Copolymerization between A3 and B2 with ring formation and different intrinsic reactivity in one of the monomers

Abstract

We present two models for the stepwise copolymerization between a three-functional monomer As and a bifunctional monomer B2 where both intramolecular reaction and different intrinsic reactivities of reactive sites are present. The difference in reactivities may be either on the A sites or the B sites, leading to two different models. The models may calculate both pregel and postgel parameters. One of the two models presents a nonsymmetrical response to the rate constant ratio. Each of the nonidealities was previously known to lead to a delay in gel point when considered individually; we find in this work that when present simultaneously they may either reinforce or compensate each other, depending on the reacting conditions. We reinterpret some experimental data from the literature using one of the models, with satisfactory results.