| abstract |
A catalyst for homopolymerizing and copolymerizing propylene and its preparation and use. The catalyst component includes titanium compound containing at least one Ti-halogen bond and at least two kinds of electron donor compounds A and B supported on MgCl 2 .nROH adduct, wherein the electron donor compound A is a compound of formula (I), the electron donor compound B is ester or ether compound; the molar ratio between compound A and compound B is 0.1-5; the molar ratio between the total amounts of the two kinds of electron donors and MgCl 2 .nROH is 0.01-1, based on the amount of MgCl 2 .nROH; and the molar ration between the titanium compound containing Ti-halogen bond and MgCl 2 .nROH is 1-200. The catalyst has high activity, high stereospecificity and good copolymerization performance. In addition, the morphology of the polymer obtained therefrom is good. |