Data_Sheet_1_Facile Preparation of Stereoblock PLA From Ring-Opening Polymerization of rac-Lactide by a Synergetic Binary Catalytic System Containing Ureas and Alkoxides.docx

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 (Pi up to 0.93) and controlled manner, indicated by narrow MW distributions, linear relationship between the monomer conversions and Mns, 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.

通过高效催化剂催化环状酯/内酯的开环聚合（Ring-opening polymerization, ROP），是合成结构明确、可生物降解且生物相容聚酯的高效手段。长期以来，开发快速、选择性优异且可控的催化体系始终是化学家们的不懈追求。在本研究工作中，我们报道了一种双组分脲/醇盐催化体系，该体系可催化外消旋丙交酯（rac-LA）的开环聚合，展现出快速（1~2分钟内单体转化率超90%）、立体选择性突出（立构选择性参数Pi最高可达0.93）且可控的催化特性，该特性可通过窄分子量分布、单体转化率与数均分子量（Mns）间的线性关系、端基保真度以及扩链实验得到验证。值得注意的是，本文所报道的催化体系制备简便、结构可调且简洁易用，因此具备多样化的催化性能。