Effect of intramolecular reactions in multifunctional step growth polymerizations in cascades of continuous-flow,stirred-tank reactors

A simple kinetic model describing intramolecular reactions in multifunctional step growth polymerizations of RA_j monomers is presented. The model is far simpler than more detailed kinetic or Monte Carlo models which pose severe numerical difficulties close to gelation. The formulation presented is quite general, but it requires a relationship for the ensemble-cum-time average number of rings, r _n, per molecule having n RA_j units. A very simple yet intuitively correct equation has been chosen for r _n, which involves an empirical parameter ?? Results on cascades of homogeneous continuous-flow stirred-tank reactors (HCSTRs) show trends which are physically expected. The present formulation could possibly be used for scale-up of HCSTRs, with ?? obtained experimentally. It is hoped that future studies using rigorous models would lead to more fundamental and improved relationships for r _n.