Abstract
We examine the relevance of the strong-fragile classification scheme for glass-forming polymeric systems using results from Brillouin and photon correlation spectroscopy. The dynamics of salt doped polypropylene oxide (PPO) have been investigated in relation to induced local structural ordering. It is accomplished by forming complexes of NaCF3SO3-PPO in which the cations act as transient cross-links between chains. The amount of cross-links depends on salt concentration and temperature. This allows for a test of the suggested relation between structural properties and some characteristics of the relaxation function such as its non-exponential time decay and non-Arrhenius temperature dependence.