V-Vinyl-2-pyrrolidone

We first prepared gold clusters stabilized by conventional water-soluble pol5mer, FVF (FVF = poly(V-vinyl-2-pyrrolidone), M = 40kDa) [21]. 

An alcohol reduction method has been applied to the synthesis of polymer-stabilized bimetallic nanoparticles. They have been prepared by simultaneous reduction of the two corresponding metal ions with refluxing alcohol. For example, colloidal dispersions of Pd/Pt bimetallic nanoparticles can be prepared by refluxing the alcohol-water (1 1 v/v) mixed solution of palladium(II) chloride and hexachloro-platinic(IV) acid in the presence of poly(/V-vinyl-2-pyrrolidone) (PVP) at about 90-95°C for 1 h (Scheme 9.1.5) (25). The resulting brownish colloidal dispersions are stable and neither precipitate nor flocculate over a period of several years. Pd/ Pt bimetallic nanoparticles thus obtained have a so-called core/shell structure, which is proved by an EXAFS technique (described in Section 9.1.3.3). 

Amphiphilic poly[()V-vinyl-2-pyrrolidone)-h-poly(D,L-lactide)] was previously prepared by the authors (1) and used in drug device applications. 

Table 1. Incidence of neoplasms in V-vinyl-2-pyrrolidone-treated Sprague-Dawley rats...

In comparison to nematic liquid crystals, examples of smectic liquid crystals doped with quasi-spherical nanoparticles became more elusive over the last few years. This is surprising especially considering recent work by Smalyukh et al., who found that nanoscale dispersion (based on /V-vinyl-2-pyrrolidone-capped gold nanoparticles with 14 nm diameter) in a thermotropic smectic liquid crystal (8CB) are potentially much more stable than dispersions of nanoparticles in nematics [367]. 

Kitano, S., Koyama, Y., Kataoka, K., et al. A novel drug delivery system utilizing a glucose responsive polymer complex between poly (vinyl alcohol) and poly( V-vinyl-2-pyrrolidone) with a phenylboronic acid moiety. J. Contr. Rel. 19 161—170, 1992. 

VP V-vinyl-2-pyrrolidone PVP polyVP EGDMA ethylene glycol dimethacrylate BA butyl acrylate TPT 1,1,1-trimethylolpropane trimethacrylate NIPA V-isopropyl acrylamide AA acrylic acid BIS VV-methylene bisacrylamide PVA polyvinyl alcohol EDTAD ethylenediamine-tetraacetic dianhydride PEGDA polyethyleneglycol diacrylate PETA pentaerythritol triacrylate. 

HEMA 2-hydroxyethyl methacrylate VP V-vinyl-2-pyrrolidone TBCM 4-t-butyl-2-hydroxycyclohexyl methacrylate SVC silicone vinyl carbamate VA vinyl alanine NFMA V-formyhnethyl acrylamide EDMA ethylene dimethacrylate MAA methacrylic acid MCOE-PC 2-metha-cryloyloxyethyl-phosphorylcholine. 

Davis, T.P. Huglin, M.B. Yip, D.C.F. Properties of poly(V-vinyl-2-pyrrolidone) hydrogels crosslinked with ethyleneglycol dimethacrylate. Polymer 1988, 29, 701-706. 

Blanco, M.D. Trigo, R.M. Teijon, C. Gomez, C. Teij6n, J.M. Slow releasing of ara-C from poly(2-hydroxyethyl methacrylate) and poly(2-hydroxyethyl methacrylate-co-V-vinyl-2-pyrrolidone) hydrogels implanted subcutaneously in the back of rats. Biomaterials 1998, 19, 861-869. 

Poly(/V-vinyl-2-pyrrolidone), PVP, is available in various molecular weights (10,000, 40,000, 160,000, and 360,000) and can yield solutions of varying viscosities. PVP is best known for its unusual complexing ability toward many types of small molecules and for its physiological inertness [19], As a thickener, it is used in biomedical, pharmaceutical, cosmetic, and personal care products (hair styling gels, shaving creams, shampoos, emollient creams and lotions, etc.). 

Colloidal metal clusters, which offer a high surface area for better activity, have been stabilized by polymers. Thus, a homogeneous dispersion of a cobalt-modified platinum cluster was stabilized by a coordinating polymer, poly(/V-vinyl-2-pyrrolidone).74 Addition of the cobalt(II) [or iron(III)] doubled the activity and increased the selectivity from 12 to 99% when the catalyst was used to reduce cin-namaldehyde (5.23). 

Redox processes. Hydrodehalogenation of organic halides is done using PdCh anchored on poly((V-vinyl-2-pyrrolidone) as catalyst. On the other hand, benzils are obtained from diarylacetylenes in the presence of PdCU and DMSO. 

Oxidative Matrix Polymerization The polymerization of NVK in a matrix of poly(ethylene glycol) (PEG) has been described. As an oxidant, Ce" + has been used. PEG proved to be a more suitable matrix in order to obtain a stable homogeneous ternary complex solution in comparison to poly(acrylic acid) and poly(V-vinyl-2-pyrrolidone). 

By irradiation with UV light, crosslinking and chain scission in the base membrane material occurs. Crosslinldng increases the hydrodynamic resistance of the membrane. Chain scission is responsible for the loss of membrane selectivity. The presence of a monomer during UV irradiation, such as V-vinyl-2-pyrrolidone (NVP) seems to retard the loss of membrane selectivity. 

Solok EK, Sanli O. 2008. Separation characteristics of dimethylformamide/water mixtures using sodium alginate-g-V-vinyl-2-pyrrolidone membranes by pervaporation method. Chem. Eng. Process. 47 633-641. 

DI1 Dincer, S., Rzaev, Z.M.O., and Piskin, E., Synthesis and characterization of stimuli-responsive poly(V-isopropylacrylamide-co-V-vinyl-2-pyrrolidone), J. Polym. Res., 13, 121,2006. 

Poly(V-vinyl-2-pyrrolidone) has been studied as a carrier for palladium in the hydrogenation of oleflns f and nitroaromatics, hydrodehalogenation of organic halides,f t and carbonylation of aUyl halides. - In these cases PVP mostly likely played the role of supporting in situ formed colloidal Pd, rather than that of a well-defined ligand. 

Nitroaromatics have been reductively converted into aryl carbamate with methanol under CO atmosphere catalyzed by palladium(II) anchored onto montmorillonite clay. Conversely, the same carbamates can also be obtained via oxidative carbonylation of amines with carbon monoxide and oxygen in the presence of a bimetallic catalyst PdCl2-MnCl2 supported on poly( V-vinyl-2-pyrrolidone).f ... 

Poly(vinyl pyrrolidone)/PLA Blends Poly(A/-vinyl pyrrolidone), poly(V-vinyl-2-pyrrolidone), or poly(vi-nyl pyrrolidone) (PVP), an amorphous, nonionic water-soluble synthetic polymer, is biocompatible and used... 

BAE Bae, W., Kwon, S., Byun, H.-S., and Kim, H., Phase behavior of the poly(vinyl pyrrolidone) + V-vinyl-2-pyrrolidone + carbon dioxide system, J. Supercrit. Fluids, 30, 127, 2004. 

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