文献类型：期刊文献

英文题名：Ring-opening polymerization of lactide, ε-caprolactone and their copolymerization catalyzed by β-diketiminate zinc complexes

作者：Keram, Maryam;Ma, Haiyan[1,2]

机构：[1]East China Univ Sci & Technol, Shanghai Key Lab Funct Mat Chem, Sch Chem & Mol Engn, 130 Meilong Rd, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Lab Organometall Chem, Sch Chem & Mol Engn, 130 Meilong Rd, Shanghai 200237, Peoples R China

年份：2017

卷号：31

期号：12

外文期刊名：APPLIED ORGANOMETALLIC CHEMISTRY

收录：;EI(收录号：20172303744215);WOS:【SCI-EXPANDED(收录号:WOS:000419195800076)】；

基金：National Natural Science Foundation of China, Grant/Award Number: 21074032 and 21474028; Fundamental Research Funds for the Central Universities, Grant/Award Number: WD1113011

语种：英文

外文关键词：copolymerization; lactide; ring-opening polymerization; zinc complex; epsilon-caprolactone

摘要：A series of zinc silylamido complexes bearing non-symmetric beta-diketiminate ligands were synthesized and structurally characterized. Ring-opening polymerization (ROP) of rac-lactide catalyzed by these zinc complexes afforded heterotactic polylactides at room temperature (P-r = 0.79 similar to 0.83 in THF). The steric and electronic characteristics of the ancillary ligands showed significant influence on the polymerization performance of the corresponding zinc complexes. All these zinc complexes also showed moderate activities toward the polymerization of epsilon-caprolactone at ambient temperature in toluene, producing polycaprolactones (PCLs) with high molecular weights and moderate polydispersities. PCL-b-PLLA copolymers could be obtained via three different copolymerization strategies (one-pot polymerization, and sequential addition of the two monomers in either order) by adopting complex 6 as the initiator through the adjustment of reaction temperatures. The diblock nature of the copolymers was confirmed by C-13 NMR spectroscopy and DSC analysis.