Abstract
Biodegradable plastics, such as poly(lactic acid) (PLA), are considered the alternative for alleviating the environmental issues caused by the accumulation of petroleum-based plastic wastes. However, PLA is relatively expensive, and its natural degradation is slow. Therefore, upcycling instead of disposing of PLA should be more favorable for sustainability. Herein, we studied the selective methanolysis of PLA to produce methyl lactate (ML) catalyzed by a new molecular catalyst, tetramethylammonium fluoride (TMAF), with superior thermal and chemical stability and excellent catalytic performance. The complete methanolytic depolymerization of the commercial PLA pellets, 4043D, 6060D, 6202D, and 2500HP, was achieved within a short reaction time (<60 mins) under mild conditions (90 °C–110 °C), yielding nearly 100% ML. The reusability of TMAF in the depolymerization of PLA pellets was subsequently investigated. The characterizations by gel permeation chromatography (GPC) and Nuclear Magnetic Resonance (NMR) spectrometry were used to investigate the mechanism of the PLA depolymerization in the methanol solvent. F- was found to be the active center of the TMAF catalyst. A possible random scission depolymerization pathway of the TMAF catalyzed methanolysis of PLA was proposed.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.