Poly(oxyethylene) (POE)/siloxane-based materials incorporating magnesium triflate (Mg(CF 3 SO 3) 2) were synthesized by the sol-gel process. The host Class II hybrid matrix (diureasil) employed is composed of a siliceous framework to which short POE chains are covalently bonded through urea linkages. Ormolytes with salt composition n (molar ratio of oxyethylene moieties per Mg 2+ ion) ranging from ! to 1 were investigated. The nanohybrid with n = 20, which is thermally stable up to 360 ºC, exhibits the highest conductivity (e.g., approximately 4.0x10-6 and 6.7x10-5 "-1 cm-1 at 35 and 104 ºC, respectively). The redox stability domain of this material spans from-3.0 to +2.0 V versus Mg/Mg 2+ .

The results of an investigation of a polymer electrolyte system based on the poly(trimethylene carbonate) host matrix, designated as p(TMC), with lithium tetrafluoroborate guest salt are described in this presentation. Electrolytes with lithium salt compositions with n between 3 and 80 (where n represents the number of (O=COCH 2 CH 2 CH 2 O) units per lithium ion) were prepared by co-dissolution of salt and polymer in anhydrous tetrahydrofuran. The homogeneous solutions obtained by this procedure were evaporated, within a preparative glovebox and under a dry argon atmosphere, to form thin films of electrolyte. The solvent-free electrolyte films produced were obtained as very flexible, transparent, completely amorphous films and were characterized by measurements of total ionic conductivity, cyclic voltammetry, differential scanning calorimetry and thermogravimetry.

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Poly(oxyethylene) (POE)/siloxane hybrids (di-ureasils) doped with a wide concentration range of lithium triflate (LiCF 3 SO 3) were investigated. The host matrix of these materials (d-U(2000)) is a sol-gel derived siliceous framework to which POE chains with about 40.5 repeat units are bonded through urea linkages. Xerogels with ∞ ≥ n ≥ 5 (n is the molar ratio OCH 2 CH 2 /Li +) were obtained as amorphous monoliths thermally stable up to at least 340 ºC.

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