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Updated: May 24, 2026

Synthesis of Monodisperse Cylindrical Nanoparticles via Crystallization-driven Self-assembly of Biodegradable Block Copolymers
Published on: June 20, 2019
Direct cyclodextrin-mediated ring opening polymerization of ϵ-caprolactone in the presence of yttrium trisphenolate
Xin Li1, Yinghong Zhu, Jun Ling
1MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China.
Abstract:
Unmodified β-cyclodextrin has been directly used to initiate ring-opening polymerization of ϵ-caprolactone in the presence of yttrium trisphenolate. Well-defined cyclodextrin (CD)-centered star-shaped poly(ϵ-caprolactone)s have been successfully synthesized containing definite average numbers of arms (N(arm) = 4-6) and narrow polydispersity indexes (below 1.10). The number-average molecular weight (M(n,NMR)) and average molecular weight per arm (M(n,arm)) are controlled by the feeding molar ratio of monomer to initiator. The prepared star-PCL with M(n,NMR) of 2.7 × 10(3) is in fully amorphous and that with M(n,NMR) of 13.3 × 10(3) is crystallized. In addition, the obtained poly(e-caprolactone) (PCL) stars with various molecular weights have different solubilities in methanol and tetrahydrofuran, which can be applied for further modifications.
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