• Title/Summary/Keyword: Polyvinylpyrrolidone

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Dissolution Characteristics of Hydrophobic Drug-Soluble Carrier Coprecipitates ( II ) -Dissolution Characteristics of Phenylbutazone-Polyvinylpyrrolidone Coprecipitates-

  • Park, Jae-Young
    • Journal of Pharmaceutical Investigation
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    • v.5 no.4
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    • pp.17-23
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    • 1975
  • 복용량이 비교적 적고, 난용성 의약품(醫藥品)으로 antirheumatism에 사용되고 있는 phenylbutazone을 macromolecule polymer로서 water soluble carrier인 polyvinylpyrrolidone과 solvent method로 1:1, 1:5, 및 1:9(w/w)의 coprecipitate를 형성(形成)시켰으며, 이들 coprecipitate의 용출 속도를 Pure drug 및 coprecipitate 형성 용매인methanol에서 재결정한 recrystallized pure drug의 그것과 측정 비교(比較)하였다. 1:1,1:5 및 1:9(w/w)의 coprecipitate는 recrystallized pure phenylbutazone보다 약 4.5배의 용출의 증가를 보였고, 이들 1:1,1:5,1:9(w/w)에서의 그 carrier의 양(量)에 따른 용출에의 영향은 거의 없었다. 시간(時間)에 대(對)한 log probit를 plot하여 구(求)한 dissolution half life, $T_{50%}$는 coprecipitate ratio 1:1(w/w)에서는 5.5분, 1:5에서는 10분, 1:9에서는 12.5분이었다.

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PVP-assisted Synthesis of TiO2 Nanospheres and their Application to the Preparation of Superhydrophobic Surfaces

  • Munkhbaatar, Naranchimeg;Ryu, Ilhwan;Park, Dasom;Yim, Sanggyu
    • Applied Science and Convergence Technology
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    • v.24 no.6
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    • pp.219-223
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    • 2015
  • Enhancement of the surface hydrophobicity of polydimethylsiloxane (PDMS) thin films deposited on substrates covered with titanium dioxide ($TiO_2$) nanospheres was studied. First, a low-temperature solution-phase method using polyvinylpyrrolidone (PVP) as a surface capping agent and a water/dimethylformamide (DMF) mixture as the reaction medium was used to synthesize monodisperse $TiO_2$ nanospheres. It was possible to easily control hydrolysis rate of the Ti-precursors and the size of the synthesized nanospheres by varying the amount of PVP and the volume ratio of the solvent mixture. Spray coating of the synthesized $TiO_2$ nanospheres under the PDMS film increased the water contact angle of the film surface to $150.3^{\circ}$. This simple treatment can modify the surface morphology at a nanometer scale without any long or complicated nanoprocess; hence, the surface enters the superhydrophobic Cassie-Baxter regime.

Metalloporphyrin-Catalyzed Chemoselective Oxidation of Sulfides with Polyvinylpyrrolidone-Supported Hydrogen Peroxide: Simple Catalytic System for Selective Oxidation of Sulfides to Sulfoxides

  • Zakavi, Saeed;Abasi, Azam;Pourali, Ali Reza;Talebzadeh, Sadegh
    • Bulletin of the Korean Chemical Society
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    • v.33 no.1
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    • pp.35-38
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    • 2012
  • Room temperature oxidation of organic sulfides with polyvinylpyrrolidone-supported hydrogen peroxide (PVP-$H_2O_2$) in the presence of Mn(III) complexes of meso-tetraphenylporphyrin, Mn(TPP)X (X = OCN, SCN, OAc, Cl) and imidazole (ImH) leads to the highly chemoselective (ca. 90%) oxidation of sulfides to the corresponding sulfoxide. The efficiency of reaction has been shown to be influenced by different reaction parameters such as the nature of counterion (X) and solvent as well as the molar ratio of reactants. Using Mn(TPP)OCN and ImH in 1:15 molar ratio and acetone as the solvent leads to the efficient oxidation of different sulfides.

Characterization of Phase Inversion Membrane of Sulfonated Polyetherimide (Sulfonated Polyetherimide Membrane의 특성)

  • 김완주;최남석;최중구;김인철;김종호;탁태문
    • Membrane Journal
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    • v.9 no.1
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    • pp.1-9
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    • 1999
  • Sulfonated polyetherimide having anionic charge and better hydrophilicity than polyetherimide was prepared by reacting polyetherimide with chlorosulfonic acid. To prepare casting solution, from which the membrane having good performance can produce. Polyvinylpyrrolidone as a pore forming agent and volatile weak solvent such as dichloromethane to foml the dense skin layer were added to the sulfonated polyetherimide / N -methyl-2-pyrrolidone solution. Membrane fabricated sulfonated PEl showed better fouling resistance to the protein than those fabricated PEL because of its hydrophilicity. Solute having negative charge was removed effectively with membrane fabricated from the sulfonated PEl because of its the same electron charge.

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Study of the Intraction between PVP and Silver Cation (은 양이온과 PVP의 상호작용에 대한 연구)

  • Lee, Chul-Jae;Kim, Dong-Yeub;Nam, Ki-Young
    • Journal of the Korean Chemical Society
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    • v.53 no.5
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    • pp.565-569
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    • 2009
  • The interaction between polyvinylpyrrolidone(PVP) and silver cation has been studied in water at room temperature and atmospheric pressure. The PVP and PVP/Ag composite was observed by transmission electron microscopy (TEM), UV-VIS absorption spectroscopy, Raman spectroscopy and oxygen/carbon dioxide analyzer. We identified silver cations interacting with nonbonding electrons of the oxygen atom in the carbonyl group of PVP. It was shown that PVP/Ag formed stable composites.

Preparation of Pure Silver Powders by using Mechanochemical Process (기계화학공정(機械化學工程)에 의한 은(銀)염화물로부터 고순도 은(銀)분말 제조(製造))

  • Lee, Jaer-Yeong;Tung Le, M.;Ahn, Jong-Gwan;Kim, Jong-Oh;Chung, Hun S.;Kim, Byoung-Gyu
    • Resources Recycling
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    • v.15 no.5 s.73
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    • pp.33-37
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    • 2006
  • An equal-molar mixture of silver chloride (AgCl) and copper (Cu) was ground in atmosphere conditions using a planetary ball mill to investigate mechanochemical (MC) reaction for preparation of silver powders. The reaction causes the mixture of AgCl and Cu to change the composition of the mixture, such as silver (Ag) and cuprous chloride (CuCl). Through the leaching with ammonium hydroxide solution (1 mol), CuCl can be separated from MC product, so that pure Ag powders can be obtained as the final product. Moreover, polyvinylpyrrolidone (PVP) was used as the additive not only to improve dispersion of Ag pow- der during MC process, but also to control surface oxidation of Ag powders, prepared as the final product.

Preparation and Characterization of Polyvinylpyrrolidone/${\kappa}$-Carrageenan/Hexanediol Hydrogel by Gamma-ray Irradiation (감마선을 이용한 폴리비닐피롤리돈/카파-카라기난/1,2-헥산디올 하이드로젤의 제조 및 특성)

  • Han, Il-Soo;Lim, Youn-Mook;Gwon, Hui-Jeong;Park, Jong-Seok;Nho, Young-Chang
    • Polymer(Korea)
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    • v.35 no.1
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    • pp.13-16
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    • 2011
  • In this study, the hydrogels composed of polyvinylpyrrolidone (PVP), ${\kappa}$-carrageenan (${\kappa}C$), and 1,2-hexanediol (HD) were prepared by ${\gamma}$-ray irradiation. The radiation dose was 25 kGy and the concentration of ${\kappa}C$ was 3 wt%. The physical properties of the hydrogels were investigated as a function of the concentrations of PVP and HD. The gel content and the tensile strength increased with increasing PVP concentration due to the crosslinking between the pyrrolidone molecules and decreased with increasing HD concentration. The degree of swelling was inversely proportional to the gel content because the highly crosslinked hydrogels had a tighter structure, hence reducing their water absorption. The antibacterial tests indicated that the hydrogels containing HD had antibacterial activity.

Humidity Sensor using Polyvinylpyrrolidone-Coated Mach-Zehnder Interferometer in Planar Lightwave Circuit (폴리비닐피롤리돈이 코팅된 마하젠더 간섭계 기반의 평판형 광도파로 습도센서)

  • Kim, Ju Ha;Kim, Myoung Jin;Jung, Eun Joo;Hwang, Sung Hwan;Lee, Woo Jin;Choi, Eun Seo;Rho, Byung Sup
    • Korean Journal of Optics and Photonics
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    • v.24 no.5
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    • pp.251-255
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    • 2013
  • In this paper, the characteristics of a humidity sensor implemented by Mach Zehnder Interferometer (MZI) in a Planar Lightwave Circuit (PLC) have been designed and demonstrated. The humidity outside is detected with polyvinylpyrrolidone (PVP) coated on the etched arm of the MZI. The length of the etched arm is 10 mm and the PVP was coated by dip-coating into the etched region. As the refractive index of the PVP changes with the surrounding humidity, the PVP-coated humidity sensor presented changes in the interferogram depending on RH (Relative Humidity) around the PLC. The measured results show that the proposed humidity sensor works successfully in the range of 30% to 80% of RH.

Effect of PVP(polyvinylpyrrolidone) on the Ag Nano Ink Property for Reverse Offset Printing (PVP(polyvinylpyrrolidone)가 리버스 오프셋용 은 나노 잉크 물성에 미치는 영향)

  • Han, Hyun-Suk;Kwak, Sun-Woo;Kim, Bong-Min;Lee, Taik-Min;Kim, Sang-Ho;Kim, In-Young
    • Korean Journal of Materials Research
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    • v.22 no.9
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    • pp.476-481
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    • 2012
  • Among the various roll-to-roll printing technologies such as gravure, gravure-offset, and reverse offset printing, reverse offset printing has the advantage of fine patterning, with less than 5 ${\mu}m$ line width. However, it involves complex processes, consisting of 1) the coating process, 2) the off process, 3) the patterning process, and 4) the set process of the ink. Each process demands various ink properties, including viscosity, surface tension, stickiness, and adhesion with substrate or clich$\acute{e}$; these properties are critical factors for the printing quality of fine patterning. In this study, Ag nano ink was developed for reverse offset printing and the effect of polyvinylpyrrolidone(PVP), used as a capping agent of Ag nano particles, on the printing quality was investigated. Ag nano particles with a diameter of ~60 nm were synthesized using the conventional polyol synthesis process. Ethanol and ethylene glycol monopropyl ether(EGPE) were used together as the main solvent in order to control the drying and absorption of the solvents during the printing process. The rheological behavior, especially ink adhesion and stickiness, was controlled with washing processes that have an effect on the offset process and that played a critical role in the fine patterning. The electrical and thermal behaviors were analyzed according to the content of PVP in the Ag ink. Finally, an Ag mesh pattern with a line width of 10 ${\mu}m$ was printed using reverse offset printing; this printing showed an electrical resistivity of 36 ${\mu}{\Omega}{\cdot}cm$ after sintering at $200^{\circ}C$.