Pyrolysis behaviors of polyethylene terephthalate (PET): A density functional study

In this paper, the pyrolysis mechanism of polyethylene terephthalate (PET), which accounts for a large proportion in plastics component, is investigated by density functional theory (DFT). The dissociation energies of the several important bonds in PET are calculated. The results indicate that the C-C bond between two carboxyl groups in ethylene terephthalate is very weak, followed by the single bond between carboxyl group and carbon atom. The kinetic analysis shows the energy barriers of the reactions to release CO2 are stable while that of CO fluctuates. In addition, the reaction paths of the formation of cyclic compounds are proposed.

Automated summary

This study investigates the pyrolysis mechanism of PET using DFT, revealing that the C-C bond between two carboxyl groups and the single bond between carboxyl group and carbon atom are the weakest in PET. The energy barriers for releasing CO2 are stable, while those for CO fluctuate. Proposed reaction paths for the formation of cyclic compounds are also discussed.