BUILDUP OF THERMOSET AND CRYSTALLIZATION OF THERMOPLASTICS STUDIED BYELECTRICAL TECHNIQUES

Up to now, few techniques were available that allowed nondestructive i n situ characterization of polymerization during the curing of a therm oset resin. Dynamic dielectric measurements made over a wide range of frequencies provide a sensitive and convenient control to follow up th e epoxy-amine cure or to follow the formation of the thermoplastic mat erials. The direct current measurements and the time of flight measure ments were developed to confirm interpretation of the electrical techn iques in terms of correlations of the evolution of the conductivity an d the network formation and also to evaluate the real value of the ion mobility and its evolution in a course of reaction. (C) 1997 John Wil ey & Sons, Inc.