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Both metallocene catalysts have high activity and a narrow molecular weight distribution and excellent catalytic ability of polymerization, etc., there are also some disadvantages, such as the morphology of the polymer poor, not suitable for the continuous slurry polymerization and gas phase fluidized bed polymerization process, the maximum activity of the metallocene catalyst requires a lot of expensive MAO cocatalyst like. If the soluble metallocene compound supported on a carrier to obtain the supported catalyst, so that both homogeneous and heterogeneous catalysts characteristics of the catalyst, not only can make certain disadvantages homogeneous catalysts, and can be in a slurry method and the Gas production of the device application. ZN catalysts used in the polyolefin industry, various inorganic carrier (SiO 2 , Al 2 O 3 , MgCl 2 < / sub>, etc.) is often used to prepare the supported catalyst, to improve the catalyst activity. But the use of these supported catalysts, the inorganic carrier is incorporated into the polymer affect the performance of the polyolefin. Therefore, to explore organic supported catalysts are still scientific and practical significance. In recent years, there has as carrier polymer catalyst, and a growing concern. The subjects of the rapid expansion of supercritical solutions (RESS) and the preparation of the catalyst carrier (polystyrene) fine particles precipitated by the two of the catalyst supported on the support of polystyrene fine particles, thereby preparing the supported metallocene catalyst. This supported catalyst with MAO as cocatalyst, the catalytic polymerization of ethylene slurry, influence of different polymerization conditions such as polymerization temperature, polymerization pressure, and Al-Ti ratio on catalytic activity and the resulting viscosity average molecular weight of polyethylene. The results show that the catalytic activity increased with the polymerization temperature, polymerization pressure increases; when the Al-Ti ratio is less than 2000, the activity increased with the increase of Ti ratio of aluminum, the aluminum titanium ratio equal to 2000, the activity reached the maximum, and then with aluminum Ti ratio increases. Viscosity average molecular weight with temperature, decreases with increasing Al Ti ratio, the viscosity average molecular weight increases with increasing pressure. Prepared by RESS supported metallocene catalyst has high catalytic activity, and other than that of modified SiO Ihm out of the obtained body of the supported metallocene catalyst with high catalytic activity. The paper also the catalyst particles and the polymer morphology were studied by SEM analysis showed that the microstructure of the surface of the catalyst particles showed the typical morphology five kinds of morphological characteristics, namely: spherulitic morphology characteristics, cobweb-like morphological structure ball-shaped morphology characteristic stacked, morphological characteristics and platelet-like morphology characteristic of walnut. The resulting polymer particles by SEM, and found submicroscopic polyethylene particles exhibit morphology four typical morphology, i.e. spherulitic morphology, fungus-like morphology, platelet-like morphology and morphological structure of cocoons . Seen, the catalyst particle morphology and their corresponding relationship exists between the polymer particles, the replication relationship. And to explore the formation of these morphological structure of reason.
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