• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.319-320
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• 2003

압전성과 초전성을 나타내는 고분자인 poly(vinylidene fluoride)(PVDF)는 poly(methyl methacrylate), poly(vinyl acetate), 및 Poly(vinyl methyl ketone)(PVMK) 등과 블렌딩하면 혼화성(miscibility)이 있다. 이들 블렌드물들을 용융온도 이상으로 승온시키면 낮은 온도에서는 균일상으로 존재하지만, 온도가 계속 증가하면 상분리되어 LCST(lower critical solution temperature)를 나타낸다[1]. 이러한 승온에 의한 상분리 거동에서 외부전장을 가하면 전기활성 고분자인 PVDF에 영향을 주어 상분리 거동이 변화될 것으로 예산된다. (중략)

• Membrane Journal
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• v.26 no.1
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• pp.62-69
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• 2016

In this study, sulfonated poly(ether ether ketone) (SPEEK) as cation exchange membrane and blended and crosslinked poly(vinyl amine) (PVAm) with poly(vinyl alcohol) (PVA) membrane as anion exchange membrane were used and then the performance experiments of the membrane capacitive deionization (MCDI) installed with both membranes were carried out. The newly prepared anion exchange membrane were characterized through water content, ion exchange capacity and FT-IR. The crosslinking time of 3 h to 5 h indicated that the salt removal was reduced from 81.3, 65.7% to 53.8%. The effect of PVAm contents from 40, 60, to 80% on the salt removal was shown 81.3, 75.2 and 37.7%, respectively. As a result, it was concluded that the crosslinking time and the content of PVAm had an influence on the salt removal efficiency.

• Bulletin of the Korean Chemical Society
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• v.33 no.10
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• pp.3171-3172
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• 2012

• Journal of the Korean Chemical Society
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• v.51 no.4
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• pp.356-360
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• 2007

5,7-Diaryl-3,4,6-trihydronaphthalen-2-ones have been synthesized from 3,5-diaryl-cyclohex-2-en-1- ones and methyl vinyl ketone in the presence of sodium ethoxide. The products were characterized by IR, UV-Visible, 1H-NMR, 13C-NMR and mass spectral techniques. To confirm 1H and 13C signals, HSQC spectrum was recorded and analyzed.

• Bulletin of the Korean Chemical Society
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• v.15 no.8
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• pp.612-614
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• 1994

• Bulletin of the Korean Chemical Society
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• v.11 no.4
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• pp.307-309
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• 1990

The stereoselectivity of the reaction between methyl vinyl ketone dimer, which contains two possible sites of chelation, and zinc borohydride or diisobutylaluminum hydride has been studied in order to illuminate the factors involved in the high levels of asymmetric induction obtained in the bicyclic system. The conditions for the formation of the exo-5,7-dimethyl-6,8-dioxabicyclo[3.2.1]octane are DIBAH reduction of MVK dimer in ether at reflux followed by acidic cyclizatioan, and for the endo isomer are $Zn(BH_4)_2$ reduction with $ZnCl_2$ at $0^{\circ}C.$.

• Journal of the Korean Chemical Society
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• v.38 no.1
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• pp.80-86
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• 1994

The synthetic pathway of ethyl $({\pm})$-8-oxo-10-oxa-l'H-spiro[1, 3]dioxolane-4,4'-tricyclo [9.2.1.0 1,6]dodec-6-ene-9-carboxylate (7), an important intermediate for the total synthesis of bruceantin analogue, was developed. Ethyl 2-cyclohexanonecarboxylate and methyl vinyl ketone were employed as starting materials. Robinson annulation, allylic oxidation, regiospecific acylation and the formation of epoxy methano bridge ring were studied. 4,4a,5,6,7,8-Hexahydro-4a-hydroxy-2(3H)naphthalenone (14) was synthesized utilizing the unusual decarboethoxylation reaction discovered during ketalization of octalone (3).

• Journal of the Korean Chemical Society
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• v.37 no.1
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• pp.141-147
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• 1993

A brief route for total synthesis of 6-deoxybisanhydrodaunomycinone(20) was described, namely the precursor of the daunomycinone, the aglycone of the anticancer antibiotic daunorubicin (1b). The prepared enone 4 was condensed with phthalide sulfone 7 to afford anthraquinone 10 after oxidation and methylation. The benzylic group of 10 was brominated, and subsequent oxidation with bis(tetrabutylammonium) dichromate followed by cyclization give hydroxyanthraquinone 16, which was displaced with thiophenol. Oxidation of 17 with m-CPBA in phosphate buffer solution afforded anthraquinonyl sulfone 18 which was condensed with methyl vinyl ketone (19) to furnish 20.

• Journal of Radiation Industry
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• v.4 no.1
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• pp.19-23
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• 2010

Vinyl ester (VE) resins, introduced in the late 1960s, have made large strides in reinforced plastics applications as adhesive and matrix materials on their appropriate mechanical performance characteristics in the glassy state. Generally, VE resins are a group of dimethacrylate resins based on bisphenol A type epoxy resin. They exhibit easy handling properties as well as good resistance to most chemical agents due to their mechanical and thermal properties. In this study, the effects of curing methods of vinyl ester resins on gel contents, flexural strength and dynamic mechanical properties were investigated. Thermal curing (room temperature, $80^{\circ}C$) and electron beam curing were used to crosslink a VE resin/styrene complex (65/35 wt%) with methyl ethyl ketone peroxide (MEKPO) as a catalyst and an 8 wt% cobalt naphthenate in styrene solution as a accelerator. For the samples, gel contents as well as flexural strength and dynamic mechanical properties were characterized and compared by soxhlet apparatus, universal testing machine (UTM) and dynamic mechanical analysis (DMA). As a result, the electron-cured VE resin was confirmed as a better condition than those for gel contents, flexural strength and dynamic mechanical properties, respectively.

• Archives of Pharmacal Research
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• v.26 no.12
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• pp.1109-1116
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• 2003

A series of 3'- and 4'-branched carbocyclic nucleosides 25, 26, 27, 28, 29 and 30 were synthesized starting from simple acyclic ketone derivatives. The construction of the required quaternary carbon was made using a [3,3]-sigmatropic rearrangement. In addition, the installation of a methyl group in the 3'-position was accomplished using a Horner-Wadsworth-Emmons (HWE) reaction with triethyl 2-phosphonopropionate. Bis-vinyl was successfully cyclized using a Grubbs' catalyst (Ⅱ). Natural bases (adenine, cytosine, uracil) were efficiently coupled with the use of a Pd(0) catalyst.