• Title/Summary/Keyword: Acetophenone

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The Improvement of Thermal Stability and Tensile Toughness by the Photocrosslinking of Poly(phenylene sulfide) containing Acetophenone (아세토페논을 함유한 Poly(phenylene sulfide)의 광가교에 의한 내열성과 인장인성 강화)

  • Jang, Yong-Joon;Jang, Jinho
    • Textile Coloration and Finishing
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    • v.24 no.4
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    • pp.281-287
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    • 2012
  • Poly(phenylene sulfide) films containing acetophenone as a photoinitiator were photocrosslinked under UV irradiation using a continuous UV irradiator. The gel fraction of the irradiated PPS in 1-Chloro naphthalene reached 94.7% with increasing UV energy and the photoinitiator concentration in the film upto $200J/cm^2$ and 12wt% respectively. Solid state $^1C$ NMR analysis suggested that the crosslinking occurred between the phenylene chains in PPS, indicating that the acetophenone may the phenylene hydrogens and subsequently adjacent polymer radicals could be recombined to form the crosslinked structure. The crosslinking improved the thermal behavior of PPS such as loss of $T_g$ and $T_c$, higher melting point and lower melting enthalphy as well as significantly higher peak pyrolysis temperature as much as $63.5^{\circ}C$. Surprisingly the tensile toughness of the most crosslinked PPS increased by 842%, resulting from the substantial enhancements in tensile modulus, strength and strain as much as 76%, 236% and 240% respectively. Also dynamic mechanical measurement indicated that the distance between crosslinks in the crosslinked PPS reached 85.3 g/mol corresponing to a crosslink density of 0.012 mol/g.

Indole Derivatives I, The Kinetics and Mechanism of the Nucleopilic Addition of Thiourea to 1-Benzylindole-3-Acetophenone (인돌유도체 I, 1-Benzylindole-3-acetophenone유도체에 대한 Thiourea의 친핵성 첨가반응 메카니즘과 그 반응속도론적 연구)

  • Lee, Ki-Chang;Hwang, Sung-Kwu;Ryu, Jung-Wook;Hwang, Young-Hyun;Sung, Ki-Chun
    • Journal of the Korean Applied Science and Technology
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    • v.8 no.2
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    • pp.175-181
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    • 1991
  • The kinetics of the addition of 1-benzylindole-3-(p-substituted) acetophenone derivatives was investigated by ultraviolet spectrophotometery in 30% dioxane -$H_2O\;at\;25^{\circ}C$. A rate equation which can be applied over wide pH range was obtained. The Substituent effects on 1-benzylindole-3-(p-substituted) acetophenone derivatives were studied, and addition were facilitated by electron attracting groups. On the base of the rate equation, substituent effect, and general base effect the plausible addition mechanism was proposed : Below pH 3.0, only neutral thiourea molecule was added to the carbon-carbon double bond, and in the range of pH 0.0${\sim}$14.0, netural thiourea molecule and thiourea anion competitively attacted the double bond. By contrast, above pH 10.0, the reaction was dependent upon only the addition of thiourea anion.

A Direct Comparison Study of Asymmetric Borane Reduction of C=N Double Bond Mediated by Chiral Oxazaborolidines

  • Cho Byung Tae;Ryu, Mi Hae;Chun Yu Sung;Dauelsberg Ch.;Wallbaum Sabine;Martens Jurgen
    • Bulletin of the Korean Chemical Society
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    • v.15 no.1
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    • pp.53-57
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    • 1994
  • A comparison study on asymmetric borane reduction of ketoxime ethers and N-substituted ketimines possesing C = N double bond mediated by the selected chiral oxazaborolidines (1-6) was investigated. Thus, an aromatic ketoxime O-alkyl ether acetophenone oxime O-methyl ether was reduced to the corresponding amine (1-phenylethylamine 8a) with optical yields, such as 58% ee with 1, 86% ee with 2, 3% ee with 3, 99% ee with 4, 60% ee with 5, and 73% ee with 6. However, the reduction of an aliphatic ketoxime derivative 2-heptanone oxime O-methyl ether provided low optical inductions (7-13% ee). For ketoxime O-trimethylsilyl ethers, the reduction of acetophenone O-trimethylsilyl ether afforded 8a with optical yields which were 90% ee with 1, 40% ee with 2, 2% ee with 3, 62% ee with 4, 5% ee with 5, and 60% ee with 6. The reduction of 2-heptanone O-trimethylsilyl ether also gave the product amine with low optical yields (10-40% ee). In the case of N-substituted ketimines, the reduction of acetophenone N-phenylimine afforded the corresponding amine with 79% ee, 78% ee, 9% ee, 73% ee, 78% ee and 67% ee using 1, 2, 3, 4, 5, and 6, respectively, whereas low optical inductions (5-18% ee) for 2-heptanone N-phenylimine were achieved.

Total Synthesis of a Norneolignan from Ratanhia Radix

  • Choi, Hong-Daei;Seo, Pil-Ja;Son, Byeng-Wha
    • Archives of Pharmacal Research
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    • v.25 no.6
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    • pp.786-789
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    • 2002
  • The total synthesis of a norneolignan isolated from Ratanhia, 5-(3-hydroxypropyl)-2-(2'-methoxy-4'-hydroxyphenyl)benzofuran (8), is described. The key steps contain the one-pot reaction for a 2-arylbenzofuran 6 from methyl 3-(4-hydroxyphenyl)propionate with 2-chloro-2-methylthio-(2'-methoxy-4'-acetoxy)acetophenone (5) in the presence of $ZnCl_2$, and reductive desulfurization of the resulting product 6.

The dyeability of m-Aramid Fabrics with Basic Dye Using Supercritical $CO_2$ ($CO_2$ 초임계 염색법을 적용한 메타 아라미드 직물의 basic dye에 대한 염색성)

  • Lim, Jin-Suk;Shim, Jae-Jin;Kim, Sam-Soo
    • Proceedings of the Korean Society of Dyers and Finishers Conference
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    • 2011.03a
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    • pp.57-57
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    • 2011
  • 본 실험에서는 메타 아라미드 섬유의 basic dye에 대한 염색성 특히, 물과 acetophenone을 적용한 수계 염색과 친환경 염색 매개체인 이산화탄소 초임계유체를 사용한 염색을 수행한 후에 염색된 시료에 대한 염색성을 평가하였다. 수계염색의 경우, co-solvent carrier로 acetophenone 사용하였으며, 초임계유체 염색에서는 ethanol을 co-solvent로 사용하였다. 염색된 시료의 염색성 평가는 색차계를 사용하여 실시하였으며, 최대흡수파장에서 표면반사율에 따른 Kubelka-Munk식을 적용하여 K/S값을 계산하였다. 수계 및 초임계 염색에 의해 염색된 시료가 동일한 K/S 값을 가지기 위해서는 초임계염색이 상대적으로 높은 농도의 염료가 요구되어졌다. 또한 UV-vis. 분광분석법과 광학현미경을 통한 염색시료의 염색성의 평가가 이루어졌다.

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A study on the Carrier Dyeing for PET Fiber (PET 섬유의 캐리어 염색에 관한 연구)

  • Song, Kyoung-Hun;Lee, Mun-Soo;Lee, Rae-Yohon
    • The Journal of Natural Sciences
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    • v.9 no.1
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    • pp.169-175
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    • 1997
  • In this study, it was investigated about dyeability, light-fastness, wash-fastness and tensile strength in PET fiber using the effective carrier solvent such as benzyl alcohol, benzaldehyde and acetophenone. As a results, dyeability in mixed solvent was better than that of single solvent. And dyeability in mixed solvents of benzyl aldehyde and acetophenone was of them. But effective carrier action was resulted in decrease of properties such as light-fastness and tensile strength of PET fiber after dyeing.

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Analysis of Volatile Flavor Constituents in Green Tea Flower (녹차나무꽃의 향기성분 분석)

  • Baik, Soon Ok;Bock, Jin Young;Han, Sang Bin;Cho, Kyung Suk;Bang, Guk PiI;Kim, Il Kwang
    • Analytical Science and Technology
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    • v.9 no.4
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    • pp.331-335
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    • 1996
  • Flavor constituents of green tea flower produced in Korea were analyzed by gas chromatography and mass spectrometry. 56 compounds in sample were separated and indentified as 22 hydrocarbons, 14 alcohols, 6 aldehydes, 5 esters, and 9 others. Higher concentrated substances were heneicosyl formate, ${\alpha}$-phenyl ethyl alcohol, and acetophenone. Germacrene D as a sesquiterpene were also identified.

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Total Synthesis of a Demethoxy-egonol from Styrax obassia

  • Choi, Hong-Dae;Ha, Mun-Choun;Seo, Pil-Ja;Son, Byeng-Wha;Song, Jin-Cherl
    • Archives of Pharmacal Research
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    • v.23 no.5
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    • pp.438-440
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    • 2000
  • The total synthesis of a demethoxy-egonol isolated from Styrax obassia, 5-(3-hydroxypropyl)-2-(3',4'-methylenedioxyphenyl)benzofuran (9), is described. The key steps involve the construction of a 2-arylbenzofuran skeleton 7 from methyl 3-(4-hydroxyphenyl)propionate with 2-chloro-2-methylthio-(3',4'-methylenedioxy) acetophenone (6) in the presence of ZnCl$_2$ and successive desulfurization of the resulting product 7.

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Synthesis of Photobase Generators and Their Use for Design of Polymeric Photosensitive System

  • Tsunooka, Masahiro;Tachi, Hideki;Asakino, Kaori;Suyama, Kanji
    • Journal of Photoscience
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    • v.6 no.3
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    • pp.145-151
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    • 1999
  • The use of O-carbamoyloximes as photobase generators was investigated. $\alpha$-Meth-ylbenzilydeneamino phenylcarbamate(2a) and $\alpha$-methyl benzilydeneamino cyclohexylcarbamate(2b) were prepared by the reaction of phenyl or cyclohexyl isocyanates with acetophenone oxime , respectively. Aniline, phenylhydrazine and N, N'-diphenylhydrazine were detected in thephotolysis of 2a and cyclohexylamine and cyclohexylhydrazine in the photolysis of 2b. A monomer having pendant carbamoyloxyimino groups (BGM) was prepared by the reaction fo methancryloyloxyethyl iocyanate with acetophenone oxime, and copolymerized with styrene. The BGM copolymer films turned insoluble on UV irradiation, and the degree of insolubilizationwas increased by post-baking. The photocrosslinking was thought to be due to coupling of resulting pendant aminyl radicals, and the thermal crosslinking was due to association of resulting amino and hydrazino groups by hydrogen bonding. The introduction of epoxy groups into polymer increased the degree of thermal crosslinking by post-baking.

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