This paper describes our strategies to engineer amorphous polymer-salt comp
lexes and investigate their electrical behavior. In the first approach, sem
icrystalline polymer polyoxyethylene (POE) was plasticised using amorphous
polyoxypropyleneglycol (POPG) in the presence of sodium salts. In the secon
d approach. amorphous polymers, poly(bis(methoxyethoxyethoxy phosphazene))
(MEEP) and polysiloxane, were used to synthesise electrolytes. These were c
omplexed with sodium salts and a small amount of polyoxyethylene. The natur
e of each complex was ascertained from optical microscopy, X-ray diffractio
n (XRD) and Differential Scanning Calorimetry (DSC) in these systems. The p
olymer-salt complexes, in the first approach, revealed a well-defined glass
formation region in which all the compositions were amorphous and showed u
nusually high ionic conductivity similar to 10(-4) (Omega cm)(-1) at ambien
t temperature. The electrolytes in the second approach showed a maximum con
ductivity of similar to 10(-5) (Omega cm)(-1). However, truly amorphous com
positions could not he obtained. The first approach of engineering reductio
n in crystalline phases appeared more effective in enhancing ionic conducti
vity. (C) 2000 Elsevier Science B.V. All rights reserved.