Enhancing stereoselectivity of propylene polymerization with MgCl2-supported Ziegler-Natta catalysts by electron donor: Strong effects of titanium dispersion state

被引：25

作者：

Jiang, Baiyu ^{[1
]}

He, Feng ^{[1
]}

Yang, Pengjia ^{[1
]}

Zhang, Zhen ^{[1
]}

Weng, Yuhong ^{[1
]}

Cheng, Zhenmei ^{[1
]}

Fu, Zhisheng ^{[1
]}

Fan, Zhiqiang ^{[1
]}

机构：

[1] Zhejiang Univ, Dept Polymer Sci & Engn, MOE Key Lab Macromol Synth & Functionalizat, Hangzhou 310027, Zhejiang, Peoples R China

来源：

CATALYSIS COMMUNICATIONS | 2019年 / 121卷

基金：

中国国家自然科学基金;

关键词：

Supported Ziegler-Natta catalyst; Propylene polymerization; Electron donor; Number of active centers; ACTIVE-CENTERS; SURFACE-DEFECTS; MGCL2; SURFACE; MODEL; ADSORPTION; MECHANISM; STABILIZATION; COADSORPTION; KINETICS; NUMBER;

D O I：

10.1016/j.catcom.2018.12.008

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Propylene polymerization with two TiCl4/MgCl2 catalysts (Cat-1: Ti 0.1%; Cat-2: Ti 1.0%) showed different responses to (cyclo-C5H9)(2)Si(OCH3)(2) (De) addition. Cat-i was deactivated more than Cat-2 by De. Amount of three groups of active centers producing atactic, medium isotactic and isotactic polypropylene chains were all reduced by De addition, but those of Cat-1 were reduced more. Reactivity of the isospecific active centers (k(pi)) was enhanced by De, but k(pi) of Cat-2 was changed more sensitively than Cat-1. The lower stereoselectivity of Cat-1 than Cat-2 are attributable to weaker De adsorption on its surface Mg, and the more sparsely dispersed Ti species on Cat-1 is responsible for weak De adsorption.

引用

页码：38 / 42

页数：5

共 32 条

[1] Effect of Hydrogen and External Donor on the Microstructure of Polypropylene Made with a 4th Generation Ziegler-Natta Catalyst [J].

Alshaiban, Ahmad ;

Soares, Joao B. P. .

MACROMOLECULAR REACTION ENGINEERING, 2013, 7 (3-4) :135-145

[2] Modeling the Stabilization of Surface Defects by Donors in Ziegler-Natta Catalyst Support [J].

Bazhenov, Andrey ;

Linnolahti, Mikko ;

Pakkanen, Tapani A. ;

Denifl, Peter ;

Leinonen, Timo .

JOURNAL OF PHYSICAL CHEMISTRY C, 2014, 118 (09) :4791-4796

[3] Modeling Coadsorption of Titanium Tetrachloride and Bidentate Electron Donors on Magnesium Dichloride Support Surfaces [J].

Bazhenov, Andrey S. ;

Denifl, Peter ;

Leinonen, Timo ;

Pakkanen, Anneli ;

Linnolahti, Mikko ;

Pakkanen, Tapani A. .

JOURNAL OF PHYSICAL CHEMISTRY C, 2014, 118 (48) :27878-27883

[4] Mechanism of olefin polymerization on supported Ziegler-Natta catalysts based on data on the number of active centers and propagation rate constants [J].

Bukatov, GD ;

Zakharov, VA ;

Barabanov, AA .

KINETICS AND CATALYSIS, 2005, 46 (02) :166-176

[5] Periodic Hybrid DFT Approach (Including Dispersion) to MgCl2-Supported Ziegler-Natta Catalysts. 2. Model Electron Donor Adsorption on MgCl2 Crystal Surfaces [J].

Capone, Fabio ;

Rongo, Luca ;

D'Amore, Maddalena ;

Budzelaar, Peter H. M. ;

Busico, Vincenzo .

JOURNAL OF PHYSICAL CHEMISTRY C, 2013, 117 (46) :24345-24353

[6] Polyolefins - Catalyst and Process Innovations and their Impact on Polymer Properties [J].

Chadwick, John C. .

MACROMOLECULAR REACTION ENGINEERING, 2009, 3 (08) :428-432

[7] Adsorption of TiCl4 and electron donor on defective MgCl2 surfaces and propylene polymerization over Ziegler-Natta catalyst: A DFT study [J].

Cheng, Rui-hua ;

Luo, Jun ;

Liu, Zhen ;

Sun, Jing-wen ;

Huang, Wei-huan ;

Zhang, Ming-ge ;

Yi, Jian-jun ;

Liu, Bo-ping .

CHINESE JOURNAL OF POLYMER SCIENCE, 2013, 31 (04) :591-600

[8] Key elements in the structure and function relationship of the MgCl2/TiCl4/Lewis base Ziegler-Natta catalytic system [J].

Correa, Andrea ;

Piemontesi, Fabrizio ;

Morini, Giampiero ;

Cavallo, Luigi .

MACROMOLECULES, 2007, 40 (25) :9181-9189

[9] Toward a Unified Model Explaining Heterogeneous Ziegler-Natta Catalysis [J].

Credendino, Raffaele ;

Liguori, Dario ;

Fan, Zhiqiang ;

Morini, Giampiero ;

Cavallo, Luigi .

ACS CATALYSIS, 2015, 5 (09) :5431-5435

[10] DISSOCIATION OF COMPLEXES OF TRIETHYLALUMINUM WITH ELECTRON-DONORS ON DILUTION [J].

DENISOV, VM ;

TOPORKOVA, EB ;

ALFEROVA, LV ;

KOLTSOV, AI .

BULLETIN OF THE ACADEMY OF SCIENCES OF THE USSR DIVISION OF CHEMICAL SCIENCE, 1975, 24 (01) :146-147

← 1 2 3 4 →