Catalytic mechanism of ternary rare-earth-matal coordination catalysts in the copolymerization of carbon dioxide and epoxide
文献类型：期刊论文
| 作者 | Min Jiadong1,2; Zhang Yaming1; Chen Yuyan1; Wang Xianhong1; Zhao Xiaojiang1; Wang Fosong1 |
| 刊名 | Acta polymerica sinica
 |
| 出版日期 | 2009-03-20 |
| 期号 | 3页码:233-237 |
| 关键词 | Carbon dioxide Copolymerization Rare-earth-metal Xps Mechanism |
| ISSN号 | 1000-3304 |
| 通讯作者 | Min jiadong() |
| 英文摘要 | Ternary rare earth metal coordination catalysts prepared from y(ccl(3) coo)(3), glycerin, and znet(2), were confirmed to be effective for the copolymerization of carbon dioxide and various epoxides. whereas their precise modification was hampered by the lack of insight into active centers. here an x-ray pholoelectron spectroscopy (xps) technique was employed to study the interaction of various components, especially the central metal atoms in these catalysts. copolymerization experiments with typical conditions were also carried out to investigate the correlation between the binding energy (be) of central metals and the catalytic activity. the be of zn2p3/2 in y (ccl(3) coo)(3)-glycerin-znet(2) ternary catalyst was tested to be 0.3 ev higher than that in glycerin-znet(2) binary catalyst, while the be of 01s increased by 0.4 ev; on the contrary, the be of y3d5/2 in the ternary catalyst system decreased by 1.4 ev than that in y(ccl(3)coo)(3) while cl2p decreased by 1.6 ev. he be shifts showed that the rare-earth-metal compound has assuredly coordinated with zinc-oxygen bond in the ternary catalyst. active center for the copolymerization is the coordinating activated zinc-oxygen bond, and rare-earth-metal compounds shift the electron distribution of active center by a conjectured "double metal bridged coordinating" mode. electrons around zn partially flow to y via coordinating, resulting in decrease of electron cloud density and increase of the lewis acidity around catalytic centre. that makes the activated zinc-oxygen bond more liable to be attacked by carbon dioxide and epoxide monomer, thereby it enhances the catalytic activity. as a result, the activity of y (ccl(3) coo), based ternary catalyst reached 563.0 g polymer/(mol zn h) in the copolymerization, which is 23.6% higher than the activity of the binary catalyst system without rare-earth-metal compounds. yttrium compounds with various anionic groups were also investigated to study the influences of lewis acidity on central site. a consistent relationship was found among the pk(a) of ligands in yttrium compounds, be of the coordinated catalysts and catalytic activities. |
| WOS关键词 | PROPYLENE-OXIDE ; ALTERNATING COPOLYMERIZATION ; DIETHYLZINC ; CO2 |
| WOS研究方向 | Polymer Science |
| WOS类目 | Polymer Science |
| 语种 | 英语 |
| WOS记录号 | WOS:000264545600007 |
| 出版者 | SCIENCE PRESS |
| URI标识 | http://www.irgrid.ac.cn/handle/1471x/2393902 |
| 专题 | 中国科学院大学 |
| 通讯作者 | Min Jiadong |
| 作者单位 | 1.Chinese Acad Sci, Changchun Inst Appl Chem, Polymer Mat & Engn Lab, Changchun 130022, Peoples R China 2.Chinese Acad Sci, Grad Sch, Beijing 100039, Peoples R China |
| 推荐引用方式 GB/T 7714 | Min Jiadong,Zhang Yaming,Chen Yuyan,et al. Catalytic mechanism of ternary rare-earth-matal coordination catalysts in the copolymerization of carbon dioxide and epoxide[J]. Acta polymerica sinica,2009(3):233-237. |
| APA | Min Jiadong,Zhang Yaming,Chen Yuyan,Wang Xianhong,Zhao Xiaojiang,&Wang Fosong.(2009).Catalytic mechanism of ternary rare-earth-matal coordination catalysts in the copolymerization of carbon dioxide and epoxide.Acta polymerica sinica(3),233-237. |
| MLA | Min Jiadong,et al."Catalytic mechanism of ternary rare-earth-matal coordination catalysts in the copolymerization of carbon dioxide and epoxide".Acta polymerica sinica .3(2009):233-237. |
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来源：中国科学院大学
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