UV-cured caprolactone-based polyurethane acrylate (PUA) polymer blend electrolytes were prepared and characterised. To develop polymer electrolytes suited to ambient temperature, an ionically-conductive and reliable polymer electrolyte based on urethane acrylate resins synthesised from a fluorine-containing di-functional oligomer 6F ethoxylated diacrylate, a di-functional reactive diluent 1,6-hexanediol diacrylate for adjusting the viscosity, and a radical photo-initiator doped with a mixture of lithium salts were used. Free-standing flexible electrolyte films were prepared by UV-curing via free-radical photopolymerisation. The performance of the lithium polymer cell system (Li/PE(F4)/LiCoO2) was determined by electrochemical impedance spectroscopy, cyclic voltammetry, a galvanostatic recurrent differential pulse, chronocoulometry and chronoamperometry. The electrolyte with optimal amounts of fluorine-containing oligomer and optimal salt mixture content exhibited enhanced conductivity, showing a conductivity of 1.00 × 10 −4 S cm −1 at ambient temperature. The specific capacity, specific energy and specific power of a Li/PE(F4)/LiCoO2 cell were also determined.

Electrochemical reduction of two recently synthesized pyrimidine compounds 1-amino-5-benzoyil-4-phenyl-1H-pyrimidine-2-one (I), and 1-amino-5-benzoil 4-phenyl-1H-pyrimidine-2-thione (II) were investigated by cyclic volatmmetry at a hanging mercury drop electrode in aqueous methanol (36 % v/v) and in non-aqueous methanol. Aseries of cathodic peaks without the corresponding anodic peaks were observed for I. As the pH of the solution was increased some of the cathodic peaks overlapped resulting in the loss of the previously observed peaks. For II, three cathodic peaks and one anodic peak were observed in addition to those observed for I. The peak potentials shifted in the negative direction with increasing pH. This shift was measured over a large pH range (1.80 ? 12.30) to determine the pKa values of the compounds. The acidity constants related to the amino groups were 4.80 and 9.80 for I and 5.50 and 9.80 for II. Athiol-thione tautomerization was observed for II which was more pronounced in the non-aqueous methanol medium. The pK values for both protonation and deprotonation of the thiocarbonyl group were also determined. The pK values were 5.80 and 9.80 for protonation and deprotonation in aqueous methanol and 6.80 and 10.80 in non-aqueous methanol.

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