지
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• 제48권3호
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• pp.266-272
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• 2004

소형 고체상 전극에 단일 조성 실온 경화형(one-component room temperature vulcanizing type) 실리콘러버 730(730 RTV)을 지지체로 도입하여 가소제가 필요 없는 탄산이온선택성 전극막을 개발하였다. 본 연구에서 최적화된 탄산이온선택성 전극막의 조성은 85.75 wt%의 730 RTV, 11.08 wt%의 trifluoroacetyl-p-decylbenzene(TFADB), 3.17 wt%의 tridodecyl-methylammonium chloride(TDMACl)로 제조 되었고, 우수한 전기화학적 특성(감응기울기 (26.3 mV/dec.), 선택성($logKT^{pot}_{CO_{2},Cl^-}$= -4.00, $logKT^{pot}_{TCO_{2},Sal^-}$=1.69), 검출한계(4.0${\times}10^{-4}M$))을 보였으며, 이와 같은 조성의 막을 도입한 평면형 고체상 센서는 60일 이상 초기특성을 유지하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.29-29
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• 2010

Engineering plastics have excellent electrical properties, mechanical strength and various characteristic which include chemical resistance, environmental resistance, weatherability at a wide temperature range. It has good characteristic(light weight, good productivity) as compare with epoxy or porcelain insulators. However, engineering plastics not suited to outdoor insulator because it isn't hydrophobic. Therefore, to over come these critical problems, we improve the surface insulation characteristics of engineering plastic by coating micro-, nano- size inorganic fillers added to RTV-SIR(Room temperature vulcanized-silicone rubber) at this plastic surface. The effect is analyzed through salt-fog test, tracking test. In conclusion, the engineering plastic coated RTV with micro-$Al_2O_3$20[phr], nano-Al(OH)3 1 ~ 3[phr] improved much better than the others.

• Transactions on Electrical and Electronic Materials
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• 제18권5호
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• pp.246-249
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• 2017

Pollution flashover of outdoor insulators is a common risk, which affects the safe operation of overhead transmission networks. Early electrical power systems, which feature insulators made from ceramic materials have been used all over the world with good performance. At present, non-ceramic insulators are in common use, as a result of their good electrical as well as mechanical properties. The aim of this paper is to discuss and compare the flashover performance of insulators typically used in power lines, such as, porcelain, ethylene-propylene-diene-monomer (EPDM) rubber, room temperature vulcanized (RTV) and high temperature vulcanized (HTV) coated silicone rubber. The effect of various parameters, including the severity of pollution, ice accumulation, and shade profile, are considered.. From the studies reviewed it was concluded that there is a distinct difference in the flashover voltages of different types of insulators, and the silicone provides the best flashover performance of all insulating materials.

• Journal of Electrical Engineering and Technology
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• 제10권3호
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• pp.1181-1187
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• 2015

Sulfur hexafluoride (SF₆) gas is used widely in electric power equipment such as Gas Insulated Switchgear (GIS), Gas Insulation transmission Line (GIL), and Gas Circuit Breaker (GCB). But applications of SF₆ should be restricted because SF6 gas is one of the greenhouse effect gases. To reduce use of SF₆ gas, a study on eco-friendly alternative insulation medium is needed. In this paper, we investigated lightning impulse (LI) breakdown of dry-air which is attracting attention as an ecofriendly alternative gas and the LI breakdown of hybrid insulation combined with dry-air and solid insulation (Room-Temperature Vulcanizing Silicone Rubber-RTV SIR) and dry-air in inhomogeneous fields according to gap distance and pressure. The experiment results showed that the LI breakdown strength of hybrid insulation system was higher than that of dry-air insulation system. It was verified that the development of technology related to eco-friendly power apparatus compact such GIS, GCB and GIL can be used as basic research data.

• 대한기계학회논문집A
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• 제37권12호
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• pp.1465-1471
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• 2013

다중벽 탄소나노튜브 (CNT), 카본블랙 (CB) 그리고 희석제의 함유량에 따른 상온경화형 실리콘 고무복합재료의 전기적 및 기계적 특성에 대해 연구하였다. 기지 내에 CNT 및 CB의 분산을 향상시키기 위해서 희석제를 사용하였다. CNT 강화 복합재료의 전기적 및 기계적 특성은 같은 함유량의 CB이 강화된 복합재료에 비해 향상되었다. 희석제의 함유량이 80phr일 때, 복합재료의 전기저항은 CNT 함유량 증가에 따라 크게 감소하였고, CNT 2.5phr에서 접촉점 포화현상을 보였다. 희석제 함유량 증가에 따라 전도성 입자들의 분산은 향상되었지만, CB의 무게비 감소로 임계 CB 함유량은 증가하였다. 희석제의 함유량 증가로 많은 CNT와 CB의 혼합이 가능하므로 유연하면서 전기적 특성이 우수한 전극의 제작이 가능하다고 판단된다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전기물성,응용부문
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• pp.123-127
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• 2003

액상실리콘으로 이루어진 초고압전력케이블용 프리몰드 접속재의 반도전-절연체 계면접합체를 다양한 제조조건과 조합별로 제조하여 계면접착력에 대한 영향을 검토하였다. 후가교적용 시 계면접착력이 강화되며 grade조합에 따른 특성차이가 존재하였다. 하지만 고온 장시간의 후가교 조건에서는 계면간의 화학적 결합력의 저하로 인해 오히려 접착력이 낮아지기도 하였다. 절연 RTV와의 계면접착성은 S-1재료가, 절연 LSR의 경우에는 S-3 재료가 가장 우수하였으며 도전안정성 측면에서도 S-3 재료가 상대적으로 유리하였다. 매입형 전극체를 제조하여 절연파괴거동을 연구한 결과 계면접착성과의 직접적인 상관관계는 크지 않음을 알 수 있었다.

• 대한기계학회논문집A
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• 제33권5호
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• pp.489-495
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• 2009

A novel technique to measuret of viscoelastic properties of polymers is proposed to investigate complex Poisson's ratio as a function of frequency. The forced vibration responses for the samples under the normal and the shear deformation are to be measured with varying load masses. The measured data were used to obtain the viscoelastic properties of the material based on an accurate 2D numerical deformation model of the sample. The 2D model enabled us to exclude data correction by the empirical form factor used in 1D model. Comprehensive measurements of viscoelastic properties of two slightly varied silicone RTV rubber ($Silastic^{(R)}$ S2) compositions were performed. Standard composition (90% PDMS polymer + 10% catalyst) and modified composition (92.5% polymer + 7.5% catalyst) were tested in temperature range from $30^{\circ}C$ to $70^{\circ}C$. Shear modulus, modulus of elasticity, loss factor, and both the real and the imaginary parts of the Poisson's ratio were determined for frequencies from 50 to 400Hz in the linear deformation regime (at relative deformations $10^{-4}{\sim}10^{-3}$).

• 한국응용과학기술학회지
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• 제30권2호
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• pp.258-263
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• 2013

Carbazole, EDOT 와 benzobisthiazole이 포함되어진 새로운 전도성 고분자의 합성 및 특징을 유기 분광학적인 방법으로 규명하였다. 포텐티오메트릭 이온 선택성 막 전극들은 넒은 감응범위($10^4{\sim}10^7$)와, 시료의 혼탁도에 영향을 주지 않으며, 빠른 감응 시간과 소형화가 쉬운 이유로 병원, 환경과 산업 현장에서 널리 이용되고 있다. 이 전극의 막에는 강한 흡착과 열적인 안정성에서 뛰어난 상온에서 경화시킨 (RTV)-타입 실리콘 고무가 사용되었다. 불행하게도, 이 실리콘 고무 기반의 전극의 높은 막 저항(PVC 기반의 것과 비교하여 $10^2{\sim}10^3$배 더 높은 수치)이 응용에 제한이 되어 왔다. 여기에서 우리는 실리콘 고무 막에 전도성 고분자를 첨가 하여 막 저항이 줄어든 새로운 고체 전극을 구현하였다.