Solvation of lithium salts within single-phase dimethyl siloxane bisphenol-A carbonate block copolymer

Dimethyl siloxane bisphenol-A polycarbonate block polymer was evaluated for its ability to dissociate lithium salts within a single-phase polymer matr ix so as to invoke lithium ion conductivity. This strategy exploits the ide a that carbonate oxygen, within a single-phase carbonate-siloxane polymer m atrix, will facilitate extensive ionic dissociation of introduced lithium s alts, and that furthermore elastomeric behavior of the matrix under ambient temperature conditions will lead to enhanced mobility of lithium ions. Sin ce solvating capacity of the polymer matrix is dependent upon the presence of oxygen in a flexible molecular group dimethyl siloxane bisphenol-A polyc arbonate was chosen because it contains a carbonate oxygen within the polym er matrix and is a flexible polymer when cured. Ionic conductivities simila r to those reported for polyethylene oxide were observed due to the inclusi on of a plasticizer solvent and lithium salt into the dimethyl siloxane bis phenol-A polycarbonate matrix. (C) 2000 Elsevier Science Ltd. All rights re served.