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The conductivity and dielectric relaxation behaviour of a glass-forming monoepoxide, cresyl glycidyl ether (CGE), were studied from to by impedance spectroscopy, in the temperature interval 83 - 333 K. Data analysis indicated the existence of a transition temperature marking the separation between two different relaxation regimes, in accordance with previous results given by Stickel and co-workers. The temperature is well above the glass transition temperature , and coincides with the temperature at which the timescales of the main and secondary relaxation processes coincide, so at there is a unique overall relaxation process. The splitting layout of CGE differs from that of the very common diepoxide diglycidyl ether of bisphenol-A (DGEBA), studied previously, and also the relaxation at high temperature has a correspondingly different dynamical behaviour. The relaxation strength behaviour is also analysed and compared with that of DGEBA; the similarities are discussed.

The dielectric behavior of an epoxide/ethylenediamine formulation has been studied during cross‐linking in the frequency range 103−1010 Hz at 25°C and 70°C. Dielectric data were collected both in the frequency and in the time domains and analyzed in terms of a combination of two Havriliak‐Negami functions. A complete description of the evolution of the relaxation parameters during the reaction was obtained. The nature of the information yielded by dielectrometry on the dynamics of the system is discussed. © 1995 John Wiley & Sons, Inc.

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