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Journal of Zhejiang University SCIENCE A 2004 Vol.5 No.8 P.912~917

http://doi.org/10.1631/jzus.2004.0912


Study on the distribution of active centers in novel low Ti-loading MgCl2-supported Ziegler-Natta catalyst


Author(s):  WANG Jian-feng, WANG Li, ZHAO Zhen-rong, WANG Wen-qing, CHEN Tao

Affiliation(s):  State Key Lab of Polymer Reaction Engineering, College of Materials Science and Chemical Engineering, Zhejiang University, Hangzhou 310027, China; more

Corresponding email(s):   opl_wl@dial.zju.edu.cn

Key Words:  Supported Ziegler-Natta catalyst, Propylene polymerization, Active center, Molecular weight distribution


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WANG Jian-feng, WANG Li, ZHAO Zhen-rong, WANG Wen-qing, CHEN Tao. Study on the distribution of active centers in novel low Ti-loading MgCl2-supported Ziegler-Natta catalyst[J]. Journal of Zhejiang University Science A, 2004, 5(8): 912~917.

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author="WANG Jian-feng, WANG Li, ZHAO Zhen-rong, WANG Wen-qing, CHEN Tao",
journal="Journal of Zhejiang University Science A",
volume="5",
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pages="912~917",
year="2004",
publisher="Zhejiang University Press & Springer",
doi="10.1631/jzus.2004.0912"
}

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%A WANG Jian-feng
%A WANG Li
%A ZHAO Zhen-rong
%A WANG Wen-qing
%A CHEN Tao
%J Journal of Zhejiang University SCIENCE A
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T1 - Study on the distribution of active centers in novel low Ti-loading MgCl2-supported Ziegler-Natta catalyst
A1 - WANG Jian-feng
A1 - WANG Li
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A1 - WANG Wen-qing
A1 - CHEN Tao
J0 - Journal of Zhejiang University Science A
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SP - 912
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%@ 1869-1951
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DOI - 10.1631/jzus.2004.0912


Abstract: 
Novel MgCl2-supported Ziegler-Natta (Z-N) catalysts prepared using a new one-pot ball milling method can effectively control the amounts of Ti-loading in the catalysts. Complex GPC data on polypropylene synthesized by these novel catalysts were analyzed using the method of fitting the molecular weight distribution (MWD) curves with a multiple Flory-Schulz function. It was found that multiple active centers exist in these novel catalysts. Detailed study of the effects of the Ti-loadings in the catalysts on the distribution of the active centers showed that the Ti-loadings in the novel MgCl2-supported Z-N catalysts might affect the proportion of each type of active centers; and might be the main factor responsible for the effect of the Ti-loadings on the microstructure, the molecular weight and molecular weight distribution width of the resultant polymer, the catalytic activity and polymerization kinetics.

Darkslateblue:Affiliate; Royal Blue:Author; Turquoise:Article

Reference

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