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Poly quarternization

M. Yoshikawa, T. Yukoshi, K. Sanui, N. Ogata, Selective separation of water from water-ethanol solution through quarternized poly(4-vinyl pyridine-co-acrylonitrile) membranes by pervaporation technique, J. Appl. Polym. Sci. 33 (1987) 2369-2392. [Pg.57]

Heme (7a) with partly quarternized poly(4-vinylpyridine) in H2O/DMF = 9 1 has a much higher half life in the presence of an electrolyte than with pyridine comidexes ... [Pg.55]

Co(n)- and Fe(II)chlorophyllins (8) with partly quarternized poly(4-vinylpyridine/ In aqueous solution at pH 10 the metal ions are easily oxidized. Fundamentally the rate of irrevet Ue oxygoiation is lO times slower for the polymer complex than with pyridine. [Pg.55]

Binyamin, Chen and Heller reported that wired enzyme electrodes constituted of glassy carbon electrodes coated with poly(4-vinylpyridine) complexed with [Os(bpy)2Cl] and quarternized with 2-bromoethylamine or poly[(iV-vinylimidazole) complexed with [Os(4,4 -dimethyl-2,2 -bypyridine)2Cl] or poly(vinylpyridine) complexed with [Os(4,4 -dimethoxy-2,2 -bypyridine)2Cl] quaternized with methyl groups lost their electrocatalytic activity more rapidly in serum or saline phosphate buffer (pH 7.2) in the presence of urate and transitional metal ions such as Zn and Fe " " than in plain saline phosphate buffer (pH 7.2). It was reported that as much as two-thirds of the current is lost in 2 h in some anodes. However, when a composite membrane of cellulose acetate, Nafion, and the polyaziridine-cross-linked co-polymer of poly(4-vinyl pyridine) quaternized with bromoacetic acid was applied, the glucose sensor stability in serum was improved and maintained for at least 3 days [27,50]. [Pg.344]

Bohmer, M.R. et al., Adsorption of partially quarternized poly (vinyl imidazoles) onto SiO2 and YjO, Colloids Surf. A, 99, 53,1995. [Pg.969]

Lee and Jopson, on the other hand, used a different approach involving poly(vinylpyridine) (PVP), which is fairly insensitive to electrons, but whose sensitivity could be improved by quarternizing it with methyl iodide. On irradiation of PVP with electrons, cross-links are generated in two steps. First, the methyl iodide splits off and is cleaved into radicals by a second electron. The methyl radicals so created produce backbone radicals that ultimately lead to cross-linking as shown in Scheme 6.12. °°... [Pg.224]

O QUARTERNIZED POLY-2-VP GRAFTED PVC QUARTERNIZED POLY-2-VP GRAFTED CELL AC... [Pg.260]

Scheme 2.26 Representative structure of quarternized poly(arylene ether sulfone)s. Taken from Ref. [120]. Scheme 2.26 Representative structure of quarternized poly(arylene ether sulfone)s. Taken from Ref. [120].
The hydrolysis of nitrophenyl sulphates is not, contrary to an earlier report, catalysed by poly(ethylenimine) derivatives, although that of dinitrophenyl sulphates is substantially enhanced by partly quarternized polymer. ... [Pg.333]

The closed packing in a polymer chain may lead to uncoordinated ligand groups. Poly(4-vinylpyridine) dissolved in an ethanol/water mixture results with Co-acetylaceto-nate in a degree of complexation of 0.7. The rate of formation of the Co(II)-complex in with R partly quarternized poly(4-vinylpyridine) decreases due to steric reasons as follows R = -CH3 > -CH2-C6H5 [88]. [Pg.677]

Figure 7.5 (a) Diffusion coefficient measured in salt-free dilute solutions of sodium polyjstyrene sulfonate) is independent of the concentration and molecular weight (different symbols, in the range between 5000 and 200,000 g/mol) of the polymer. (From Sedlak, M. and Amis, E.J., J. Cbem. Pbys., 96, 817, 1992b. With permission.) (b) Diffusion coefficient decreases with salt concentration for the upper branch (fast mode). The lower branch is the slow mode. The data are for quarternized poly(vinyl pyridinium) salt with the molecular weight of 200,000 g/mol at different salt concentrations (squares, 10" M triangles, 10 M diamonds, 10" M and open circles, 0.1 M). (From Forster, S. et al.. Polymer, 31,781, 1990. With permission.)... [Pg.195]

A number of hydrophobically modified water-soluble polymers have been prepared via post-polymerization reaction. For example, Straus [21] has prepared polysoaps by the quarternization of poly(2-vinylpyridine) with n-dodecyl bromide (Eq. 1.3). [Pg.8]


See other pages where Poly quarternization is mentioned: [Pg.309]    [Pg.309]    [Pg.629]    [Pg.200]    [Pg.201]    [Pg.204]    [Pg.56]    [Pg.344]    [Pg.260]    [Pg.12]    [Pg.98]    [Pg.60]    [Pg.566]    [Pg.302]    [Pg.55]    [Pg.334]    [Pg.685]    [Pg.148]    [Pg.512]    [Pg.194]    [Pg.60]   
See also in sourсe #XX -- [ Pg.203 , Pg.204 , Pg.205 , Pg.215 ]




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Quarternization

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