• Title/Summary/Keyword: Polymer Material

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Mechanical Strength Properties of Hanger Insulator for Arrestor (피뢰기 절연행거의 기계적 강도 특성)

  • 박기호;조한구;한동희
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.589-592
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    • 2001
  • Generally, hanger insulator for polymer arrestor have to be good insulation properties and mechanical strength and weatherability, But many remark and repairs have been to think about low cost and light weight. The Paper is used Polymer arrestor for post and performance analysis and mechanical strength insulator hanger according to development of simplest product. To enhance the efficiency of experimental modal analysis, we proposed the process which is the selection of the locations and the number of measurement points for pre-test.

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Development of Polymer Crossarms (폴리머 절연완철 개발)

  • 조호령;이철호;조영신;김상욱
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.307-310
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    • 2001
  • This paper reports the developing and manufacturing process of polymeric crossarms in place of conventional crossarms made of steel used for overhead lines. The use of insulated crossarms has been mandatory in order to achieve the required line compaction in the pole. The developed polymer crossarm is characterised by significantly less weight, easier handling, much longer insulation length which leading to reduce the flashover outage from bird nest.

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Smouldering Combustion of Combustible Natural Polymer Dust Layer (가연성 천연고분자 분체의 훈소에 관한 연구)

  • Kim, Hong
    • Journal of the Korean Society of Safety
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    • v.5 no.1
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    • pp.7-18
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    • 1990
  • This study measured the smouldering temperature of dust layer for various combustible natural polymer material by practical apparatus. The dust layer was either put on the preheated plate of constant temperature, or formed with cylinderical metal sleeve of various diameters and depths at room temperature and then heated up to a pre-determined smouldering temperature. Plots of arrival times versus smouldering temperature were made to compare the smouldering characteristics with kinds of dusts. The natural polymer material was divided into theree groups by characteristics of smouldering mechanism. This groups are cellulose group, lipide group and glucose group.

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Effect of the Molecular Structure of Rubbed Polyimide Films for Surface Liquid Crystal Alignment of Nematic Liquid Crystal (네마틱 백정의 표면 액정 배향에관한 폴리이미드막의 분자 구조의 효과)

  • 서대식
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1996.05a
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    • pp.232-234
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    • 1996
  • We have investigated the effect of molecular structure of polymer of rubbed polyimide (PI) films for surface liquid crystal alignment. To obtain surface alignment effect of Polymer molecular structure, we measured the polar (out of plane-tilt) anchoring strength and surface ordering of 5CB on rubbed PI surfaces. We have found that the polar anchoring strength of 5CB is depend on the polymer molecular structure of these unidirectionally rubbed PI surfaces.

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Experimental and Numerical Study on Anisotropic Phase Separation of Liquid Crystal and Polymer Composites Cell Gap Variation

  • Jin, Min-Young;Bae, Ji-Hong;Kim, Jae-Hoon
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08a
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    • pp.567-570
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    • 2007
  • Cell gap dependence on anisotropic phase separation was studied. The results showed that the morphology of phase separation depended on cell gap and material parameters. With numerical simulation and experiments, the optimal range of cell gap in the formation of polymer layer and liquid crystal was suggested for given material parameters.

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Electrical Characteristics of Polymer Insulators with Field Aging (현장열화에 따른 폴리미애자의 전기적 특성)

  • 한재홍;이병성;김찬영;한용희
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.05a
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    • pp.522-525
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    • 1999
  • The electrical characteristics of 3 year field-aged polymer insulators which dismounted from five regions were investigated. There was a little difference in PD inception voltage depending on the manufacturers and the regions. The results between PD and SD showed a close relation. There were no significant changes in electrical properties. So, it can be considered that the field-aged insulators are sound for the present.

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Dielectric and Piezoelectric Properties of PZT/polymer Composites toes for Ultrasonic Transducer Applications (초음파 변환기용 PZT/고분자 복합 압전체의 유전 및 압전 특성)

  • 박정학;최헌일;사공건
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1994.05a
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    • pp.13-16
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    • 1994
  • The porous PZT was prepared from a mixture of PZT and polyvinylalcohol (PVA ) powders by BURPS( Burnedout Plastic Sphere) technique. The dielectric and piezoelectric properties of piezoceramic/polymer composites dependent on the PVA wt. % were evaluated. The density of PZT/polymer 3-3 composites were decreased almost linearly with increasing the PVA wt. %.

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The Material Characteristics of Steel Fiber Reinforced Polymer Concrete (강섬유 보강 폴리머 콘크리트의 재료적 특성)

  • 김기락
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.41 no.3
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    • pp.73-80
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    • 1999
  • The objective of this study were to investigate the properties and to improve the disadvantages of the polymer concrete such as brittle fracture, large hardening shrinkage . In this paper, steel fiber reinforced polymer concrete is prepared with various steel fiber aspect ratios(ι/d), contents(vol.%), and their material characteristics were investigated experimentally . The aspect ration (ι/d) of the steel fiber was reversly proportional to slump value, and slump value tended to decrease as increase of steel fiber content . And harding shrinkage and impact resistance tended to be improved as the steel fiber content and aspect ration were increased.

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STUDY PROCESSES OF INTUMESCENCE IN FIRE-PROTECTING COATINGS

  • Efremov, V.L.;Paltseva, N.G.;Leiman, Z.A.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.657-658
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    • 2005
  • Flame retard of polymers was studied for prevention from burning by various additives stimulated the char formation during heating and thermal degradation of polymer materials. Forming char have high porosity, low thermal conductivity and act as thermal shield for heat transmission from the flame to the polymer and. oxygen towards the polymer. The results showed that various additives may regulate the processes of intumecsence. The efficient fire protective intumescent char was result of processes of melting, gas evolution, cross-linking, carbonization etc.

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