Study on the distribution of active centers in novel low Ti-loading MgCl2-supported Ziegler-Natta catalyst |
| |
Authors: | Wang Jian-Feng Wang Li Zhao Zhen-Rong Wang Wen-Qing Chen Tao |
| |
Affiliation: | State Key Lab of Polymer Reaction Engineering, College of Materials Science and Chemical Engineering, Zhejiang University, Hangzhou 310027, China. |
| |
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. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|