Chinese Journal of Polymer Science

, Volume 36, Issue 2, pp 231–236 | Cite as

Stereoselective ring-opening polymerization of rac-lactide by bulky chiral and achiral N-heterocyclic carbenes

  • Hui Li
  • Bai-Ru Ai
  • Miao HongEmail author


Despite the extraordinary success has been achieved in metal catalyst-promoted stereoselective ring-opening polymerization (ROP) of rac-lactide (rac-LA), well-controlled stereoselective rac-LA ROP by organic catalyst still remains a scientific challenge. Here we report our investigations into organocatalytic stereoselective ROP of rac-LA by utilizing novel bulky chiral and achiral N-heterocyclic carbenes (NHC), 1,3-bis-(1′-naphthylethyl)imidazolin-2-ylidene. The effect of polymerization conditions (e.g. solvent, temperature, alcohol initiator) on ROP behavior by these bulky NHCs has been fully studied, leading to the formation of isotactic-rich stereoblock polylactide (Pi = 0.81) under optimized conditions with high activity (Conv. = 98% in 30 min) and narrow molecular weight dispersity (Ɖ = 1.05).


Polylactide Ring-opening polymerization Stereoselectivity Organic catalyst N-heterocyclic carbene 


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This work was financially supported by the Science and Technology Commission of Shanghai Municipality (No. 17JC1401200).


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Copyright information

© Chinese Chemical Society, Institute of Chemistry, Chinese Academy of Sciences and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Key Laboratory of Marine Materials and Related Technologies, Key Laboratory of Marine Materials and Protective Technologies of Zhejiang Province, Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingboChina
  2. 2.University of Chinese Academy of SciencesBeijingChina
  3. 3.State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghaiChina

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