Zinc complexes containing asymmetrical N,N,O-tridentate ligands and their application in lactide polymerization
Gao, B; Duan, R; Pang, X; Li, X; Qu, Z; Shao, H; Wang, X; Chen, X
| HERO ID | 2294058 |
|---|---|
| In Press | No |
| Year | 2013 |
| Title | Zinc complexes containing asymmetrical N,N,O-tridentate ligands and their application in lactide polymerization |
| Authors | Gao, B; Duan, R; Pang, X; Li, X; Qu, Z; Shao, H; Wang, X; Chen, X |
| Journal | Dalton Transactions (Online) |
| Volume | 42 |
| Issue | 46 |
| Page Numbers | 16334-16342 |
| Abstract | A series of zinc complexes based on asymmetrical N,N,O-tridentate ligands were prepared via binaphthyl diamine derivatives. These complexes were characterized and employed as catalysts in lactide polymerization. The X-ray diffraction analyses revealed that molecular structures of 1b and 2b were mononuclear complexes with zinc atoms in distorted octahedral geometries. Upon co-catalysis with isopropanol, complex 2a showed the highest activity among these zinc complexes for the ring-opening polymerization of L-lactide, and complex 3a exhibited the highest stereoselectivity for the ring-opening polymerization of rac-lactide affording substantially isotactic polylactide (PLA) with a P(m) of 0.62. The polymerization kinetics using 2a as a catalyst was studied in detail. The kinetics of the polymerization results revealed that the rates of polymerization were first-order both in the monomer and the catalyst, and there was a linear relationship between the L-LA conversion and the number-average molecular weight of PLA with a narrow molecular distribution (1.07-1.17). The activation energy (31.49 kJ mol(-1)) was deduced according to the Arrhenius equation. |
| Doi | 10.1039/c3dt52016a |
| Pmid | 24065120 |
| Wosid | WOS:000326783200015 |
| Is Certified Translation | No |
| Dupe Override | No |
| Is Public | Yes |
| Language Text | English |