| abstract |
The present invention provides catalyst active components used in ethylene polymerization or polymerization, the catalyst precursors as well as the preparation method of the catalyst active components. The catalyst active components in the present invention comprise: magnesium compounds; titanium compounds Ti (OR) <SUB> 4-n </ SUB> X <SUB> n </ SUB>, where X is halogen, R is alkyl, n is O or an integer less than or equals 4; catalytic accelerant which is of chelate function and is of matching iron of [O,O] or[O,N]; Electron donor with silicon; Organic ester R'OH, where R' represents alkyl; and halogenated hydrocarbon. The catalyst precursors provided in the present invention are firm particles with high catalytic activity, stable dynamics and good polymerization and hydrogen-sensitive performance. The polyethylene products obtained from the catalyst precursors are particles of good shape, with the particle diameter evenly distributed. The density of the particles is high. |