Lm. Ding et al., STUDIES ON THE 2 CLASS GLASS-TRANSITION A ND THE TYPICAL VTF BEHAVIOROF AN AMORPHOUS COMB POLYMER ELECTROLYTE, Gaodeng xuexiao huaxue xuebao, 17(10), 1996, pp. 1644-1648
A comb polymer (CP350) with oligo-oxyethylene side chains of the type
-(CH2CH2O)(7)CH3 was prepared from methyl vinyl ether/maleic anhydride
copolymer and poly(ethylene glycol) methyl ether. The polymer can dis
solve LiNO3 salt to form homogeneous amorphous polymer electrolyte. Th
is electrolyte system was first found to have two class glass transiti
ons, and the two T(g)s were observed to increase with increasing salt
content. The ionic conduction was measured by using the complex impeda
nce method, and conductivities were investigated as functions of tempe
rature and salt concentration. At 25 degrees C, the ionic conductivity
maximum of this system can get to 3.72 X 10(-5) S/cm at the [Li]/ [EO
] ratio of 0.057. The appearance of the conductivity maximum has been
interpreted as being due to the effect of T-g and the so called physic
al crosslinks. The temperature dependence of the ionic conductivity di
splaying non-Arrhenius behaviour can be analyzed using the Vogel-Tamma
nn-Fulcher equation and interpreted on the basis of the configurationa
l entropy model.