Poly -imidazole complexes

As a further approach for novel electrolytes appropriate for selective cation transport, we have prepared poly(organoboron halide)-imidazole complexes.35 Even though boron-amine complexes are widely known materials reported by the early works of H. C. Brown et al.,52-54 they had not been investigated as solvents or electrolytes to the best of our knowledge. 

Figure 5 Temperature dependence of ionic conductivity for poly(organoboron halide)-imidazole complexes in the presence of various lithium salts.

Figure 6 VFT plots for poly(organoboron halide)-imidazole complexes. 

Table 2 VFT Parameters for Poly(organoboron halide)-imidazole Complexes...

In the case of Ag+, only two imidazolyl groups participate in complex formation, and the overall stability constant is log p2 = 8.00, about one order of magnitude larger than the overall formation constant of the Ag/imidazole complex (log p2 = 6.84). Complexes of Cu2 + with poly 4(5)-vinyl-imidazole, poly(N-vinyl-imidazole), and... 

The Cu complex again oxidizes to Cu + in air. It is interesting fliat oxidation of Cu bound to poly(l-vinylimidazole) is characterized by higher enthalpy and lower entropy compared to the low-molecular-weight imidazole complex. These differences are attributed to the changes in polymer hgand conformation as a result of Cu oxidation to Cu and is evidenced by viscosity measurements. It has been noted that copper ion doping in poly(ihioether) stabilizes the oxidation state of Cu and results in the formation of a Cu+-Cu + system with a potential of 1V in aqueous solution. ... 

PSSA Poly( 1-vinyl imidazole) Complex formation in water/ethanol (2/1 by vol) solution 983... 

Significant research has been directed toward the use of polyelectrolyte complexes as blood compatible materials. Several investigators found that water-insoluble polyelectrolyte complexes can suppress blood coagulation [487-490]. Davison and coworkers reviewed and studied the biological properties of water-soluble polyelectrolyte complexes [491] between quatemized poly(vinyl imidazole) or polyvinyl pyridine) and excess sulfonated dextran or poly(methacrylic acid). By forming complexes with a stoichiometric excess of anionic charge, a more compact conformation with anionic character was obtained. 

Fig. 4. Schematic representation of the structure of polymer-heme complexes the ferriheme complex with poly(4-vinylpyridine) (a), poly(L-lysine) (b), (c), or poly(7-benzyl-L-glutamate) with a pendant imidazole (d)...

Tsuchida et al. [33], synthesized Poly(l-vinyl and l-vinyl-2-methyl-imidazole) bound heme (iron-porphyrin) complexes as models for mimicking natural oxygen carriers such as hemoglobin. The reaction between AIBN polymerized poly(l-vinyl)imidazole, or poly(l-vinyl-2-methylimidazole) and Fe(III) protoporphyrin IX diethyl ester in DMF and small amount of Na2S204 yields the Fe(III) complex (Fig. 15),... 

Heme (7a) with poly(l-vlnyl-2-methyliraidazole) pH 10 in ethylene glycol Comparing hexa coordinated heme with poly(l-vinyl-imidazole) to hexa or penta coordinated heme with low molecular imidazoles the above mentioned polymer ligand metal complex is absorbing O2 reversible at 243 K. The UVA IS spectrum is a good indicator for what is occuring (Fig. 1) ... 

The first example for Method 2 was reported by Nishide and co-workers, who polymerised a metal complex of 1-vinylimidazole with l-vinyl-2-pyrollidone and divinylbenzene [8]. The metal-vinylimidazole complex was copolymerised, cross-linked with l-vinyl-2-pyrollidone by y-ray irradiation and the template metal ion was removed by treating the polymer complex with an acid. These poly(vinyl-imidazole) (PVI) resins adsorbed metal ions more effectively than the PVI resin prepared without the template. The number of adsorption sites and the stability constant of the Ni(II) complex were larger for the PVI resin prepared with the Ni(II) template, as seen by the smaller dissociation rate constant of Ni(II) from the resin. 

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