Abstract
In this study, the author investigated the validity of the radical transfer mechanism for thermal degradation of polymers based on experimental facts and macroscopic considerations. There are various insufficiencies in the radical transfer mechanism which cannot provide any mechanistic explanation, such as the existence of gas-liquid interface in the chemical reaction dominant field, the effect of pressure on the thermal degradation behavior of polymers, and the temperature drop from liquid to gas phase in the reactor.
These insufficiencies indicate that the radical transfer mechanism alone cannot explain the entire process of the thermal degradation of polymers. The generation of volatile products requires a different mechanism than the radical transfer. The author proposed a hydrogen transfer mechanism for breaking the chain-end that produces the volatile, and discussed its consistency with the observed facts.

Keywords
Thermal degradation; Polymer; Radical transfer mechanism; Hydrogen transfer mechanism; Macroscopic mechanism; Insufficiency

Cite this paper
Katsuhide Murata, Mechanistic consideration for the thermal degradation of polymers based on continuous flow operation, SCIREA Journal of Energy. Vol. 7 , No. 2 , 2022 , pp. 17 - 51 . https://doi.org/10.54647/energy48159

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