Polymer Tacticity Control for Stereoselective Ring-Opening Polymerization of Racemic n‑Propylglycolide

• Published in: ACS catalysis Vol. 14; no. 2; pp. 1173 - 1182
• Main Authors: Li, Guojie, Xu, Guangqiang, Guo, Xuanhua, Yang, Rulin, Sun, Hongguang, Wang, Qinggang
• Format: Journal Article
• Language: English
• Published: American Chemical Society 19.01.2024
• Subjects: CEC mechanism; n-propylglycolide; ESC mechanism; tacticity; polyester; stereoselective ring-opening polymerization
• ISSN: 2155-5435; 2155-5435
• DOI: 10.1021/acscatal.3c04798

The synthesis of stereoregular aliphatic polyesters with superior (bio)­degradability and recyclability has been one of the promising areas in material science, which can be achieved through the stereoselective polymerization of cyclic esters. However, it remains a long-standing challenge to achieve tacticity (isotactic and heterotactic) control of aliphatic polyesters in one catalytic system through modulation of the polymerization mechanism. Here we reported a tunable and controllable method for stereoselective polymerization of racemic n-propylglycolide ( n Prgl) based on the analysis of the enantiomorphic site control (ESC) and chain-end control (CEC) mechanisms in the polymerization. The enantiomorphic site control and chain-end control-dominated stereoregular polymerization processes were achieved via adjustable polymerization conditions, producing isotactic poly­( n Prgl) with a P m of up to 0.88 (based on ESC) and heterotactic poly­( n Prgl) with a P r of up to 0.94 (based on CEC). This understanding of ESC and CEC mechanisms might provide a compelling guidance to the design of stereoselective polymerization.