SYNTHESIS AND CHARACTERIZATION OF FLUORO-SUBSTITUTED β-ENAMINOKETONATO TITANIUM COMPLEXES AND THEIR CATALYTIC BEHAVIOR OF REGIOSELECTIVE ETHYLENE/CYCLOPENTADIENE COPOLYMERIZATION  

作　　者：Yan-guo Li Miao Hong Gui-bao Zhang 李悦生 

机构地区：[1]State Key Laboratory of Polymer Physics and Chemistry,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences

出　　处：《Chinese Journal of Polymer Science》2013年第4期574-582,共9页高分子科学（英文版）

基　　金：supported by the National Natural Science Foundation of China (No. 21234006)

摘　　要：The ethylene/cyclopentadiene （CPD） copolymerization behavior by using fluoro-substituted bis（fl- enaminoketonato） titanium complexes [FC6H4NC（CH3）CHCO（CF3）]2TiC12 （la-lc） has been investigated in detail. Upon utilizing MMAO as a cocatalyst, complexes la-lc exhibit high catalytic activities, affording the copolymers with high molecular weight and unimodal molecular weight distribution. Compared with non-substituted complex [C6HsNC（CH3）CHCO（CF3）]2TiC12 （1）, complexes la-lc can produce the copolymers with CPD incorporation adjusted in a wide range due to the enhancement of electrophilicity of metal center caused by introducing electron-withdrawing groups. Especially complex lc bearing fluorine at the para-position of N-aryl moiety provides the highest CPD incorporation, which is nearly two times （18.5 mol%） higher than the non-substituted complex 1 （8.9 mol%） under the same conditions. The highest CPD incorporation up to 24.6 mol% can be easily achieved using this complex. 1H-and 13C-NMR spectra demonstrate that these fluoro-substituted complexes possess regioselective nature with exclusive 1,2-insertion fashion, and alternating ethylene-CPD sequence can be detected at high CPD incorporation.The ethylene/cyclopentadiene （CPD） copolymerization behavior by using fluoro-substituted bis（fl- enaminoketonato） titanium complexes [FC6H4NC（CH3）CHCO（CF3）]2TiC12 （la-lc） has been investigated in detail. Upon utilizing MMAO as a cocatalyst, complexes la-lc exhibit high catalytic activities, affording the copolymers with high molecular weight and unimodal molecular weight distribution. Compared with non-substituted complex [C6HsNC（CH3）CHCO（CF3）]2TiC12 （1）, complexes la-lc can produce the copolymers with CPD incorporation adjusted in a wide range due to the enhancement of electrophilicity of metal center caused by introducing electron-withdrawing groups. Especially complex lc bearing fluorine at the para-position of N-aryl moiety provides the highest CPD incorporation, which is nearly two times （18.5 mol%） higher than the non-substituted complex 1 （8.9 mol%） under the same conditions. The highest CPD incorporation up to 24.6 mol% can be easily achieved using this complex. 1H-and 13C-NMR spectra demonstrate that these fluoro-substituted complexes possess regioselective nature with exclusive 1,2-insertion fashion, and alternating ethylene-CPD sequence can be detected at high CPD incorporation.

关 键 词：Ziegler-Natta polymerization Titanium catalyst Cyclopentadiene copolymer. 

分 类 号：O631.5[理学—高分子化学]