Modeling of Reversible Deactivation Radical Polymerization of Vinyl Monomers Promoted by Redox Initiation Using NHPI and Xanthone

Abstract

AbstractTwo mathematical approaches for modeling of the kinetics and evolution of molar mass distributions in the reversible deactivation radical polymerization of vinyl monomers promoted by redox reaction with N‐hydroxyphthalimide (NHPI) and xanthone (XT) are presented. In the first modeling approach, the polymerization scheme is implemented in the standard version of the Predici commercial software. In the second case, an accelerated, self‐implemented version of the so called kinetic Monte Carlo (kMC) approach, considering binary trees, is used. The effect of concentrations of XT and monomer, as well as monomer type, on monomer conversion, NHPI efficiency, molar mass averages, molar mass dispersity, and full molar mass distributions are studied. The models are validated using literature available experimental data of polymerizations of methyl methacrylate (MMA) and styrene, in toluene, at 70 °C. The calculated results indicate that NHPI initiator efficiencies are low (<0.2); polymer end‐group functionalities present a maximum value of about 0.8 with a subsequent decrease with monomer conversion; molar mass distributions are broad, exhibiting low molar mass tails. In addition, the hypothetical copolymerization of styrene and MMA is also considered. Copolymer composition distributions for short molecules are broader than those for large ones.