The measurement and modeling of the dielectric response of molecules during curing of epoxy resin

Results of dielectric measurements as a function of frequency are presented for the curing of an epoxy resin. By considering the change in the time occurrence of the peak in magnitude of the dissipation factor, and also by comparing this with the results for the cured resin, it is concluded that such peaks are not the result of either gelation or an alpha -relation process. The results were interpreted on the basis of a model considering the growing polymer dipoles to be in solution, the solvent being the unreacted monomer and hardener. If simplifying assumptions are made, it proved possible to estimate the activation energy for the curing process. The value of 41 kJ/mol (0.42 eV) compared favorably with the results obtained by other workers for similar systems.<
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