CHEMILUMINESCENCE OF DIGLYCIDYL ETHER OF BISPHENOL-A - NORBORNENE ANHYDRIDE NETWORKS

Networks were prepared by curing diglycidyl ether of bisphenol A (DGEB A) with variable concentrations of norbornene anhydride (NA). Almost c ompletely cured samples with anhydride/epoxide (A/E) molar ratios of r espectively 0.8, 0.9, 1.0 and 1.1, and one incompletely cured sample w ith A/E = 1.0, were studied by chemiluminescence in the temperature ra nge 135-220-degrees-C, using isothermal stationary or non-stationary ( atmosphere change) exposures. The comparison of kinetic curves of inte nsity variation reveals: the importance of unreacted epoxide groups as sources of highly emissive radical species, the lowering effect of ox idation products, and the increasing effect of the decrease of macromo lecular mobility due to crosslinking in the case of the incompletely c ured sample. Most of the features of kinetic curves obtained in non-st ationary experiments are explained in terms of radical formation mecha nisms during exposure in inert atmosphere. The results show clearly th at chemiluminescence is due to reactions of peroxy radicals rather tha n hydroperoxide groups.