Steady State and Equilibrium in Reversible Copolymerization at Constant Comonomer Concentrations

Abstract

Selected aspects of copolymerization processes carried on at constant comonomer concentrations are analyzed theoretically and modeled by Monte Carlo method. It is confirmed that some combinations of initial parameters lead to stationary conditions of copolymer formation for both irreversible and reversible systems which can be regarded as the first‐order Markov chain process. However, this study shows that for many copolymerization systems the stationary conditions are attained only at high number‐average degree of polymerization DPn, and for some reversible copolymerizations, attaining equilibrium, stationary conditions are not observed at all. The analysis shows that the chain length distribution (CLD) for copolymerization carried out under steady state conditions at constant comonomer concentrations, equal to equilibrium concentrations for infinitely high DPn, is approximately described by the modified Bessel and exponential functions. This type of CLD is analytically proved and confirmed by the Monte Carlo simulations for the analogous homopolymerization process.

Evolution of Chain Length Distribution and Microstructure of Macromolecules in Irreversible Copolymerization Proceeding with Segmental Exchange Investigated with a New Monte Carlo Algorithm

“…Role of depropagation in copolymerization processes has been described in our earlier papers. [41,42] A pronounced effect of depropagation on evolution of copolymer microstructure and equilibrium conditions, as well on equilibration time, has been discussed in details in these papers.…”