Chinese Journal of Polymer Science

, Volume 37, Issue 3, pp 258–267 | Cite as

Influence of Chain Architectures on Crystallization Behaviors of PLLA Block in PEG/PLLA Block Copolymers

  • Sheng Xiang
  • Dong-Dong Zhou
  • Li-Dong Feng
  • Xin-Chao Bian
  • Gao LiEmail author
  • Xue-Si ChenEmail author
  • Tian-Chang Wang


The effect of the architecture of poly(ethylene glycol)/poly(L-lactide) (PEG/PLLA) block copolymers on the non-isothermal crystallization behaviors of PLLA blocks was investigated by differential scanning calorimetry (DSC) and wide angle X-ray diffraction (WAXD). 1-Arm MPEG-b-PLLA and 4-arm PEG-b-PLLA (4PEG-b-PLLA) were synthesized by the ring-opening polymerization of Llactide in the presence of poly(ethylene glycol) methyl ether (MPEG) and 4-arm poly(ethylene glycol) (4PEG). 4-Arm PLLA-b-MPEG (4PLLA-b-PEG) was synthesized by coupling 4-arm PLLA and MPEG. The WAXD results indicated that the crystalline structure of PLLA blocks did not alter due to the different chain architectures. The average values of Avrami index (\(\bar{n}\)) were all above 4, which indicated that the nucleation mechanism of PLLA blocks was heterogeneous nucleation, regardless of the architectures. The overall crystallization rates were decreased markedly as following: MPEG-b-PLLA > 4PEG-b-PLLA > 4PLLA-b-PEG, ascribed to the different confinement by PEG blocks and to the steric hindrance of chain architectures. Therefore, the crystallization of PLLA blocks became more difficult and the crystallization activation energy of the PLLA blocks increased due to the confinement of chain architectures.


Poly(L-lactide) Poly(ethylene glycol)/poly(L-lactide) block copolymer Non-isothermal crystallization Chain architecture 


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This work was financially supported by the National Natural Science Foundation of China (Nos. 51303176, 51873209, 51573178, and 51773194) and the National Key Research and Development Program of China (No. 2016YFB0302500).

Supplementary material

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Influence of Chain Architectures on Crystallization behaviors of PLLA block in PEG/PLLA block copolymers


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Copyright information

© Chinese Chemical Society, Institute of Chemistry (CAS) and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Sheng Xiang
    • 1
    • 2
    • 3
  • Dong-Dong Zhou
    • 4
  • Li-Dong Feng
    • 1
    • 2
  • Xin-Chao Bian
    • 1
    • 2
  • Gao Li
    • 1
    • 2
    Email author
  • Xue-Si Chen
    • 1
    • 2
    Email author
  • Tian-Chang Wang
    • 1
    • 2
  1. 1.Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchunChina
  2. 2.Jilin Biomedical Polymers Engineering LaboratoryChangchunChina
  3. 3.University of Chinese Academy of SciencesBeijingChina
  4. 4.South China Advanced Institute for Soft Matter Science and TechnologySouth China University of TechnologyGuangzhouChina

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