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论文类型：期刊论文

第一作者：Hu, Minggang

通讯作者：Wang, M (reprint author), Dalian Univ Technol, State Key Lab Fine Chem, DUT KTH Joint Educ & Res Ctr Mol Devices, Dalian 116012, Peoples R China.

合写作者：Wang, Mei,Zhang, Peili,Jin, Kun,Chen, Yuee,Sun, Licheng

发表时间：2012-04-01

发表刊物：POLYMER BULLETIN

收录刊物：SCIE、EI、Scopus

卷号：68

期号：7

页面范围：1789-1799

ISSN号：0170-0839

关键字：Hafnium; Isoselectivity; Lactide; Polymerization; Zirconium

摘要：The hydroxyl- and phenoxy-bridged dinuclear zirconium and hafnium complexes, 1 and 2, containing a chiral N atom in the N2O2 ligand (H2L = 2-(((2-pyridylmethyl)(2-hydroxyphenyl)amino)methyl)-4,6-di(tert-butyl)phenol) were used as catalysts for the ring-opening polymerization of rac-lactide. Experiments prove that 1 and 2 are living and controlled catalytic systems with activity up to 3.25 g(pol) mmol(ini) (-1) h(-1). The isotactic-rich polylactides in a narrow polydispersity (M (w)/M (n) = 1.01-1.13) were produced with enantiomeric complexes 1 and 2 (P (m) = 0.65-0.73). The kinetic studies show a first-order dependency in both monomer and initiator. The initiation mechanism is discussed on the basis of the MALDI-TOF MS and H-1 NMR spectra of the rac-LA oligomer prepared by 1.