Internal electron donor compound for preparing α-olefin polymerization catalyst component

A method of preparing an α-olefin polymerization catalyst having a component comprising electron donor A and electron donor B, wherein electron donor A and electron donor B have a ratio determined by a method comprising:

• (1) adding an amount (“adding amount”) of the internal electron donor A to a catalyst carrier and measuring a corresponding amount loaded to the catalyst carrier (“load amount”) of the internal electron donor A;
• (2) repeating step (1) to obtain a plurality of the adding amounts and the corresponding load amounts of the internal electron donor A, and constructing a first load curve showing a relationship between the adding amounts (x-axis) and the corresponding load amounts (y-axis) of the internal electron donor A, x-axis and y-axis forming a coordinate plane;
• (3) adding an amount (“adding amount”) of the internal electron donor B into the catalyst carrier and measuring a corresponding amount loaded to the catalyst carrier (“load amount”) of the internal electron donor B;
• wherein A and B are mixed internal electron donors, the adding amount of A is x, the adding amount of B is y, A has a competition load amount xi, and B has a competition load amount yi;
• (4) repeating step (3) to obtain a plurality of the adding amounts and the corresponding load amounts of the internal electron donor B, and constructing a second load curve showing a relationship between the adding amounts (x-axis) and the corresponding load amounts (y-axis) of the internal electron donor B, x-axis and y-axis forming a coordinate plane and constructing a competition curve of the adding amount of A (x) versus the load amount of A (xi), x−xi;
• (5) fitting the first load curve by a least squares method by
• drawing a straight line p1 in a front portion passing a point where the adding amount and the load amount both read zero (“zero point”),
• drawing a straight line q1 in a rear portion passing the end point of the first load curve, and
• drawing a first arc line between the front portion and the rear portion of the first load curve and constructing a competition curve of the adding amount of B (y) versus the load amount of B (yi), y−yi;
• (6) fitting the second load curve by a least squares method by
• drawing a straight line p2 in a front portion passing a point where the adding amount and the load amount both read zero (“zero point”),
• drawing a straight line q2 in a rear portion passing the end point of the load curve, and
• drawing a second arc line in between the front portion and the rear portion of the second load curve, wherein an intersection of p1 and q1 has a load amount of a, wherein an intersection of p2 and q2 has a load amount of b, and a≥b, wherein an intersection of q1 and the first arc line has a load amount of a+m and an intersection of q2 and the second arc line has a load amount of b+n;
• (7) mixing an adding amount x of A and an adding amount y of B with the catalyst carrier;
• (8) measuring a compound competition load amount of A loaded to the catalyst carrier as xi and a compound competition load amount of B loaded to the catalyst carrier as yi, wherein 0<xi<a and 0<yi<b and b≤xi+yi≤a,
• (9) constructing a first compound competition load curve for the internal electron donor A and a second compound competition load curve for the internal electron donor B;
• (10) respectively selecting a load amount xk of the internal electron donor A from the first compound competition load curve and a load amount yk of the internal electron donor B from the second compound competition load curve, wherein b≤xk+yk≤a;
• (11) determining the adding amount of the internal electron donor A corresponding to xk based on the first compound competition load curve and the adding amount of the internal electron donor B corresponding to yk based on the second compound competition load curve;
• (12) preparing the catalyst component by adding to the carrier the adding amount of the internal electron donor A corresponding to xk and the adding amount of the internal electron donor B corresponding to yk;
• (13) testing the catalyst component obtained in step (12) in α-olefin polymerization, screening the catalyst component and determining the corresponding ratio of A to B;
• and
• (14) determining the load amounts of A and B in catalyst component as being xi and yi, respectively;
• adjusting xi and yi to xt and yt, respectively, provided that amount sum xi+yi follows a formula xi+yi≤xt+yt≤a+m+b+n to prepare the catalyst component and testing the catalyst component in α-olefin polymerization, and determining the corresponding ratio of A and B,
• wherein lines p1 and p2 pass the zero point of the coordinate plane, line q1 passes the end point of the first load curve, line q2 passes the end point of the second load curve,
• wherein
• the adding amount is the amount of the internal electron donor A or B added to the carrier,
• the load amount is the amount of the internal electron donor A or B loaded onto the carrier when only A or B is added to the carrier, and
• the competition load amount is the amount of the internal electron donor A or B loaded onto the carrier when both A and B are added to the carrier;
• wherein the internal electron donors A and B are different and independently selected from the group consisting of ethyl benzoate, ethyl p-methylbenzoate, ethyl p-Anisate, butyl benzoate, p-ethyl butyl benzoate, p-ethoxy butyl benzoate, dibutyl phthalate, diisobutyl phthalate, dibenzoate-2,4-pentanediol ester, di-m-chlorobenzoic-2,4-pentanediol ester, di-p-butylbenzoic-2,4-pentanediol ester, di-t-butylbenzoic-3-methyl-2,4-pentanediol ester, 2-(1-trifluoromethyl ethyl)-2-methyl diethyl malonate, 2-(1-trifluoromethyl ethylidene)diethyl malonate, 2-isopropylidene diethyl malonate, diethyl succinate, methyl diethyl succinate, 2,3-diisopropyl-2-ethyl diethyl succinate, dibutyl succinate, 2,3-diisopropyl dibutyl succinate, diisobutyl succinate, 2,3-diisopropyl diisobutyl succinate, 3,3-diisobutyl diethyl glutarate, 3-isopropyl-3-methyl diethyl glutarate, 3,3-dimethyl diisobutylglutarate, 3-methyl diisobutylglutarate, 2-methyl-diethyl glutarate, diisobutylglutarate, 9,9-bi s(methoxymethyl)fluorene, 5,5-bis(methoxymethyl)cyclopentadiene, 2,2′-dimethoxy-1,1′-biphenyl, 2,2′-dimethoxy-1,1′-binaphthyl, 2,2′-dimethoxy-1,1′-biphenanthrol, 2,2-diisopropyl-1,3-dimethoxypropane, 2,2-dibutyl-1,3-dimethoxypropane, 2,2-diisobutyl-1,3-dimethoxypropane, 2,2-di-t-butyl-1,3-dimethoxypropane, 2,2-diisoamyl-1,3-dimethoxypropane, 2,2-di-t-pentyl-1,3-dimethoxypropane, 2,2-diphenyl-1,3-dimethoxypropane, 2,2-dibenzyl-1,3-dimethoxypropane, 2-n-propyl-2-cyclohexyl-1,3-dimethoxypropane, 2-n-butyl-2-cyclohexyl-1,3-dimethoxypropane, 2-n-pentyl-2-cyclohexyl-1,3-dimethoxypropane, 2-isopentyl-2-isopropyl-1,3-dimethoxypropane, 2-isobutyl-2-isopropyl-1,3-dimethoxypropane, diethyl maleate, 2-cyclohexyl diethyl maleate, 2-isobutyl diethyl maleate, 2-n-amyl diethyl maleate, and 2-cyclopentyl diethyl maleate, and
• wherein the carrier comprises MgCl2.