𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Controlled Ring-Opening Polymerization of e-Caprolactone Catalyzed by a Rare Earth Schiff-Base Complex

✍ Scribed by Xufeng NI; Weiwei ZHU; Zhiquan SHEN

Publisher
Elsevier Science
Year
2010
Weight
458 KB
Volume
31
Category
Article
ISSN
1872-2067

No coin nor oath required. For personal study only.

✦ Synopsis

Lanthanide Schiff-base complexes with the formula [3,5-tBu 2 -2-(O)C 6 H 2 CH=NC 6 H 5 ] 3 Ln(THF) (Ln = Sc, Y, La, Nd, and Gd) were synthesized by the metathesis reaction of anhydrous LnCl 3 with a Schiff-base sodium salt in good yields (> 80%). The complex containing a neodymium center was characterized by X-ray diffraction and the structure around the neodymium atom could be described as a pentagonal bipyramid. The ring-opening polymerization (ROP) of Ξ΅-caprolactone (CL) was successfully carried out using the lanthanide Schiff-base complexes as catalysts, and the neodymium complex leads to a controlled ROP of CL. The influence of the reaction conditions on the monomer conversion, molecular weight, and molecular weight distribution of the resultant polymers was investigated. The polymerization rate was first-order with respect to the monomer concentration. End-group analyses of the oligomer of CL showed that the polymerization underwent a coordination-insertion mechanism.

πŸ“œ SIMILAR VOLUMES

Ring-opening polymerization of Ο΅-caprola
Ring-opening polymerization of Ο΅-caprolactone initiated by rare earth complex catalysts
✍ Xianmo Deng; Zhixue Zhu; Chengdong Xiong; Lianlai Zhang πŸ“‚ Article πŸ“… 1997 πŸ› John Wiley and Sons 🌐 English βš– 149 KB πŸ‘ 1 views

The polymerization of caprolactone ( 1-CL) was initiated by yttrium triisopropoxide {Y(OP i r ) 3 }, bimetallic isopropoxide of yttrium and aluminum {Y[Al(OP i s ) 4 ] 3 }, yttrium and tin(II) {Y[Sn(OP i r ) 3 ] 3 }, and tin(II) and yttrium {Sn[Y(OP i r ) 4 ] 2 }, respectively. The polymerization wa

Ring-opening polymerization of six-membe
Ring-opening polymerization of six-membered cyclic esters catalyzed by tetrahydroborate complexes of rare earth metals
✍ Yuushou Nakayama; Kenta Sasaki; Naoki Watanabe; Zhengguo Cai; Takeshi Shiono πŸ“‚ Article πŸ“… 2009 πŸ› Elsevier Science 🌐 English βš– 341 KB

Catalytic behavior of tetrahydroborate complexes of rare earth metals, Ln(BH 4 ) 3 (THF) x (1: ), for ring-opening polymerization (ROP) of six-membered cyclic esters, d-valerolactone (VL) and D,L-lactide (D,L-LA), was studied. The controlled polymerization of VL with 1-6 proceeded in THF at 60 C. T