Poly Vinyl Pyrrolidone PVP

Poly(vinyl pyrrolidone) (PVP) was introduced by the Germans in World War II as a blood plasma substitute.A water-soluble polymer, its main value is due to its ability to form loose addition compounds with many substances. 

Figure 6 (A) Non-isothermal chemiluminescence runs for oxidation of polystyrene (PS), polyethylene terephthalate) (PETP) and polyfmethyl methacrylate) (PMMA), in oxygen, heating rate 2.5°C/min. (B) Non-isothermal chemiluminescence runs for oxidation of polypropylene (PP), polyamide 6 (PA 6), poly(vinyl pyrrolidone) (PVP), polyethylene (PE) and polyamide 66 (PA 66), in oxygen, heating rate 2.5°C/min.

An illustrative example is the work of Clark et al, on the conformation of poly(vinyl pyrrolidone) (PVP) adsorbed on silica 0). These authors determined bound fractions from magnetic resonance experiments. In one instance they added acetone to an aqueous solution of PVP in order to achieve theta conditions for this polymer. They expected to observe an increase in the bound fraction on the basis of solvency effects as predicted by all modern polymer adsorption theory (2-6), but found exactly the opposite effect. Their explanation was plausible, namely that acetone, with ability to adsorb strongly on silica due to its carbonyl group, would be able to partially displace the polymer by competing for the available surface sites. 

POLY(ETHYLENE OXIDE), PEG, AND POLY(VINYL PYRROLIDONE), PVP, AS TEMPLATES... 

The most examined monomers for template polymerization have been either acrylic or methacrylic acids. This is probably because many polymers, such as poly(ethylene oxide), PEG, and poly(vinyl pyrrolidone), PVP, form complexes with poly(acrylic acid). 

Table 6.3 Effect of the amount of poly(vinyl pyrrolidone), PVP, on the polymerization of L-leucine using triphenyl phosphite in NMP. [Reprinted from N. Yamazaki and F. Higashi, Adv. Polym. Sci., 38,1 (1981)]...

For (a), hydroxypropyl cellulose (HPC) (6-8), poly(vinyl pyrrolidone) (PVP) (9,10), poly(acrylic acid) (PAA) (9), and poly(dimethyl siloxane) (PDMS) (11) are usually employed. Ober et al. reported that the copolymers of isobutylene/isoprene and various methacrylates, which have weak polarity, are appropriate stabilizers for... 

Peptide-based gene delivery, 334 Peptide nucleic acid (PNA), 73,252 Pharmacokinetics, 409 Polyethyleneimine (PEI), 369 Peptides with thiol groups, 348 Persistence of gene expression, 10,463 Physiological Pharmacokinetics, 423 PNA binding affinity, 75 Poly anion interchange, 179 Poly cations, 164 Polymeric gel, 447 Polyamidoamine (PAMAM), 376 Polyaminomethacrylates, 379 Poly(L-lysine), 336, 369 Poly(vinyl pyrrolidone) (PVP), 382 Prophylactic vaccines, 474... 

Park IK, Ihm JE, Park YH et al (2003) Galactosylated chitosan (GC)-graft-poly(vinyl pyrrolidone) (PVP) as hepatocyte-targeting DNA carrier. Preparation and physicochemical characterization of GC-graft-PVP/DNA complex (1). J Control Release 86 349-359... 

For the long-term stability of the Ag nanoparticles, surfactants have been used as protecting agents.18 Stabilizers such as sodium 2-diethylhexyl sulfosuccinate (AOT), cetyltrimethylammonium bromide (CTAB), and poly(vinyl pyrrolidone) (PVP) have been effectively employed for stabilization and also to direct the aspect ratio of the Ag nanoparticles producing different shapes such as plates, rods, discs, etc.19 All the above methods in general produce nanoparticles of Ag, but very... 

In consequent experiments, the authors (16) innovated the preparation procedure in order to improve the quality of prepared PMMA/ MWCNT particles they profitably used a steric stabilizer, poly(vinyl pyrrolidone) (PVP) (48). PVP has both hydrophobic and hydrophilic... 

The present report pursues the following goals i) to illuminate the effect of ultrasonic treatment on the crystal structure of preformed gold and platinum nanoparticles ii) to investigate the catalytic efficiency of platinum nanoparticles ultrasonically treated in ethylene glycol (EG) or poly vinyl pyrrolidone (PVP) solutions. For reproducible ultrasonic experiments a home-developed ultrasonic... 

Our bi- and tri-metallic species are derived from precursor molecules that can be denuded (chemically) to expose only the mixed-metal constituent atoms. The nanoalloys that almost all others prepare are generally formed by methods that rely on sequential addition of separate solutions such as HAuCl and PdCl [35] to form Au-Pd nanoalloys. Moreover, such nanoalloys (like the metallic nanoparticles now in extensive use [45]) are utilized in their passivated form, which means that they have surfactant species such as poly(vinyl pyrrolidone), PVP, or poly-diaUyl dimethyl ammonium chloride (PDDA) covering their surfaces (The molecular weight of which may be as large as 450 kDa). Our nanoparticles are free from such surfactants or any other stabilizing molecular entity. 

The miscibility of poly(acrylic acid) (PAA) and poly(vinyl pyrrolidone) (PVP) blends and complex was investigated by relaxation measurements. Figure 5 shows CP/MAS spectra of the PAA/PVP blends, PAA, PVP and complex. In the Ti experiment, the resonance intensities of all the samples were obtained with a series of different delay times based on the inversion... 

The deamidation rate of the hexapeptide, Val-Tyr-Pro-Asn-Gly-Ala (pH 6.8), was also characterized in poly(vinyl alcohol) (PVA) and poly(vinyl pyrrolidone) (PVP) (Lai et al., 1999a Lai et al., 1999b Lai et al., 2000 Song et al., 2001). The rate of deamidation was observed to increase with increasing water content... 

These same workers described an inverse emulsion-type polymerization process.109 They used a conventional process in which microemulsions of water in hydrocarbon readily form in the presence of Aerosol-OT(AOT). The droplets are essentially swollen cells, where radius is controlled by the water/AOT ratio. As droplets collide, hydrophilic reagents contained in them are exchanged. When pyrrole and (NH4)2S208 dispersions were mixed, eventually a sediment appeared. However, if poly(vinyl pyrrolidone) (PVP) was added at different intervals, stable dispersions of small particles could be prepared. 

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