Temperature and pressure effects on molecular mobility and ionic conductivity in telechelics based on poly(ethylene oxide) capped with hydroxyl groups at both ends

Functionalized telechelics based on poly(ethylene oxide) capped with OH-groups, with protons (H+) in the terminals have been prepared and the effects of structure on molecular mobility and protonic conductivity have been investigated. Molecular mobility and protonic conductivity were measured by means of broadband dielectric relaxation spectroscopy (10−2–109 Hz). Pressure effects were also studied by using a multianvil apparatus to generate conditions up to 5 kbar. The features of relaxation, associated to the glass transition, and of dc conductivity σdc, determined from ac conductivity (σac(f)) plots, were analysed in detail. Protonic conductivity is governed by the motion of the polymeric chains, however a decoupling between translational and rotational motion is observed, as the temperature decreases towards the glass transition temperature. Dc conductivity was found to decrease with increasing pressure.