Studies on comb-like polymer blend with poly(ethylene oxide) lithium perchlorate salt complex electrolyte

Comb-like polymer having poly(ethylene oxide) (PEO) side chain was synthesized from the macromer poly(ethylene glycol) ethyl ether methacrylate (PEGEEM). Copolymers of PEGEEM with hydrophobic methyl methacrylate (MMA) of varying compositions were also synthesized. The copolymers were characterized by H-1 n.m.r. Hybrid film of polyelectrolyte was prepared from these polymers with PEO and LiClO4 by the solution cast technique. Ionic conductivities were studied by the impedance method for these hybrid films with respect to MMA percentage and salt concentration. It was found that the conductivity at high frequency semi-circle (sigma(h)) was independent of MMA concentration, while the bulk (sigma(d)) conductivity was higher than the PEG-salt complex up to 20-30% of the MMA concentration. The salt variations in hybrid films showed that the ionic conductivity for (ethylene oxide), EO/Li = 8 was lower than that for EO/Li = 12 and 20. (C) 1997 Elsevier Science Ltd.