Olefin Polymerization Catalyst and a Combined Catalyst Containing the Same

An olefin polymerization catalyst comprising a reaction product of:

• a magnesium dialkoxide, a titanium compound, an electron donor compound A and an electron donor compound B;
• wherein the electron donor compound A is a sulfonyl compound represented by general formula I:
• wherein X is selected from a group consisting of a disubstituted or unsubstituted group 14 element atom, a monosubstituted or unsubstituted group 15 element atom, and group 16 element atom, where the substituent is selected from a group consisting of a monocyclic, polycyclic or heteroatom-containing cyclic group and an aliphatic chain group;
• R1 and R2 are the same or different, and are respectively selected from a group consisting of hydrogen atom, halogen atom, substituted or unsubstituted alkyl, cycloalkyl, aryl, aralkyl, alkylaryl and heteroatom-containing cyclic group;
• the electron donor compound B is selected from a group consisting of an ester compound and an ether compound;
• the titanium compound has a general formula of Ti(OQ)4-nYn, where Q is selected from a group consisting of C1-C14 aliphatic hydrocarbyl and aromatic hydrocarbyl, Y is a halogen atom, n is an integer of 0 to 4;
• wherein when n is 2 or less, Q is the same or different;
• the electron donor compound A is used in an amount of 0.01 to 1 mole with respect to 1 mole of magnesium in the magnesium dialkoxide;
• the electron donor compound B is used in an amount of 0.01 to 1 mole with respect to 1 mole of magnesium in the magnesium dialkoxide;
• and
• the titanium compound is used in an amount of 0.5 to 100 mole(s) with respect to 1 mole of magnesium in the magnesium dialkoxide.