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Facile Preparation of Stereoblock PLA From Ring-Opening Polymerization of rac-Lactide by a Synergetic Binary Catalytic System Containing Ureas and Alkoxides.

ABSTRACT: Ring-opening polymerization (ROP) of cyclic esters/lactones by efficient catalysts is a powerful method for synthesis of biodegradable and biocompatible polyesters with well-defined structures. To develop catalytic systems that are fast, selective and controlled is a persistent effort of chemists. In this contribution, we report a binary urea/alkoxide catalytic system that could catalyze ROP of rac-LA in a fast (over 90% conversion within 1-2 min), stereoselective (P _i up to 0.93) and controlled manner, indicated by narrow MW distributions, linear relationship between the monomer conversions and M _ns, end-group fidelity, and chain extension experiments. Remarkably, the catalytic system described here is simple, easily prepared, and structurally tunable and thus has versatile catalytic performances.

SUBMITTER: Kan Z

PROVIDER: S-EPMC6240762 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Facile Preparation of Stereoblock PLA From Ring-Opening Polymerization of rac-Lactide by a Synergetic Binary Catalytic System Containing Ureas and Alkoxides.

Kan Ze Z Luo Wenlong W Shi Tong T Wei Chuanzhi C Han Binghao B Zheng Dejuan D Liu Shaofeng S

Frontiers in chemistry 20181109

Ring-opening polymerization (ROP) of cyclic esters/lactones by efficient catalysts is a powerful method for synthesis of biodegradable and biocompatible polyesters with well-defined structures. To develop catalytic systems that are fast, selective and controlled is a persistent effort of chemists. In this contribution, we report a binary urea/alkoxide catalytic system that could catalyze ROP of rac-LA in a fast (over 90% conversion within 1-2 min), stereoselective (P i u ...[more]

PMID: 30483495

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