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Polymers of ?-Caprolactone Using New Copper(II) and Zinc(II) Complexes as Initiators: Synthesis, Characterization and X-Ray Crystal Structures.

ABSTRACT: Five of six new Zn(II) and Cu(II) complexes were active in the ring-opening polymerization (ROP) of ?-caprolactone (CL) under solvent-free conditions, producing polycaprolactones (PCLs) of high crystallinity with molecular weights between 22,900 and 38,700 g mol^-1 and decomposition temperatures above 260 °C. ¹H NMR analysis demonstrated that the PCLs obtained were mainly linear, having hydroxymethylene groups at the chain ends. The results obtained indicated a significant improvement in terms of the ratio of monomer:initiator compared to related Cu(II) and Zn(II) complexes. In addition, the structures of the complexes 1 and 4 were determined by single-crystal X-ray diffraction. The synthesis and full characterization of all complexes are described in this paper.

SUBMITTER: Posada AF

PROVIDER: S-EPMC6401771 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Polymers of ε-Caprolactone Using New Copper(II) and Zinc(II) Complexes as Initiators: Synthesis, Characterization and X-Ray Crystal Structures.

Posada Andrés F AF Macías Mario A MA Movilla Santiago S Miscione Gian Pietro GP Pérez León D LD Hurtado John J JJ

Polymers 20181108 11

Five of six new Zn(II) and Cu(II) complexes were active in the ring-opening polymerization (ROP) of ε-caprolactone (CL) under solvent-free conditions, producing polycaprolactones (PCLs) of high crystallinity with molecular weights between 22,900 and 38,700 g mol<sup>-1</sup> and decomposition temperatures above 260 °C. ¹H NMR analysis demonstrated that the PCLs obtained were mainly linear, having hydroxymethylene groups at the chain ends. The results obtained indicated a significant improvement ...[more]

PMID: 30961164

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Dataset Information

Polymers of ?-Caprolactone Using New Copper(II) and Zinc(II) Complexes as Initiators: Synthesis, Characterization and X-Ray Crystal Structures.

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Polymers of ε-Caprolactone Using New Copper(II) and Zinc(II) Complexes as Initiators: Synthesis, Characterization and X-Ray Crystal Structures.

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