Relaxations in poly (etherimide) PEI Ultem 1000 have been analysed by differential
scanning calorimetry (DSC), dynamic mechanical spectroscopy (DMS), dielectric relaxation
spectroscopy (DRS) and thermally stimulated depolarization current (TSDC) measurements.
DMTA and DRS results show three distinct relaxations γ, β and α in the temperature range‐
140 to 250° C. The first one depends strongly on the water content in the sample as will be
discussed in more detail in the second paper of this series. These results are in good …

The curves describing the relaxation behaviour of poly (etherimide) at several frequencies
shows in the dielectric loss–temperature plot γ and β relaxations centred at‐95° C and 100°
C, respectively, at 10Hz. The glass–rubber relaxation or α process appears at 225° C at
10Hz; at this temperature free charge conductivity and blocking electrode phenomena
become dominant at frequencies below 10Hz. The same three relaxations are observed by
dynamic mechanical thermal analysis (DMS). The strength of the γ and α relaxations can be …