Thermal degradation and upcycling of Stereoregular polyesters

• Published in: Reactive & functional polymers 2023-12, Vol.193, p.105756, Article 105756
• Main Authors: Ding, Huining, Wu, Xianmin, Guo, Kening, Heo, Ju-Yeong, Duan, Zhongyu, Liu, Binyuan, Kim, Il
• Format: Article
• Language: English
• Subjects: Bulky pentacyclic anhydride; Polyester; Retro-diels-alder reaction; Thermal degradation; Thermal stability; Upcycling
• ISSN: 1381-5148
• DOI: 10.1016/j.reactfunctpolym.2023.105756

In this study, the thermal degradation behavior and the decomposition products obtained during the pyrolysis of a new polyester, poly(HASA/CHO) (PHC), were investigated. Thermogravimetric (TG) and differential thermogravimetric (DTG) analyses indicated that the pyrolysis of PHC could be divided into three stages. The average activation energies for stages I and III were estimated using the Kissinger method. The pyrolytic processes were monitored using gel permeation chromatography (GPC), differential scanning calorimetry (DSC), nuclear magnetic resonance (NMR), and ultraviolet-visible UV–vis spectroscopy. The effects of the PHC configuration on the thermal stability and evolution of the thermal process were explored. The results demonstrated that, compared to the cis-PHC, the trans-PHC is more likely to release anthracene via a retro-Diels-Alder reaction, and exhibits higher main chain stability. Interestingly, PHC could be reversibly recycled via the Diels-Alder reaction, leading to potential upcycling of the copolymer. PHC releases anthracene via the retro-Diels–Alder (DA) reaction and reversibly recycles itself via the Diels–Alder reaction, potentially upcycling of the copolymer. [Display omitted] •Trans-PHC shows a greater tendency to release anthracene than that in cis isomer.•ain-chain stability of cis-PHC is lower than that of trans-PHC.•The retro-DA reaction of the side groups in trans-PHC proceeds with polymer scission.•PHC can be reversibly recycled via the Diels–Alder reaction, resulting in upcycling.