首页>
外国专利>
Prepolymerization catalyst for use in gas phase polymerization of olefins and process for producing the same
Prepolymerization catalyst for use in gas phase polymerization of olefins and process for producing the same
展开▼
机译:用于烯烃气相聚合的预聚合催化剂及其制备方法
展开▼
页面导航
摘要
著录项
相似文献
摘要
A prepolymerization catalyst for use in a gas phase polymerization of an olefin or combinations of olefins which comprises (A) a solid catalyst component comprising magnesium, halogen, titanium and an electron donor and having a weight-average particle diameter of 15 to 45 µm, (B) at least one organoaluminum compound and (C) a prepolymer of an ethylene and/or at least one α-olefin, wherein the molar ratio of aluminum to titanium in the prepolymerization catalyst (Al/Ti ratio) is 3 to 11 (mol/mol), the weight ratio of the prepolymerization catalyst to the solid catalyst component (prepolymerization catalyst/solid catalyst component) is 2 to 35 (g/g), the content of volatile materials (VM) in the prepolymerization catalyst is 2.0% by weight or less, and the intrinsic viscosity [η] measured in tetralin at 135°C is 2.0 dl/g or less, and a process for a production thereof.;According to the present invention, a prepolymerization catalyst for gas phase polymerization of olefins showing a high activity in gas phase polymerization, not forming aggregates and coarse particles markedly at the time of prepolymerization, having a high bulk density and an excellent fluidity, not causing a marked entraining of prepolymerization catalyst and product powder out of the fluidized bed and nearly completely free from a formation of aggregates, at the time of gas phase polymerization, and giving an olefin polymer having a low content of cold xylene-soluble fraction can be provided.
展开▼