KINETIC-MODEL FOR GELATION IN THE DIEPOXIDE-CYCLIC ANHYDRIDE COPOLYMERIZATION INITIATED BY TERTIARY-AMINES

The best models available in the literature to analyze gelation in the diepoxide-cyclic anhydride copolymerization are based on the mean-fie ld approach. A kinetic model was developed to account for the nonrando m steps of the copolymerization. Two kinetic schemes were employed wit h one including chain transfer steps. Predicted gel-point conversions as a function of the initiator concentration were compared with experi mental results obtained for a system based on diglycidyl ether of bisp henol A, methyltetrahydrophthalic anhydride, and benzyldimethylamine, as initiator. Both kinetic schemes explained the observed first-order kinetics for monomer consumption, after an induction period. However, experimental gel-point conversions could only be fitted by assuming th e presence of a chain transfer step regenerating an active species.