Fundamental aspects of heterogeneous Ziegler–Natta olefin polymerization catalysis: an experimental and computational overview

2020 ◽  
Vol 11 (38) ◽  
pp. 6107-6128
Author(s):  
Jugal Kumawat ◽  
Virendra Kumar Gupta

Using an internal/external donor containing MgCl2-supported Ziegler–Natta catalyst is one of the important processes for polyolefin production.

1999 ◽  
Vol 39 (7) ◽  
pp. 1257-1264 ◽  
Author(s):  
Tae Oan Ahn ◽  
Sung Chul Hong ◽  
Wan Soo Huh ◽  
Young-Chul Lee ◽  
Dong-Ho Lee

1994 ◽  
Vol 116 (14) ◽  
pp. 6435-6436 ◽  
Author(s):  
Ruhksana Quyoum ◽  
Qinyan Wang ◽  
Marie-Jose Tudoret ◽  
Michael C. Baird ◽  
Daniel J. Gillis

e-Polymers ◽  
2011 ◽  
Vol 11 (1) ◽  
Author(s):  
Song-tao Tu ◽  
Jun-qin Lou ◽  
Zhi-sheng Fu ◽  
Zhi-qiang Fan

AbstractIn this work, the effects of two silane type external donors, Ph2Si(OCH3)2 (DPDMS) and dicyclopentyldimethoxysilane (DCPDMS) on propylene slurry polymerization in the presence of hydrogen with a MgCl2/TiCl4/DIBP - Al(C2H5)3 catalyst system were investigated, and the tacticity distribution and molecular weight distribution (MWD) of polypropylene (PP) were further regulated by using silane/ether (ROCH3, R = n-Bu, i-C8H17) composite external donors. The tacticity distribution of PP, as revealed by successive self-nucleation and annealing (SSA) thermo analysis of the polymer, is markedly changed by the external donors. DCPDMS shows much stronger effects than DPDMS. Addition of the ether as an auxiliary external donor in MgCl2/TiCl4/DIBP-TEA/silane (DPDMS or DCPDMS) lead to further increase in catalytic activity and isotacticity of PP, and changes in tacticity distribution. By using the composite external donors, PP with both higher isotacticity index, lower molecular weight or narrower molecular weight distribution was prepared at high activity. Effects of the external donors on the active center distribution were discussed based on the results of deconvoluting the MWD curve with multiple Flory “most-probable” distributions, and possible mechanism of the external donor effects was proposed.


2005 ◽  
Vol 99 (3) ◽  
pp. 945-948 ◽  
Author(s):  
Li Wang ◽  
Hao-Jie Yu ◽  
Zhen-Li Ma ◽  
Zhao-Yang Ye ◽  
Shan Jiang ◽  
...  

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