Poly-2-vinylpyridinium

Marie P, Herrenschmidt YL, Gallot Y. Study of the emulsifying power of the block copolymers polystyrene/poly(2-vinylpyridinium chloride) and polyisoprene/poly(2-vinylpyridinium chloride). Makromol Chem 1976 77 2773-2780. 

In PVA-coated capillaries it was possible to separate at pH 2.5 the standards of poly-2-vinylpyridinium hydrochloride (p(2-VPy)) in the molecular mass range between 1500 and 1,730,000 g mol-1 with dextran T70 as sieving matrix [20]. An example is shown in Fig. 4, where a 5% solution of dextran T70 has been used. The efficiency of the monomolecular basic marker 4-aminopyridine is excellent, demonstrating the exclusion of secondary adsorptive effects at the capillary surface. Hence, the broad peaks of the polymeric standards are due to their polydispersity. As in CE the width of the peaks depends on their migration velocity through the detection window, no direct comparison of broadness of the individual peaks and analyte polydispersity is possible. However, for each individual peak the methods applied in SEC for calculation of the different molecular mass averages can be applied. 

Varoqui R, Tran Q, Pefferkorn E. Polycation-polyanion complexes in the linear diblock copolymer of poly(styrene sulfonate) poly(2-vinylpyridinium) salt. Macromolecules 1979 12 831-835. 

In addition to the side chain conformation, chemically different side chains attached to the same main chain may also have a pronounced impact on the main chain conformation, particularly if the respective side chains are incompatible. Demixing of the side chain is hampered by the fact that the chemically different side chains are bound to the same main chain, leading to highly frustrated single chain structures. In order to experimentally address this point, the phase separation within statistical cylindrical brush copolymers comprising PMMA and poly-2-vinylpyridinium (PVP) side chains was investigated [93, 94]. The samples were prepared by radical copolymerization of methacryloyl end-functionalized PMMA M = 3,700 g/mol) and PVP M = 5,100 g/mol) macromonomers. Copolymer brushes with two different compositions were synthesized and characterized as shown in Table 1. Subsequent quatemization of the PVP side chains with ethylbromide was conducted in order to enhance incompatibiUty. 

Nash et al. (1966) synthesised another compound, polyvinylpyridinioacetic acid, which has even greater hydrogen bonding capacity than poly-2-vinylpyridine-l-oxide and very efficiently protects macrophages from silica toxicity. This protection was confirmed by Sakabe and Koshi (1967), who also showed that it prevents the increase in acid phosphatase in macrophages following exposure to silica. Holt et al. (1970) reported that some poly-2-vinylpyridinium salts prevented quartz toxicity in cultures. Thus the presence of hydrogen... 

In our investigation, we attempted to produce an emulsion system having no such defects by using water alone as solvent. Mario, et al. ) tried to prepare a "water in water" emulsion by mixing three water soluble poljmier solutions, [poly (oxyethylene), poly (2-vinylpyridinium chloride) and co-poly (2-vinyl pyridinium chloride)-poly (oxyethylene)] and developed a comparatively stable system. 

The mixture of the PAS and PEG aqueous solutions thus lost mutual solubility at more than given concentration and phased into two layers. Observation of a similar phenomenon was reported by Higashi ), et al., on a combination of poly (vinyl alcohol)/poly (ethylene oxide), poly (acrylamide)/poly (ethylene oxide), or poly (acrylamide)/ poly (acrylic acid) and so on. The aqueous solution of a combination of poly (2-vinylpyridinium chloride) and poly (ethylene oxide) was studied by M.M, Mario, et, al, and they made public a phase separation diagram of this system, which resembles the PAS/PEG system. The phase separation of the combination of two water soluble pol3nner mixtures was due to the result of the lost mutual solubility, and not of the formation of a polymer-pol3nner complex 3)4) such as poly (acrylic acid) and poly (ethylene oxide). 

The stability of water in water emulsions was studied by M.M. Mario, et. al., using poly (2-vinylpyridinium chloride) (PV2P) and PEG systems. They reported that a relatively great amount of a graft co-pol3nner of PV2P/PEG should be added for the stabilization of the emulsions. 

Gohy JF, Varshney SK, Antoun S, Jerome R (2000) Water-soluble complexes formed by sodium poly(4-styienesulfonate) and a poly(2-vinylpyridinium)-block-poly(ethyleneoxide) copolymer. Macromolecules 33 9298-9305... 

Gohy JF, Mores S, Varshney SK, Jerome R (2003) Self-organization of water-soluble complexes of a poly(2-vinylpyridinium)-block-poly(ethylene oxide) diblock with fluorinated anionic surfactants. Macromolecules 36 2579-2581. doi 10.1021/ma025665v... 

Gohy JF, Varshney SK, Jerome R (2001) Morphology of water-soluble interpolyelectrolyte complexes formed by poly(2-vinylpyridinium)-block-poly(ethyltaie oxide) diblocks and poly (4-styrenesulfonate) polyanions. Macromolecules 34 2745-2747. doi 10.1021/ma002131q... 

Protocols have been developed which utilize an insoluble solid catalyst in combination with dihydropyran to effect the protection of alcohols as their corresponding THP ethers. These procedures are advantageous in that the catalyst may be recovered by simple filtration and the products isolated by evaporation of volatiles. In many cases the catalyst can be reused without regeneration. Reaction of alcohols with dihydropyran in the presence of Amberlyst H-15 (25 °C, 1 h, 90-98%) yields THP derivatives. Alternatively, a solution of dihydropyran and the alcohol may be passed slowly through a column of silica overlaid with Amberlyst H-15 to yield the THP ethers directly (73-97%). The acidic clay Montmorillonite KIO (25 °C, 15-30 min, 63-95%) is similarly applicable, Reillex 425 resin (86 °C, 1,5 h, 84-98%) is applicable with the advantage that it does not promote the sometimes troublesome polymerization of dihydropyran. Polymeric derivatives of pyridinium p-toluenesulfonate are also effective. Poly(4-vinylpyridinium p-toluenesulfonate) and poly(2-vinylpyridinium p-toluenesulfonate) catalysts yield tetrahydropyranyl derivatives of primary, secondary, and tertiary alcohols (24 °C, 3-8 h, 72-95%). ... 

It has been also found that PhIO as an oxidant in the presence of a catalytic amount of sulfonated manganese and iron porphyrin supported on poly(vinylpyridinium) polymers in olefin epoxidation and alkane hydroxylation is a better oxidant than Bu4NHS05 °. Oxidation of adamantane to 1-adamantanol in good yield using BU4NHSO5 and acetone in the presence of aqueous NaHCOs was also reported . ... 

Poly(vinylpyridinium) salts, however, are only active if the quartz particle had been treated with them before its action. Poly(vinylimidazole) (25) is inactive, although it is as strongly adsorbed as PVNO. 

Poly(vinylpyridinium chlorochromate) (PVPCC) is a mild oxidant for primary, secondary, allylic and benzylic alcohols. Unfortunately, optimum conditions require the use of very nonpolar solvents (best is cyclohexane) at 80 C. More polar solvents (that would be more generally useful in synthesis) severely retard the rate of oxidation, thus necessitating an increase in the amount of oxidant used. Oxidations were found to have high inital rates, but were very slow to go to completion due to the inaccessibility of the chromium. This can be overcome by using a lower loading of oxidant or by an alternative preparation of the polymer, where the addition of 1-5% divinylbenzene gives a much more porous resin. 

Poly(vinylpyridinium dichromate) can be prepared in a similar way to PVPCC. To be effective it must be used in the presence of water and in the most noiq>olar solvent possible. It gives moderate to good yields, but long reaction times may be required for the reaction to proceed to completion. Even with die long reaction times, very little overoxidation is observed. Up to five oxidation-regeneration cycles may be completed without significant loss of activity. 

Considering the reactions between weak poiyeletrolytes, e.g. between PAA-poly-(dimethylaminoethyl methacrylate) and PAA-poly(vinylpyridinium bromide) the authors showed that the constant of salt formation K2 increases with rising degree of conversion 6. This reflects the cooperative character of interactions between polyelectrolytes. 

Poly(vinylpyridinium) chlorochromate (PVPCC) is obtained as a liright-orange solid by adding chromium trioxide and concentrated hydrochloric acid to an aqueous suspension of cross-linked poly(vinylpyridine) (PVP) resin (50-100 mesh). Oxidations of primary and secondary alcohols to carbonyl compounds are carried out on heating with a slight excess of the resin at 75-80 °C. The reaction is best carried out in cyclohexane [612]. 

It is possible to put mutually incompatible reagents in the same flask if each is on a separate resin. The reactions in 5.55 could be run in sequential fashion or simultaneously in cyclohexane. The reagent in the first step was poly (vinylpyridinium dichromate), in the second, a perbromide on a strongly basic resin (Amberlyst A26), and in the third,... 

Li XY, Olah GA, Prakash GKS, Wang Q. 1993. Poly -vinylpyridinium poly(hydrogen fluoride) A solid hydrogen fluoride equivalent reagent. Synthesis 7 693-699. 

The porosity of the poly(vinylpyridine) resin used is an important factor in determining the efficiency of oxidation of alcohols by poly(vinylpyridinium) chlorochromate and poly(vinylpyridinium) dichromate. Increased porosity also aids in recycling of the polymer-based reagents, which are easily handled in molar amounts. 

Figure 18. Sulphonated metalloporphyrins supported on poly(vinylpyridinium)polymers [325].

Polymer-bound oxidizing agents, such as chromium(VI) species, have many applications. Chromium in all oxidation states has been identified as carcinogenic. Poly(vinylpyridinium dichromate) (25) in cyclohexane at 70 °C gave high yields of aldehydes from primary alcohols, as in... 

Cationic hydrophobic Poly(4-vinylbenzyltrimethylammonium chloride), poly(N-methyl-2-vinylpyridinium) iodide salt 0.5 M acetic acid with 0.3 M Na2SO,... 

Cationic hydrophobic Polyethyleneimine Poly(N-methyl-2-vinylpyridinium) salt 0.5 M NaOAc/ 0.5 M AcOH... 

The first use of ionic liquids in free radical addition polymerization was as an extension to the doping of polymers with simple electrolytes for the preparation of ion-conducting polymers. Several groups have prepared polymers suitable for doping with ambient-temperature ionic liquids, with the aim of producing polymer electrolytes of high ionic conductance. Many of the prepared polymers are related to the ionic liquids employed for example, poly(l-butyl-4-vinylpyridinium bromide) and poly(l-ethyl-3-vinylimidazolium bis(trifluoromethanesulfonyl)imide [38 1]. 

Pyridinium ylide is considered to be the adduct car-bene to the lone pair of nitrogen in pyridine. The validity of this assumption was confirmed by Tozume et al. [12J. They obtained pyridinium bis-(methoxycarbonyl) meth-ylide by the photolysis of dimethyl diazomalonate in pyridine. Matsuyama et al. [13] reported that the pyridinium ylide was produced quantitatively by the transylidalion of sulfonium ylide with pyridine in the presence of some sulfides. However, in their method it was not easy to separate the end products. Kondo and his coworkers [14] noticed that this disadvantage was overcome by the use of carbon disulfide as a catalyst. Therefore, they used this reaction to prepare poly[4-vinylpyridinium bis-(methoxycarbonyl) methylide (Scheme 12) by stirring a solution of poly(4-vinylpyridine), methylphenylsulfo-nium bis-(methoxycarbonyl)methylide, and carbon disulfide in chloroform for 2 days at room temperature. 

Fig. 145.—Osmotic pressure-concentration ratios ( in g./cm and c in g./lOO ml.) for poly-(4-vinylpyridine) in alcohol, O, coordinates left and below poly-(N-butyl-4-vinylpyridinium bromide) in alcohol, coordinates right and above and the same polymer in alcoholic 0.61 N lithium bromide, 3 coordinates left and below. °> ...

A PRP -1 (Hamilton Reno, NV) reversed phase column was coated with cetylpyridinium and eluted with tetramethylammonium salicylate acetoni-trile water.89 The separation was comparable to that observed on conventional ion exchange. Coated phases were also used to separate oxalate complexes of manganese, cobalt, copper, and zinc.90 Reversed phase silica supports were coated with poly(N-ethyl-4-vinylpyridinium bromide), poly(dimethydiallylammonium chloride), poly(hexamethyleneguanidinium... 

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