Modeling of Isoprene Solution Coordinative Chain Transfer Polymerization

Abstract

AbstractThe present manuscript investigates the solution coordinative chain transfer polymerization (CCTP) of isoprene initiated by the ternary Ziegler‐Natta catalyst system composed by neodymium versatate (), diisobutylaluminum (DIBAH), and dimethyldichlorosilane. A kinetic mechanism is proposed and the kinetic parameters are estimated to allow the appropriate description of dynamic trajectories of average molecular weights and isoprene conversions obtained in solution CCTP polymerizations for the first time. A data reconciliation strategy is applied to evaluate the amount of DIBAH used as a chain transfer agent, as this very active compound can be consumed by undesired side reactions. Additionally, the impacts of key operation variables on the control of the average molecular weights and monomer conversion are evaluated to elucidate the living nature of the polymerization. As observed experimentally, the temperature effect on the course of the polymerization is not so pronounced as the effect of , isoprene, and DIBAH initial concentrations. The kinetic mechanism is described better and kinetic constants are estimated more precisely when the dynamic trajectories of average molecular weights are fitted during the whole batch. In this case, the proposed model is able to predict well the experimental trajectories of average molecular weights of the produced polymer and monomer conversion.