Chinese Journal of Polymer Science

, Volume 37, Issue 10, pp 990–994 | Cite as

Mechanism of Janus Polymerization: A DFT Study

  • Tian-Wen Bai
  • Xu-Feng Ni
  • Jun LingEmail author
  • Zhi-Quan Shen


Janus polymerization is featured as a combination of cationic and anionic growing ends in one living polymer chain. In the copolymerization of THF and CL catalyzed by lutetium triflates and initiated by propylene oxide, three stages are identified by kinetic study including (1) fast cationic polymerization with slow anionic one, (2) fast anionic polymerization with dormant cationic one, and (3) reactivation of cationic polymerization with coupling of anionic and cationic chain ends. In this work, density functional theory (DFT) calculation is employed to investigate the reaction details of ionic polymerization and dormancy. A “tripedal crow” configuration is proposed to illustrate the unique high-coordinated ligand exchange configuration in anionic polymerization in different stages. The trigger of dormancy is determined as chain structures rather than concentration of triflate anion according to both calculation and experimental results.


Rare earth metal catalysts Ring-opening polymerization Ionic polymerization Reaction mechanism Quantum chemical computation 


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This work was financially supported by the National Natural Science Foundation of China (No. 21871232) and the Zhejiang Provincial Natural Science Foundation of China (No. LR15B040001).

Supplementary material

10118_2019_2318_MOESM1_ESM.pdf (465 kb)
Mechanism of Janus polymerization: A DFT study


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Copyright information

© Chinese Chemical Society Institute of Chemistry, Chinese Academy of Sciences Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • Tian-Wen Bai
    • 1
  • Xu-Feng Ni
    • 1
  • Jun Ling
    • 1
    Email author
  • Zhi-Quan Shen
    • 1
  1. 1.Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and EngineeringZhejiang UniversityHangzhouChina

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