Poly-4 -vinylimidazole

The kinetic characteristics of the solvolysis of long-chain phenyl esters catalyzed by polyvinylimidazole are totally different from those of simpler substrates. Over-beiger etal found a dramatic rate enhancement for the solvolysis of NDBA13 catalyzed by poly-4-vinylimidazole 1 in ethanol-water mixture (5S). The reaction obeys the Michaelis-Menten kinetics when the ethanol content is below ca. 40%, while solvolyses in 60,70, and 80% ethanol are satisfactorily described by a simple second-order rate equation. In term of the half-life, t fi, the solvolysis in 20% ethanol... 

Fig. 4-4. A schematic illustration of the conformation of poly(4-vinylimidazole) in ethanol-water.

In the polyvinylimidazole-catalyzed solvolysis of NDBA, retardation behavior was noted for [NDBA] > [PVIm] and acceleration behavior for [PVIm] > [NDBA]. These results were related to the formation of the long-lived intermediate, dodecanoyi-poly-4-vinylimidazole 14 (55). 

Bozkurt A and Meyer W H (2(X)1) Proton conducting blends of poly(4-vinylimidazole) with phosphoric acid. Solid... 

The metalloporphyrin complexes and their derivatives have been studied from the standpoint of model compounds of hemoglobin. The polymer-metalloporphyrin complexes are also formed by the reaction in Scheme 8, and a few qualitative investigations have been made with poly(L-lysine)9,10, poly(L-histidine)11, and poly(vinylimidazole)12 as the polymer ligand. Blauer9 has studied the complex formation of heme with poly(L-lysine) and has discussed the effects of the molecular weight and secondary structure of poly(L-lysine) on complex formation. 

It should be mentioned that polyvinylpyrrolidone (PVP) 87 and polyvinylpyrrolidone-poly vinylimidazole (PVP/PVI) copolymers are used... 

Thus one might expect flexible, water-soluble synthetic polymers with suitable side chains to show affinities for small molecules. We have examined, over several decades, the binding ability of poly(vinylpyrrolidone), polyvinylpyridine, polylysine, polyacrylamide, poly(isopropylacrylamide), poly(vinylimidazole), poly(vinylmethyloxazolidi-none), poly(vinylmethyloxazolidinone-vinylimidazole), poly(vinylpyrrolidone-vinyli-midazole), poly(vinylpyrrolidone-vinyl alcohol), poly(vinylpyrrolidone-maleic anhydride), poly(vinylmethyloxazolidinone-maleic anhydride), and poly(2-methylami-noethyl methylacrylate-methacrylic acid). Other investigators have studied similar synthetic polymers [5-12], In our experience no water-soluble polymer binds small molecules with an avidity comparable to serum albumin. 

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. 

Branched and linear polyethylene imine), and poly(vinylimidazole), were similarly cross-linked in the presence of template Cu2+ or Co2+ ion, but no enhancement of selectivity towards the same metal ions was achieved 37>. 

Fe II,III)-tetrakis[o-(alkylamido)phenyl)porph3nins (iJ) with poly(vinylimidazole-co-sty-rene) or triblock polymer tike polyethylen ycol-poly(l-vinylimidazole-co-styrene)-polyethy-lenglycol containing thiophenoi bridges between the blocks -... 

Cabot, B., Deratani, A., and Foissy, A., Adsorption of poly(vinylimidazoles) onto silica surfaces. Colloids Suif. A, 139, 287, 1998. 

Still, there is the most interesting phenomenon that the cationic polymer poly(iV-hexadecyl-/V,/V-dimethy-N-vinylbenzyl ammonium chloride) 28 exhibits very low reduced viscosities but does not show polyelectrolyte behaviour in aqueous solution [103, 292] the plot of reduced viscosity vs concentration is strictly linear, and is insensitive to added salt (Fig. 20). Importantly, this head type vinyl polymer without main chain spacer is not water-soluble and thus not a true polysoap, but forms only metastable aqueous solutions (see Sect 2.2.4). Similar results were reported for alkylated poly(vinylimidazoles) such as 26 [347], It may be speculated that such solutions represent rigid molecular latexes rather than flexible polymeric micelles , and further studies on such systems would be most interesting. 

The conventional polymers used are polyethylene,52 polystyrene,53 poly-(vinylimidazole),54 poly(acrylonitrile),55 or polyphosphazene.56 Figure 3.8 shows... 

Huang et al. described a simple, rapid method for the quantitative monitoring of five sulfonamide antibacterial residues in milk. The analytes were concentrated by SBSE based on poly(vinylimidazole-divinylbenzene) monolithic material as coating, and analyzed by HPLC with diode-array detection. The extraction procedure was very simple. Milk was first diluted with water and then directly subjected to sorptive extraction without a requirement for additional steps to eliminate fats and protein in the samples. Under the optimized experimental conditions, low detection limits (S/N = 3) (where S/N = signal-to-noise ratio) and quantification limits (S/N = 10) were achieved for the target compounds within the range of 1.30-7.90 and 4.29-26.3 p.g/1 from spiked milk, respectively. Good linearities were obtained for the sulfonamides with correlation coefficients (R ) above 0.996. Finally, the proposed method was successfully applied to the determination of sulfonamides in different milk samples. 

Tsuchida and co-workers (97) tried similar crosslinking with branched and linear poly(ethylene imin ) and W th poly(vinylimidazole) in the presence of Cu or Co ion templates, but no enhancement of selectivity towards the same metal ions was achieved. The same was true when they prepared a polymer from a monomeric complex (98). In this case the metal-1-vinylimidazole complex (from Ni, Co or Zn as the template) was copolymerized and crosslinked... 

Casting the complex solution of a metalloporphyrin and a polymer ligand such as poly(vinylimidazole-co-alkylmethacrylate) (Olm in Fig. 9-8), for example, on a Teflon plate and drying, yielded both a homogenously dispersed metalloporphyrin in a solid state and a mechanically tough membrane [26]. The Tg of the membrane was increased, for example, from -1 °C for the Olm itself to 6 °C and the membrane became brittle after the incorporation of 40 wt.% cobalt porphyrin this was explained by the stiffening effect of the incorporated... 

The acid-base Nafion composite membranes include blends of Nafion with polypyrrole (PPy) [98-104], polybenzimidazole (PBI) [105-107], poly (propyleneoxide) (PPO) [108, 109], polyfurfuryl alcohol (PFA) [110], poly(vinyl alcohol) (PVA) [111-115], sulfonated phenol-formaldehyde (sPF) [116], polyvinylidene fluoride (PVdF) [117-122], poly(p-phenylene vinylene) (PPV) [123], poly(vinyl pyrrolidone) (PVP) [124] polyanifine (PANI) [125-128], polyethylene (PE) [129], poly(ethylene-terephtalate) [130], sulfated p-cyclodextrin (sCD) [131], sulfonated poly(ether ether ketone) (sPEEK) [132-135], sulfonated poly(aryl ether ketone) (sPAEK) [136], poly(arylene ether sulfone) (PAES) [137], poly(vinylimidazole) (PVl) [138], poly(vinyl pyridine) (PVPy) [139], poly (tetrafluoroethylene) (PTFE) [140-142], poly(fluorinated ethylene-propylene) [143], sulfonated polyhedral oligomeric silsesquioxane (sPOSS) [144], poly (3,4-ethylenedioxythiophene) (PEDT) [145, 146], polyrotaxanes (PR) [147], purple membrane [148], sulfonated polystyrene (PSSA) [149, 150], polystyrene-b-poly(ethylene-ran-butylene)-bpolystyrene (SEES) [151], poly(2-acrylamido-2-methyl-l-propanesulphonic acid-co-l,6-hexanediol propoxylate diacrylate-co-ethyl methacrylate) (AMPS) [152], and chitosan [31]. A binary PVA/chitosan [153] and a ternary Nafion composite with PVA, polyimide (PI) and 8-trimethoxy silylpropyl glycerin ether-1,3,6-pyrenetrisulfonic acid (TSPS) has also been reported [154]. 

B. R. Green and E. Jaskulla, Poly(vinylimidazole)—A Versatile Matrix for the Preftaration of Chelating Resins, in D. Naden and M. Streat (Eds.), Ion Exchange Technohgy Eliis Horwood, London, 1984. 

---