Anion-trapping-type electrolytes

II. Anion-Trapping-Type Organoboron Polymer Electrolytes via... 

Ion-conductive properties of anion-trapping-type organoboron polymer electrolytes was evaluated after adding lithium salts (Fig. 3). In these systems, ionic conductivity of 3.05 X 10 s 5.22 X 10 6Scm 1 was observed at 50°C. This indicates... 

Interestingly, the nonpolyether-type polymer electrolyte 7 showed a relatively high lithium transference number of 0.47 in the presence of LiTFSI. This is possibly due to the absence of strong binding of ether oxygen to the lithium cation. Moreover, anion trapping of the boron atom is not retarded by coordination of oxygen to the... 

The lithium transference number (l,) of these organoboron polymer electrolytes was evaluated by combination of dc polarization and ac impedance methods, as reported by Evans et al44 (Table 1). The observed t+ at 30°C was 0.50-0.35, indicating that anions were significantly trapped in these systems. Owing to the stronger Lewis acidity of the alkylborane unit, alkylborane-type polymers showed relatively higher t+. 

This technique is a variant of CZE. A cationic or anionic surfactant compound, such as sodium dodecylsulphate, is added to the mobile phase to form charged micelles. These small spherical species, whose core is essentially immiscible with the solution, trap neutral compounds efficiently by hydrophylic/hydrophobic affinity interactions (Fig. 8.7). Using this type of electrophoresis, optical purity analysis can be conducted by adding cyclodextrins instead of micelles to the electrolyte. This is useful for separating molecules that are not otherwise separable. Under such conditions, the enantiomers form inclusion complexes of different stability with cyclodextrin (cf. 3.6). 

It is assumed that, in both models of electron stabilization in water-alkaline matrices, there are small cavities in which the neighbouring water molecules are directed to each other with atoms of the same nature (with hydrogen atoms) while energetically the contact of atoms of different nature (i.e. H and O capable of forming a hydrogen bond) would be more favorable. For concentrated solutions of electrolytes, however, one should expect a considerable fraction of the water molecules to enter solvation shells of anions and cations. Under these conditions it seems quite probable that traps of the type depicted in Fig. 2(b) are formed in the contact sites of the solvation shells of two or several cations. This suggestion is supported by the... 

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