• Title/Summary/Keyword: Olefin

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Explorations of the Heteroatom Directed Photoarylation Reaction. A Review of the Photoinitiated Intramolecular Cycloaddition Reactions of Ylide Systems

  • Dittami, James P.
    • Journal of Photoscience
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    • v.10 no.1
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    • pp.21-35
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    • 2003
  • The photoinitiated intramolecular ylide-olefin addition has been developed as an approach for the construction of one ring and two chiral centers, two rings and three chiral centers or three rings and six chiral centers in a single experimental operation from relatively simple starting materials. These investigations have uncovered several interesting and unusual reactions, which are sensitive to controls such as wavelength, temperature and solvent.

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Synlube 제조에 관한 연구(I)

  • 김종호
    • Tribology and Lubricants
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    • v.5 no.2
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    • pp.7-20
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    • 1989
  • 합성윤활유(synthetic lubricant)라 함은 현재까지도 계속되고 있는 광유(mineral oil) 전성시대의 광유에 대응되는 말로써 광유계 윤활유로 부터 얻기 어려운 높은 점도지수, 우수한 저온 유동성 등의 특성을 얻기 위해 유기합성방법에 의해 인위적으로 제조한 윤활유의 총칭이며 작용기의 종류, 합성방법, 등에 따라 다양하게 분류된다. 합성윤활유의 종류에는 합성방법에 따라 폴리머형(P형), 비폴리머형(N형)으로 대별되는데, 폴리머형 합성유에는 poly-butene, poly-$\alpha$-olefin, Polyalky lenglycol, Silicon oil, Chlorofluorocarbon, Perfiuoroalkylpolyether 등이 있으며, 비폴리머형 합성유에는 Alkylbenzene, Dibasicacidester, Polyolester, Silicate-ester Polyphenylether, Complex ester 등이 포함된다. 전자의 경우에는 중합반응 조건을 조절하므로써 여러점도 등급의 합성유들을 얻을 수 있는 반면 후자의 경우에는 분자량이 크지 않으므로 저점도의 것만 얻어지는 것이 특징이다.

High Performance Phenoxytitanium-Based Catalysts for Olefin Polymerization

  • Miyatake, Tatsuya
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.159-160
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    • 2006
  • We developed novel catalyst, PHENICS composed of the combination of a cyclopentadienyl group to perform a high catalytic activity and a bulky phenoxy group, which performs the production of high molecular weight polyolefin. The polymerization activity of PHENICS at high temperature is higher than well-known CGC catalyst. PHENICS showed the excellent ability of comonomer incorporation into polymer chain. The obtained copolymer had a high molecular weight. The PHENICS catalyst is also active to the copolymerization of ethylene and several vinyl comonomers such as styrene, norbornen, and conjugated dienes. We will discuss new cocatalysts for PHENICS to improve activity and the ability of molecular weight control.

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Construction of Ortho-Phenylene-Bridged Cp/Amido Titanium Complexes and Their Ethylene/Apha-Olefin Copolymerizations

  • Cho, Dae-Joon;Wu, Chun-Ji;Lee, Bun-Yeoul
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.223-223
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    • 2006
  • A Suzuki-coupling route is developed for preparation of ortho-phenylene-bridged Cp/amido complexes, one of which shows higher activity, higher 1-hexene incorporation, and higher molecular weight than the silylene-bridged standard CGC $[Me_{2}Si({\eta}^{5}-Me_{4}Cp)(N^{t}Bu)]TiCl_{2}$.

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Preparation of High Transparent Olefin Copolymer with Metallocene Catalyst

  • Lee, Dong-Ho;Choi, Yeon-Seok;Ha, Ki-Ryong
    • 한국정보디스플레이학회:학술대회논문집
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    • 2003.07a
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    • pp.1028-1029
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    • 2003
  • The copolymerization of ethylene and norbornene was carried out with ansa-metallocene and modified methylaluminoxane (MMAO) cocatalyst. The copolymerization behavior was changed with the structure of metallocene catalysts. In addition the catalyst activity was dependent on the structure of MMAO, i.e.. MMAO-4 which contains less i-butyl group compared to MMAO-3A exhibited higher catalyst activity than MMAO-3A. The glass transition temperature and the composition of the produced copolymer were not affected by MMAO type.

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