I. M. Kalogeras (a), M. Roussos (a), I. Christakis (a), A. Spanoudaki (b), D. Pietkiewitcz (c), W. Brostow (c) and A. Vassilikou-Dova (a).
(a) Department of Physics, Solid State Physics Sections, University of Athenas, Panepistimiopolis, 157 84 Zografos, Greece
(b) Department of Physics, National Technical University of thenas, Zografou Campus, 157 80 Athens, Greece
(c) LAPOM, Department of Materials Science and Engineering, University of North Texas, PO Box 305310, Denton, TX, USA
ABSTRACT
Epoxy resin (ER) + poly(ethylene oxide) (PEO) blends cured with 4,4'-diaminodiphenyl-methane were studied by thermally stimulated currents and dielectric relaxation spectroscopy. Tbe results confirm components miscibility with dielectric glass transition temperature-composition dependence obeying the empirical Gordon-Taylor G- T equation with k = 0.38. Positive departures from the G-T curve appear at high PEO loadings due to crystallization of the linear polyether. Subtle perturbations of the local-chain relaxation dynamics and the relatively low k estimate advocate for weakened intermolecular-specific interactions in the miscible blends, compared with the intramolecular self-association of hydroxyls in pure ER, suggesting structural similarity as the primary driving force for phase miscibility.