Towards high-performance sustainable polymers via isomerization-driven irreversible ring-opening polymerization of five-membered thionolactones

• Published in: Nature chemistry Vol. 14; no. 3; pp. 294 - 303
• Main Authors: Yuan, Pengjun, Sun, Yangyang, Xu, Xiaowei, Luo, Yi, Hong, Miao
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.03.2022; Nature Publishing Group
• Subjects: 639/638/224/685; 639/638/455/941; Analytical Chemistry; Biochemistry; Biomass; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Competitive materials; Conversion; Degradability; Inorganic Chemistry; Isomerism; Isomerization; Lactones; Low density polyethylenes; Material properties; Mechanical properties; Organic Chemistry; Petroleum; Physical Chemistry; Polymerization; Polymers; Renewable resources; Ring opening polymerization; Strategy; Sustainability; Sustainable development; Sustainable yield; Thermodynamic properties; Thiolactone
• ISSN: 1755-4330; 1755-4349
• DOI: 10.1038/s41557-021-00817-9

The development of sustainable polymers that possess useful material properties competitive with existing petroleum-derived polymers is a crucial goal but remains a formidable challenge for polymer science. Here we demonstrate that irreversible ring-opening polymerization (IROP) of biomass-derived five-membered thionolactones is an effective and robust strategy for the polymerization of non-strained five-membered rings—these polymerizations are commonly thermodynamically forbidden under ambient conditions, at industrially relevant temperatures of 80–100 °C. Computational studies reveal that the selective IROP of these thionolactones is thermodynamically driven by S/O isomerization during the ring-opening process. IROP of γ-thionobutyrolactone, a representative non-strained thionolactone, affords a sustainable polymer from renewable resources that possesses external-stimuli-triggered degradability. This poly(thiolactone) also exhibits high performance, with its key thermal and mechanical properties comparing well to those of commercial petroleum-based low-density polyethylene. This IROP strategy will enable conversion of five-membered lactones, generally unachievable by other polymerization methods, into sustainable polymers with a range of potential applications. Five-membered lactones are common in nature and are produced in large quantities from biomass, but a lack of ring strain means that ring-opening polymerization is usually thermodynamically unfavourable at ambient conditions. Now, an irreversible ring-opening polymerization of biomass-derived five-membered thionolactones—driven by S/O isomerization—has been developed, enabling their conversion into sustainable polymers at industrially relevant temperatures.