Title |
Thermal Pyrolysis of Polystyrene Aided by a Nitroxide End-Functionality. Experiments and Modeling |
ID_Doc |
10491 |
Authors |
Ordaz-Quintero, A; Monroy-Alonso, A; Saldívar-Guerra, E |
Title |
Thermal Pyrolysis of Polystyrene Aided by a Nitroxide End-Functionality. Experiments and Modeling |
Year |
2020 |
Published |
Processes, 8, 4 |
DOI |
10.3390/pr8040432 |
Abstract |
The thermal pyrolysis of polystyrene (PS) is gaining importance as the social pressure for achieving a circular economy is growing; moreover, the recovery of styrene monomer in such a process is especially relevant. In this study, a simple thermal pyrolysis process in the temperature range of 390-450 degrees C is developed. A working hypothesis is that by using a nitroxide-end functionalized PS (PS-T or dormant polymer), the initiation process for the production of monomer (unzipping) during the PS pyrolysis could be enhanced due to the tendency of the PS-T to activate at the nitroxide end. Two types of PS were used in this work, the first one was synthesized by free-radical polymerization (FRP-dead polymer) and the second by nitroxide-mediated polymerization (NMP) using three levels of nitroxide to initiator ratio: 1.3, 1.1, and 0.9. Analysis of the recovered products of the pyrolysis by gas-mass spectroscopy shows that the yield of styrene increases from similar to 33% in the case of dead polymer to similar to 38.5% for PS-T. A kinetic and mathematical model for the pyrolysis of dead and dormant polymer is proposed and solved by the method of moments. After a parameter sensitivity study and data fitting, the model is capable of explaining the main experimental trends observed. |
Author Keywords |
polystyrene; thermal pyrolysis; nitroxide mediated polymerization; mathematical modeling |
Index Keywords |
Index Keywords |
Document Type |
Other |
Open Access |
Open Access |
Source |
Science Citation Index Expanded (SCI-EXPANDED) |
EID |
WOS:000536891900112 |
WoS Category |
Engineering, Chemical |
Research Area |
Engineering |
PDF |
https://www.mdpi.com/2227-9717/8/4/432/pdf?version=1586351363
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