Related Experiment Video
Updated: May 14, 2025
07:28
Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
Published on: November 27, 2015
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Modeling the Kinetics of Polyethylene Terephthalate and Polyesters with Terminal Hydroxyl Groups Transesterification
Kirill A Kirshanov1, Roman V Toms1, Gadir Sh Aliev1
1M.V. Lomonosov Institute of Fine Chemical Technologies, MIREA-Russian Technological University, 119571 Moscow, Russia.
Polymers
|April 12, 2025
Summary
This study introduces a kinetic model for interchain exchange in polyethylene terephthalate (PET) recycling via transesterification. The model accurately predicts product composition and molecular weight, improving chemical recycling efficiency.
Area of Science:
- Polymer Chemistry
- Chemical Engineering
- Materials Science
Background:
- Classical chemical recycling of polyethylene terephthalate (PET) involves molecular weight reduction and polycondensation.
- Interchain exchange via transesterification offers a direct route to PET-based polyester products, bypassing traditional steps.
Purpose of the Study:
- To develop and validate a kinetic model for interchain exchange reactions in PET.
- To describe the concentration changes of various monomers and oligomers during transesterification.
- To investigate the molecular weight characteristics of recycled polyester products.
Main Methods:
- Development of a novel kinetic model for transesterification-driven interchain exchange.
- Experimental determination of randomness and conversion over time for PET/oligodiethylene terephthalate mixtures.
- Analysis of molecular weight characteristics of interchain exchange products.
- Comparison of simulation results with experimental data and published findings for PET/PEN blends.
Main Results:
- The kinetic model accurately describes the changes in bound and terminal unit concentrations during transesterification.
- Experimental data on randomness and conversion align with the model's predictions.
- Molecular weight characteristics of recycled products were successfully investigated.
- Model simulations showed good agreement with experimental data and published results for related systems.
Conclusions:
- The developed kinetic model provides a robust framework for understanding and optimizing PET interchain exchange.
- This approach enables efficient chemical recycling of PET without molecular weight reduction steps.
- The model is validated by experimental data and its applicability is demonstrated for PET/PEN blends.
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