IMPEDANCE SPECTROSCOPY OF REACTIVE POLYMERS .1.

Dielectric measurements were utilized to follow the advancement of cur e in an epoxy/amine formulation. In contrast to earlier studies, compl ex impedance was measured during cure and used to calculate ionic resi stivity. By using complex impedance we were able to separate according to their frequency dependence the contributions to overall polarizati on from electrode blocking layers, migrating charges, and dipole relax ations. At any stage of cure, there is a unique frequency at which ion ic resistivity can be singularly measured. Our approach does not invol ve trial-and-error frequency search and is conducive to the developmen t of phenomenological models based on equivalent circuits. Excellent a greement was reported between the calculated values of normalized degr ee of cure obtained by dielectric and calorimetric measurements. (C) 1 994 John Wiley and Sons, Inc.