• Title/Summary/Keyword: silicones

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Synthesis and Photopolymerization of Vinyl Ether and Epoxy-Functionalized Silicones

  • Pyun, Sang-Yong;Kim, Whan-Gi
    • Macromolecular Research
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    • v.11 no.3
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    • pp.202-205
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    • 2003
  • The reactive precursors, vinyl ethers, and epoxy-silicones, were synthesized. The vinyl ether monomers were prepared from primary alcohol and ethyl vinyl ether with mercury (II) acetate. The epoxy-functionalized silicones have been achieved by the controlled, rhodium-catalyzed, chemoselective hydrosilation of vinyl ether with siloxanes or silane. It was shown that the hydrosilation proceeds exclusively at the vinyl ether group of alkenyl vinyl ether without participation at the alkenyl group. The photoinduced cationic polymerization of these monomers was studied and found to be all highly reactive.

Preparation of Poly(ethylene naphthalate) Film Coated with Silicones for High Temperature Insulator (실리콘 코팅을 이용한 poly(ethylene naphthalate) 고온용 방열 필름의 제조)

  • Lee, Soo;Na, Cha-Soo
    • Journal of the Korean Applied Science and Technology
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    • v.24 no.2
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    • pp.167-173
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    • 2007
  • The surface of poly(ethylene naphthalate) film applicable to high temerature insulator for convection microwave oven was modified with silicone coating solutions in the presence of silane crosslinking agent. The structure and properties of the PEN films were investigated by using Fourier transform IR spectroscopy, viscometry, microscopy, and tensile tests. The experimental results showed that the coating with silicone enhanced thermal stability up to $200^{\circ}C$, and slightly lowered the tensile strength and elongation of the PEN films. Judging from dimensional stability results the silicone coated PEN films can not be used for higher temperature insulator above $230^{\circ}C$. Serious dimensional contraction of films was obtained during heat treatment at $250^{\circ}C$ even for 1h. However, the surface of those films still have same chemical structure of silicones. Therefore, If we use PEN film prestretched at $230^{\circ}C$ as base one it will be possible to prepare a high temperature insulator up to $230^{\circ}C$. Conclusively, a silicone coated PEN film can be suitable for the application to convection microwave oven door insulator at high temperature up to $230^{\circ}C$.

$ULTRASIL^{TM}$ ANIONIC SILICONES - Complexing Agents for Quaternary Compounds

  • B. Vondruska
    • Proceedings of the SCSK Conference
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    • 2003.09b
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    • pp.460-461
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    • 2003
  • Clear rinse-off ...gels can be prepared. allowing the introduction of novel product forms. Styling gels with improved viscosity, conditioning. clarity and product aesthetics are also possible with this concept. Beyond the creation of clear product.(omitted)

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Augmentation Mammaplasty Using Implants: A Review

  • Takayanagi, Susumu
    • Archives of Plastic Surgery
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    • v.39 no.5
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    • pp.448-451
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    • 2012
  • One of the techniques for augmentation mammaplasty is the procedure using implants. Even though this technique has been used for many years, there are still several controversial issues to be discussed and overcome for patient safety. In this review article, capsular contracture, leak or rupture of the implants, possible systemic disease, relation with breast cancer, and recent problems with Poly Implant Prothese implants are described and discussed.

The effect of Oil-aqueous phase Partition Coefficients of Phenoxyethanol according to Oils (오일이 페녹시에탄올의 유.수상 분배계수에 미치는 영향)

  • Cho, Sun-Woong;Lee, Young-Keun;Kim, Mi-Jung
    • Proceedings of the KAIS Fall Conference
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    • 2009.12a
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    • pp.390-394
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    • 2009
  • In this study, partition coefficients(Kw) of phenoxyethanol in oil-water phase according to type of oils was investigated. Partition coefficients(Kw) were experimented by classified oils that hydrocarbones, fatty alcohols, fatty acids, esters, triglycerides and silicones. It was found that partition coefficients(Kw) of hydrocarbons and silicones were low, but partition coefficients(Kw) of fatty acids, fatty alcohols, esters and triglycerides were high. It was known that the emulsions which were made of oils having low partition coefficients value had a good antimicrobial effects. Thus, the cosmetics stability of microorganisms and skin safety of phenoxyethanol could be improved by using the oils which have low partition coefficients value.

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Characteristics of Energy Dissipation in Vibration Absorbing Nano-Damper According to the Architecture of Silica Particle (세라믹 분말의 입자구조에 따른 나노 진동 흡수장치의 에너지 소산 효율 특성에 대한 연구)

  • Moon, Byung-Young;Kim, Heung-Seob
    • Korean Journal of Materials Research
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    • v.13 no.3
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    • pp.144-149
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    • 2003
  • This study shows an experimental investigation of a reversible nano colloidal damper, which is statically loaded. The porous matrix is composed from silica gel (labyrinth or central-cavity architecture), coated by organo-silicones substances, in order to achieve a hydrophobic surface. Water is considered as associated lyophobic liquid. Reversible colloidal damper static test rig and the measuring technique of the static hysteresis are described. Influence of the pore and particle diameters, particle architecture and length of the grafted molecule upon the reversible colloidal damper hysteresis is investigated, for distinctive types and mixtures of porous matrices. Variation of the reversible colloidal damper dissipated energy and efficiency with temperature, pressure, is illustrated. As a result, he proposed nano damper is effective one, which can be replaced the conventional damper.

Size Control of Silicone Particles Using Sonochemical Approaches

  • Jhung, Sung-Hwa;Yoo, Ki-Cheon;Hwang, Young-Kyu;Chang, Jong-San
    • Bulletin of the Korean Chemical Society
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    • v.28 no.12
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    • pp.2401-2404
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    • 2007
  • Particle size of silicones can be controlled by changing the reaction conditions such as temperature and concentrations of water and tetramethoxysilane (TMOS). Alternatively, the use of ultrasound radiation is also an elegant technique to decrease the particle size. Small silicone particles can be obtained at low temperature from diluted reagent containing TMOS, especially under the powerful ultrasound radiation. The size control may be explained by the rate of particle growth rather than that of nucleation.