Comprehensive Report
Coordination Insertion Mechanism of Ring-Opening Polymerization of Lactide Catalyzed by Stannous Octoate†
Weihan Rao,
Caiyun Cai,
Jingyu Tang,
Yiman Wei,
Caiyun Gao,
Lin Yu,
Jiandong Ding,
Weihan Rao
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438 China
Search for more papers by this authorCaiyun Cai
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438 China
Search for more papers by this authorJingyu Tang
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438 China
Search for more papers by this authorYiman Wei
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438 China
Search for more papers by this authorCaiyun Gao
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438 China
Search for more papers by this authorLin Yu
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438 China
Zhuhai Fudan Innovation Institute, Zhuhai, Guangdong, 519000 China
Search for more papers by this authorCorresponding Author
Jiandong Ding
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438 China
Zhuhai Fudan Innovation Institute, Zhuhai, Guangdong, 519000 China
E-mail: [email protected]Search for more papers by this authorWeihan Rao,
Caiyun Cai,
Jingyu Tang,
Yiman Wei,
Caiyun Gao,
Lin Yu,
Jiandong Ding,
Weihan Rao
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438 China
Search for more papers by this authorCaiyun Cai
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438 China
Search for more papers by this authorJingyu Tang
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438 China
Search for more papers by this authorYiman Wei
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438 China
Search for more papers by this authorCaiyun Gao
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438 China
Search for more papers by this authorLin Yu
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438 China
Zhuhai Fudan Innovation Institute, Zhuhai, Guangdong, 519000 China
Search for more papers by this authorCorresponding Author
Jiandong Ding
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, 200438 China
Zhuhai Fudan Innovation Institute, Zhuhai, Guangdong, 519000 China
E-mail: [email protected]Search for more papers by this author† In Memory of Professor Lina Zhang.
Main observation and conclusion
Ring-opening polymerization (ROP) of cyclic esters in the presence of stannous octoate (Sn(Oct)2) is the main way to obtain biodegradable aliphatic polyesters, an important family of biodegradable polymers which have been widely used and still rapidly developed in the fields of biomedical polymers and environment-friendly materials. The underlying mechanism is thought via a coordination-insertion way, but the pathway is still open owing to the absence of direct experimental evidence. Herein, we inquire this issue through density functional theory (DFT) calculations. According to our DFT calculations and the following Curtin-Hammett evaluation, the carbonyl oxygen has a significant advantage over the ester oxygen, and thus the ring is opened mainly through pathway A instead of pathway B. The stannous octoate is identified as a catalyst rather than an initiator. We eventually summarize the main stages during the whole polymerization of lactide.
Supporting Information
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Appendix S1: Supporting Information |
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