Oscillatory Carbonylation of Poly(Ethylene Glycol)Methyl Ether Acetylene. Modelling of Reaction Mechanism and Stoichiometric Network Stability Analysis

The reaction mechanism of palladium-catalysed oscillatory carbonylation of poly(ethylene glycol)methyl ether acetylene (PEGA) was examined by stoichiometric network analysis (SNA) of the stability of the dynamic states. The previously published simplified reaction network proposed to account for the experimentally observed results was modified in order to obtain a more realistic reaction network for the investigated process. In the modified reaction network, the direct autocatalytic steps were replaced with autocatalytic loops. In this procedure some complex net reactions had to be resolved, while some new reactions had to be taken into account, altering the reaction mechanism responsible for the appearance of oscillation. Moreover, in the modified reaction network, the expressions for reaction rates correspond formally to their stoichiometry in accordance to mass action kinetics. The SNA identified the instability condition which was further tested and confirmed by numerical simulation.