Kinetics and Reaction Mechanism of the Oxidative Polymerization of 2, 6-Xylenolt

Abstract

The elementary reactions and the rate-determining step were proposed on the basis of experimental results of oxidative polymerization of 2, 6-xylenol with the catalyst composed of manganese chloride, 2-aminoethanol, and methanol.
The rate-determining step was speculated to be in the process of formation of quinone acetal intermediate (Eq.10). The oxidation of the manganese complex with oxygen, the coordination of phynoxide ion to manganese, the one-electron oxidation, the redistribution reaction of the quinone acetal, and the re-oxidation of the manganese complex catalyst were all regarded to be sufficiently rapid. Furthermore the redistribution reaction was assumed to proceed under the desirable control within coordination sphere of the manganese complex catalyst.
The eq uations drived on the above-mentioned assumption to account for the relationships such as the extent of reaction (p) vs the reaction time, p vs the residual monomer, p vs the polymer yield, and p vs the molecular-weight distribution were shown to be in good accordance with the experimental results (Figs.1 to 4) enough to support the validity of the proposed kinetics and reaction mechanism.