Polymerizable imidazolium acrylates and their polymers with pendant imidazolium cations were synthesized with hexafluorophosphate and bis(trifluoromethanesulfonyl)imide counterions and characterized using calorimetry and dielectric spectroscopy. The ionic polymers containing a diethyleneoxy unit as an N-substituent on the imidazolium cation display higher ionic conductivities than the analogous N-n-butyl polymers. Using a physical model of electrode polarization, we separate the conductivity of single-ion conductors into number density of conducting ions p and their mobility μ. The monomers invariably possess higher conducting ion number density than the polymers, owing to the cation being part of the polymer, but p is insensitive to the N-substituent. In contrast, the diethyleneoxy N-substituent imparts higher mobility than the n-butyl N-substituent, for both monomers and polymers, owing to a lower binding energy between the imidazolium and the counteranions, which is not directly reflected in glass transition temperatures.
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)
- Materials Chemistry