Poly-4-vinylpyridine-N-oxide

Ernst H, Rittinghausen S, Bartsch W, Creutzenberg O, Dasenbrock C, Gorlitz BD, Hecht M, Kairies U, Muhle H, Muller M, Heinrich U, Pott F (2002) Pulmonary inflammation in rats after intratracheal instillation of quartz, amorphousSiO(2),carbon black, and coal dust and the influence of poly-2-vinylpyridine-N-oxide (PVNO). Experimental and Toxicologic Pathology 54 109-126. 

Fromme etal. (1966) localised tritiated poly-2-vinylpyridine-N-oxide of about 55kDa injected subcutaneously into rats (FW 49) on the surface of tridymite dust given into the peritoneal cavity 0, 3, or 5 d before. The free radical scavenging properties of PVPNO may be a mechanism for its action in pneumoconiosis (Gulumian and van Wyk 1987). 

Since the applied poly(vinylpyridine)s are only soluble in form of their salts in acidic solution and, therefore, precipitate in the organism of the animal after injection, the application of the corresponding N-oxides, like poly(2-vinylpyridine-l-oxide) PVNO [2] constitutes a decisive improvement (19). 

Au NPs have been synthesized in polymeric micelles composed of amphiphilic block copolymers. Poly(styrene)-block-poly(2-vinylpyridine) in toluene has been used as nanocompartments loaded with a defined amount of HAuCl4 and reduced with anhydrous hydrazine. The metal ions can be reduced in such a way that exactly one Au NP is formed in each micelle, where each particle is of equal size between 1 and 15 nm [113]. In another example, the addition of HAuCfi to the triblock copolymer (PS-b-P2VP-b-PEO) (polystyrene-block-poly-2-vinyl pyridine-block-polyethylene oxide) permits the synthesis of Au N Ps using two different routes, such as the reduction of AuC14 by electron irradiation during observation or by addition of an excess of aqueous NaBH4 solution [114]. 

A very interesting technique that has been used widely in the MTO-catalyzed olefin oxidation reaction is the microencapsulation technique. This technique uses poly(4-vinylpyridine) (PVP), either 2% or 25% cross-linked with divinylbenzene (PVP-2% or PVP-25%, Fig. 4), as well as poly(4-vinylpyridine-/V-oxide) (PVPN-2%, Fig. 4). In addition, 2% cross-linked PS (PS-2%, Fig. 4, X = CH2) and a mixture of PS-2% and PVP-2% (5 1, Fig. 4, X = N) have been used as support polymers. This approach is based on the physical envelopment of the Lewis-acidic MTO by the PS polymer, enhanced by interactions of the 7t-electrons of the phenyl rings with MTO. In the case of the pyridine-containing polymers, Lewis acid-Lewis base interactions between the pyridine moiety and MTO obviously play an important role. In the case of the PVP and PVPN polymers, MTO can be incorporated in the support matrix by mixing the polymer and MTO in ethanol to obtain the desired immobilized catalyst. 

PHMPA = poly(N,N-dimethyl-N N N"N"-tetramethylenephosphoric triamide), PM A A = poly-(methacrylic acid), PVPo = poly(N-vinyl-2-pyrrolidone), P2VP = poly(2-vinylpyridine), PEO = polyethylene oxide), PEI = poly(ethylenimine), PA Am = poly (acrylamide), PVA = poly (vinyl alcohol), PAA = poly(acrylic acid), PGA = poly(L-glutamic acid), P4VP = poly(4-vinylpyridine)... 

Bronstein, L. H., S. N. Sidorov, P. M. Valetsky, J. Hartmann, H. Colfen, andM. Antonietti. 1999. Induced micellization by interaction of poly(2-vinylpyridine)-block-poly(ethylene oxide) with metal compounds. Micelle characteristics and metal nanoparticle formation. Langmuir 15 (19) 6256-6262. 

The electroreduction of some typically inorganic compoimds such as nitrogen oxides is catalysed by the presence of polymeric osmium complexes such as [Os(bipy)2(PVP)2oCl]Cl, where bipy denotes 2,2 -bipyridyl and PVP poly(4-vinylpyridine). This polymer modifies the reduction kinetics of nitrite relative to the reaction at a bare carbon electrode, and provides calibration graphs of slope 0.197 nA with detection limits of 0.1 pg/mL and excellent short-term reproducibility (RSD = 2.15% for n = 20). The sensor performance was found to scarcely change after 3 weeks of use in a flow system into which 240 standards and 30 meat extracts were injected [195]. 

Koutalas G, Pispas S, Hadjichristidis N (2004) Micelles of poly(isoprene-h-2-vinylpyridine-h-ethylene oxide) terpolymers in aqueous media and their interaction with surfactants. Eur Phys J E 15 457 64... 

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