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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",
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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
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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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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

[1] Bravakis, A.M., Bailey, L.E., Pigeon, M., Collins, S., 1998. Synthesis of elastomeric polypropylene using unsymmetrical zirconocene catalysts: marked reactivity difference of “Rac”- and “Meso”-like diastereomers. Macromolecules, 31:1000-1009.

[2] Doi, Y., Suzuki, E., Keii, T., 1981. Stereoregularities of polypropylenes obtained with highly active supported Ziegler-Natta catalyst systems. Makromol. Chem., Rapid Commun., 2:293-297

[3] Fan, Z.Q., Feng, L.X., Yang, S.L., 1991. Plurality of active centers on heterogeneous Ziegler-Natta catalyst. Chem. J. Chinese Univ, 12:1681-1685 (in Chinese).

[4] Jiang, J., Wu, Q., 1999. Progress in the synthesis of atactic polypropylene. Huagong Xingyin Cailiao, 9:15-17 (in Chinese).

[5] Kissin, Y.V., 1995. Molecular weight distributions of linear polymers: detailed analysis from GPC data. Journal of Polymer Science: Part A: Chemistry, 33:227-237.

[6] Locatelli, P., Sacchi, M.C., Tritto, I., Forlini, F., 1990. 13C NMR analysis of propene-butene copolymer. Steric structure of chain end groups and inhomogeneity of isotactic sites. Macromolecules, 23:2406-2409.

[7] Nele, M., Mohammed, M., Xin, S.X., Collins, S., Dias, M.L., Pinto, J.C., 2001. Two-state models for propylene polymerization using metallocene catalyst. 2. Application to ansa-metallocene catalyst systems. Macromolecules, 34:3830-3841.

[8] Shiono, T., Uchino, H., Soga, K., 1989. A highly non-stereospecific catalyst for propene polymerization. Polymer Bulletin, 21:19-21.

[9] Soga, K., Shiono, T., 1997. Ziegler-Natta catalysts for olefin polymerizations. Prog. Polym. Sci, 22:1503-1546.

[10] Tiemblo, P., Gomez-Elvira, J.M., Teyssedre, G., 1999. Degradative luminescent processes in atactic polypropylene. Chemiluminescence along the thermooxidation. Polymer Degradation and Stability, 66:41-47.

[11] Wang, L., Feng, L.X., Xu, J.T., Yang, S.L., 1995. Study on highly active Ziegler-Natta catalysts for polymerization of olefins. Chin. J. Polym. Sci., 13:41-50 (in Chinese).

[12] Xu, J.T., Feng, L.X., Yang, S.L., Yang, Y.Q., Kong, X.M., 1998. Temperature rising elution Fraction of polypropylene produced by heterogeneous Ziegler-Natta catalysts. European Polymer Journal, 34:431-434.

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