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Received: 2003-09-25
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Study on the distribution of active centers in novel low Ti-loading MgCl2-supported Ziegler-Natta catalyst
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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.
@article{title="Study on the distribution of active centers in novel low Ti-loading MgCl2-supported Ziegler-Natta catalyst",
author="WANG Jian-feng, WANG Li, ZHAO Zhen-rong, WANG Wen-qing, CHEN Tao",
journal="Journal of Zhejiang University Science A",
volume="5",
number="8",
pages="912-917",
year="2004",
publisher="Zhejiang University Press & Springer",
doi="10.1631/jzus.2004.0912"
}
%0 Journal Article
%T Study on the distribution of active centers in novel low Ti-loading MgCl2-supported Ziegler-Natta catalyst
%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
%V 5
%N 8
%P 912-917
%@ 1869-1951
%D 2004
%I Zhejiang University Press & Springer
%DOI 10.1631/jzus.2004.0912
TY - JOUR
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
A1 - ZHAO Zhen-rong
A1 - WANG Wen-qing
A1 - CHEN Tao
J0 - Journal of Zhejiang University Science A
VL - 5
IS - 8
SP - 912
EP - 917
%@ 1869-1951
Y1 - 2004
PB - Zhejiang University Press & Springer
ER -
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.
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