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The ionic structure and transport properties of amorphous solid polymer electrolytes in the system copolymer of acrylonitrile and butadiene (40 : 60)-lithium hexafluoroarsenate (SPE) is studied in the region of small salt concentrations (up to 0.37 mol dm -3 ) at 298-368 K. In conditions studied, LiAsF 6 is dissociated predominantly to ions. Macroscopic models of ion transport are used to analyze the results of measurements of transport characteristics of SPE. Transport of anions free of the polymer matrix is realized activationlessly and resembles the Stokes drift in viscous media. Transport of cations solvated by electron-donating groups of the polymer turns possible only at temperatures in excess of a critical value ( T crit ≈ 333 K), when the statistical mean of molecules in the first coordination sphere of the lithium cation becomes less than four (which is the coordination number for solvation) and requires the overcoming of an energy barrier of ~6 kJ mol -1 . Below T crit , the SPE are unipolar anionic conductors.

Abstract. The systems poly(butadiene-co-acrylonitrile) (PBAN) -lithium salts have been studied by means of X-ray and IR spectroscopy, optical microscopy and ac-and dc-conductivity measurements. X-ray and microscopy studies have confirmed that PBAN dissolves LiC104 up to [CN]/[Li] = 2: 1. IR spectra of the samples with LiAsF 6, LiCF3SO 3 and LiC104 have indicated the coordination between Li § and the polar CN groups of PBAN. So, PBAN was found to be a suitable polymer matrix for SPE. The polymer films exhibited predominant ionic conductivity. Measurements of conductivity and Li transport numbers versus temperature over a wide range of salt concentrations revealed the existence of two concentration regions (within the limits of salt solubility) corresponding to liquid-like and glass-like ion transport mechanisms. New solid polymer electrolyte with lithium single-ion conductivity of 10 .3 S cm "1 at 25 -95 ~ was obtained.

Abstract-Nanocomposite hybrid films containing silicon and titanium compounds in the polymer matrix are prepared through the sol gel method via the hydrolytic polycondensation of Si and Ti alkoxides (tetra ethoxysilane and titanium tetrabutoxide) in the THF solution of a hydrophobic polymer, ethyl cellulose. Their structure and properties are studied with the use of a complex of physicochemical methods. During the hydrolysis of tetraethoxysilane and the subsequent polycondensation of the reaction products, silicon atoms are incorporated into the polymer and form -O-Si-O-bonds involving hydroxyl groups of ethyl cellulose. In the sol gel method, titanium alkoxide yields nanosized particles of titanium dioxide that play the role of fillers in the polymer matrix. Titanium containing films show solubility in THF and, after prolonged contact with the solvent, precipitate titanium dioxide from the solution. Hybrid films containing silicon are insoluble owing to the formation of a chemical network between polymer molecules and Si-OH groups of the products of hydrolysis of silicon alkoxide, as confirmed by the IR data. It is shown that the amounts and types of alkox ides and the diameters of the structures formed in the polymer matrix via the sol gel procedure affect the hydrophilicity levels of ethyl cellulose hybrid films and their abilities to swell in water and aqueous solutions of organic dyes (brilliant blue and methylene blue). Ethyl cellulose hybrid films are hydrophilic, and they facilitate the removal of dye molecules from aqueous solutions. The best properties are featured by the films containing nanosized particles of titanium dioxide in the polymer matrix.