This work constitutes an innovative approach in epoxy based polymer characterization, where complementary physico-chemical, electric and structural techniques are used. The main objective of these studies is to understand both dielectric phenomena and properties associated to the space charges, as well as to follow-up their evolution in time or after the application of external constraints.Impedance spectroscopy and thermo-stimulated depolarization current (TSDC), measurements have highlighted dipolar and interfacial relaxations processes. Origin of these phenomena has been explained from physico-chemical and structural analyses. First, X-ray fluorescence measurements revealed the presence of two types of impurities, which are able to create deep energetic levels in the forbidden energy band. Then, X ray reflectometry measurements highlighted several periodic structures within an amorphous matrix. This structural heterogeneity explains the mechanisms of trapping and accumulation of space charges at the interfaces and gives a first reply as for the relatively high value of the polymer electric conductivity, calculated from current-voltage measurements.Accelerated ageing studies have been also carried out. They have shown that annealing creates charges which are trapped in increasingly deep energetic levels. Consequently, both the quantity of released charges and annealed samples conductivities have decreased.These electric properties changes have been correlated with the structural changes occurring within the polymer, and whose principal manifestation is the progressive disappearance of the ordered structures. This disappearance of the local periodicity has also been observed in the absence of thermal constraints (natural ageing), where it was shown that samples surface’s behavior is different from the bulk.
