Perturbation of the oscillatory BZ reaction with methanol and ethylene glycol: Experiments and model calculations

摘要: This study is initiated by a recent discovery, according to which water soluble polymer, poly(ethylene glycol) (PEG), affects the dynamics of Belousov-Zhabotinsky (BZ) reaction in characteristic way. As various polymers and polymer-based hydrogels are often applied nonlinear chemical experiments, it an interesting question whether effect polymer can be attributed exclusively its reactive endgroups (here primary alcoholic groups) or if macromolecular nature perturbant might also important. In this paper, as first step, results batch experiments presented applying only small molecules, namely ethylene glycol (the monomer PEG) methanol (a more simple alcohol), perturbants BZ reaction. The was followed monitoring rate carbon dioxide evolution. experimental compared with model calculations, latest reaction, Marburg-Budapest-Missoula (MBM) mechanism extended perturbing reactions. reactions (reaction acidic bromate alcohol producing autocatalytic intermediate bromous acid) determined separate spectrophotometric experiments. Experiments calculations show good qualitative agreement (alcoholic perturbations increase induction period frequency oscillations decrease amplitude), but disagreements were found on quantitative level. Because perturbation, especially case methanol, mostly clarified, MBM should modified somewhat future. responds rather sensitively, simulating these perturbation help test new mechanistic proposals for