• Macromolecular Research
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• v.16 no.7
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• pp.626-630
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• 2008

Poly(vinyl pyrrolidone) was used successfully to control the size and distribution of silver nanoparticles generated on inorganic silica nanofibers. The inorganic nanofibers were electro spun using sol-gel chemistry of silicates, and the diameter of the prepared nanofibers was unaffected by adding up to 7% of poly(vinyl pyrrolidone). The silver ions, in the form of silver nitrate, were introduced into the silica nanofibers and reduced to metallic silver by ultraviolet irradiation with a subsequent thermal treatment. The size of the generated silver particles was decreased dramatically by adding poly(vinyl pyrrolidone). The size of the silver nanoparticles was 73 nm when no poly(vinyl pyrrolidone) was added but 23 nm with the addition of only 1% of poly(vinyl pyrrolidone). The extent of reduction could be checked by determining the concentration of silver ions leached into water from the silica nanofibers. After thermal treatment of the silica nanofibers, more than 99% of the silver remained in the nanofibers, indicating almost complete reduction of the silver ions to silver metal.

• Textile Coloration and Finishing
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• v.5 no.3
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• pp.182-187
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• 1993

The binding isotherms of Methylene Blue with Poly(vinyl pyrrolidone) (PVP) were determined in a Mcllvaine buffer of pH 8.0 at 3$0^{\circ}C$ by a dynamic dialysis methods. The isotherms showed a partition binding which was increase linearly with the increase of free dye concentration in solution. The Scatchard plots for Poly(vinyl pyrrolidone)-Methylene Blue gave a constant value. The results were interpreted by the McGhee and von Hippel theory considering non-cooperative binding. The intrinsic binding constant k, for Poly(vinyl pyrrolidone)-Methylene Blue was 6.02$\ell$/base mol.

• Journal of Sericultural and Entomological Science
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• v.49 no.2
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• pp.77-80
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• 2007

Silk fibroin/poly (vinyl pyrrolidone) conjugates were prepared and characterized through differential thermal calorimeter and thermogravimetry. The glass transition temperature (Tg) of poly (vinyl pyrrolidone) was not changed by reaction with silk fibroin. However, abnormal exothermic peak was observed at the silk fibroin/poly (vinyl pyrrolidone) conjugates. Thermogravimetric analysis showed that thermal stability of silk fibroin was relatively increased by reaction with PVP.

• Polymer(Korea)
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• v.36 no.3
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• pp.302-308
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• 2012

The objective of this study is to investigate optimum reaction conditions for the grafting of poly($N$-vinyl- 2-pyrrolidone) (PVP) onto the surface of plasma-treated polypropylene film. The plasma treatment conditions were fixed as 200 W rf power, 6 LPM Ar flow rate, 30 sec treatment time, and 5 min exposure time after treatment. For graft copolymerization, we investigated the change of grafting degree with respect to reaction time, reaction temperature and $N$-vinyl-2-pyrrolidone concentration. Maximum grafting degree was obtained at the conditions of 6 h reaction time, $90^{\circ}C$ reaction temperature, and 40% $N$-vinyl-2-pyrrolidone concentration. The introduction of PVP was confirmed by ATR-FTIR, XPS, and SEM analysis.

• Bulletin of the Korean Chemical Society
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• v.31 no.7
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• pp.1869-1874
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• 2010

By reducing PVP with $H_2NOH$.HCl and NaOH 2:2:1 mass ratios in aqueous ethanol, poly-N-vinyl pyrrolidone oxime [PVPO] was prepared with 92% yield. Applying the sol-gel concept, orthosilicic acid [OSA] was made by hydrolyzing TEOS with ethanol in 1:0.5 molar ratios using 1 N KOH aqueous solution as a catalyst. The OSA + PVPO + $_L$-Valine ($\alpha$-amino acid) were mixed with pure ethanolic medium in 1:2:2 mass ratios and refluxed at $78^{\circ}C$ and 6 pH for 6.5 h. A white residue of poly-N-vinyl pyrrolidone oximo-L-valyl-siliconate [POVS] appeared after 5 h. The heating of reaction mixture was stopped and the contents were brought to NTP. The residue formation of POVS was intensified with lowering a temperature and completely solidified within 5 h, was filtered using a vacuum pump with Whatmann filter paper no. 42. The residue of POVS was washed several times with 20% aqueous cold ethanolic solution and dried in vacuum chamber at $25^{\circ}C$ for 24 h. The MP was noted above $350^{\circ}C$. Structural and internal morphology were analyzed with IR and $^1H$-NMR, and SEM respectively. A drug loading and transporting ability of the POVS in water and at pH = 5 and 8 was determined chromatographically.

• Clean Technology
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• v.14 no.4
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• pp.242-247
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• 2008

Poly(N-vinyl-2-pyrrolidone) (PVP) has been used as biocompatible and biodegradable polymer in cosmetics, pharmaceuticals and electronics. Micro-particles of PVP were produced using an aerosol solvent extraction system (ASES). Dichloromethane (DCM) and supercritical carbon dioxide were used as solvent and antisolvent, respectively. The mean diameter of the obtained polymer particles ranged from 0.184 to $0.249\;{\mu}m$. The relationship between particle size and initial drop size was also considered.

• Bulletin of the Korean Chemical Society
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• v.30 no.4
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• pp.972-974
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• 2009

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2584-2592
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• 2011

Nickel nanoparticle-poly(N-vinyl-2-pyrrolidone)/$TiO_2-ZrO_2$ composite (Ni-PVP/$TiO_2-ZrO_2$) was prepared by in situ polymerization method. The physical and chemical properties of Ni-PVP/$TiO_2-ZrO_2$ were investigated by XRD, FT-IR, BET, TGA, SEM and TEM techniques. The catalytic performance of this novel heterogeneous catalyst was determined for the Suzuki-Miyaura cross-coupling reaction between aryl halides and phenylboronic acid in the presence of methanol-water mixture as solvent. The effects of reaction temperature, the amount of catalyst, amount of support, solvent, and amount of metal for the synthesis of Ni-PVP/$TiO_2-ZrO_2$, were investigated as well as recyclability of the heterogeneous composite. The catalyst used for this synthetically useful transformation showed considerable level of reusability besides very good activity.

• Archives of Pharmacal Research
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• v.27 no.12
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• pp.1284-1289
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• 2004

Galactosylated chitosan-graft-poly(vinyl pyrrolidone) (GCPVP) was synthesized and characterized for hepatocyte-targeting gene carrier. GCPVP itself as well as GCPVP/DNA complex had negligible cytotoxicity regardless of the concentration of GCPVP and the charge ratio, but GCPVP/DNA complex had slightly cytotoxic effect on HepG2 cells only in the case of the higher charge ratio and 20 mM of $Ca^{2+}$ concentration used. Through the confocal laser scanning microscopy, it is shown that the endocytosis by interaction between galactose ligands of GCPVP and ASGPR of the hepatocytes was the major route of transfection of GCPVP/F-plasmid complexes.

• Applied Chemistry for Engineering
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• v.26 no.4
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• pp.458-462
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• 2015

It is essential to employ a binder to prepare transparent films from conductive polymer such as poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) (PEDOT/PSS). In this paper, poly(vinyl alcohol) (PVA), poly(vinyl pyrrolidone) (PVP), and PSS were selected as a binder, and their effects were investigated. The formation of the film was found to be primarily dependent on the surface tension of coating solution including PEDOT/PSS and a binder. When PSS was used as a binder, the film was not formed. In case of using PVP, it was easily peeled off from the substrate. However, when using the PVA or the mixtures of PVA and PSS or PVA and PVP as a binder, films with good transparency and uniform surface resistances were produced. Based on adhesion and long-term stability tests, we concluded that the mixture of PVA and PSS is the best binder for preparing antistatic films of PEDOT/PSS.