Viscoelasticity of entangled random polystyrene ionomers

Using literature data for entangled polystyrene ionomers, a sticky double reptation model is developed and tested that effectively accounts for distributions in both chain length and number of ionic groups per chain. The model predicts that if there are more ionic groups than entanglements, the classic Leibler double plateau will be observed, with modulus from ion associations plus entanglements transitioning to that of just entanglements, beyond the association lifetime. Whereas at low enough ion content, there are more entanglements than ionic groups, resulting in a single plateau, with modulus from ion associations and entanglements, that persists until the sticky reptation time of the chains.