Abstract :
Ion-conducting polymers have a biphasic character with crystalline as well as amorphous phases. There is moreover, a dynamic disorder due to motion of polymer chain segments. The PEO-NH4ClO4 system undergoes a crossover from a DLA-type morphology for low salt fraction (X) to a structure with polygonal spherulites. In the present communication we show that the low X regime exhibits a variation of diffusivity with crystallinity typical of a quenched system, whereas the high X regime has dynamic disorder with rapid rearrangement.