The kinetics of water absorption in epoxide materials was studied by the aid of a diglycidyl ether of bisphenol‐A–triethylenetetramine (DGEBA–TETA) epoxy–resin system containing various amounts of the plasticizer THIOCOL (0–40 phr). The presence of plasticizer permits the formation of products with different crosslinking densities and hydrophilic characters. Dynamic water absorption experiments were carried out at 15, 40, and 70°C. For the fitting of the experimental results, a new model was used, based on a model proposed earlier by Jacobs and Jones. This model considers epoxide product as a two‐phase system consisting of a master phase (where the major part of the water is absorbed), which is homogeneous and nonpolar (phase 1), and of a second phase with different density and/or hydrophilic character (phase 2). By making the assumption that water diffusion can take place independently in the different phases of the material in accordance with Fick's second law, we can calculate the diffusion coefficient D and the water content at saturation M∞ for each phase separately. Equilibrium water sorption measurements were performed at 40°C, and the data were analyzed and discussed based on the Guggenheim–Anderson–de Boer (GAB) equation, the results being in support of the two‐phase model used in the analysis of absorption kinetics. The linear expansion coefficient and the glass transition temperature of the materials, employed in the discussion of the results, were measured by thermomechanical analysis. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 1165–1182, 1999

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AbstactThe low temperature relaxation mechanisms of epoxy networks and blends were investigated by thermally stimulated discharge current (TSDC) techniques in the temperature range of 77 to 300 K. Two series of specimens, based on DGEBA cured with either TETA or DDM, were prepared. Specimens in the first series were mixed with different amounts of plasticizer Thiocol. The influence of the absorbed water on the low temperature relaxations, and its plasticizing capability were studied, both affected by the presence of plasticizer and water in the specimens. In the second series, blends of CTBN with Epoxy Resin ER were prepared. Four dispersions are observed and ascribed to the CTBN phase, the ER phase and their interfaces.