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

Abstract

An internal electron donor compound for preparing α-olefin polymerization catalyst component, including two kinds of electron donors; the proportion of the two kinds of electron donors in the compounding preparation of the catalyst is determined via designed experiments so as to obtain a catalyst component having good comprehensive performance or a particular performance. The electron donor compound of the present invention can be used in the preparation of α-olefin polymerization and co-polymerization catalyst component, particular the preparation of propylene polymerization catalyst component, and is applicable to prepare the propylene polymerization catalyst component by reacting magnesium chloride-ethanolscomlex compound carrier with titanium tetrachloride and electron donors, or to directly prepare the propylene polymerization catalyst component by reacting magnesium chloride, alcohols, titanium tetrachloride, and internal electron donor. In addition, also provided is a theoretical basis for selecting a proper electron donor combination from a plurality of electron donors.

Claims

1. 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 x.sup.i, and B has a competition load amount y.sup.i; (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 (x.sup.i), x−x.sup.i; (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 (y.sup.i), y−y.sup.i; (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 x.sup.i and a compound competition load amount of B loaded to the catalyst carrier as y.sup.i, wherein 0<x.sup.i<a and 0<y.sup.i<b and b≤x.sup.i+y.sup.i≤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 x.sup.k of the internal electron donor A from the first compound competition load curve and a load amount y.sup.k of the internal electron donor B from the second compound competition load curve, wherein b≤x.sup.k+y.sup.k≤a; (11) determining the adding amount of the internal electron donor A corresponding to x.sup.k based on the first compound competition load curve and the adding amount of the internal electron donor B corresponding to y.sup.k 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 x.sup.k and the adding amount of the internal electron donor B corresponding to y.sup.k; (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 x.sup.i and y.sup.i, respectively; adjusting x.sup.i and y.sup.i to x.sup.t and y.sup.t, respectively, provided that amount sum x.sup.i+y.sup.i follows a formula x.sup.i+y.sup.i≤x.sup.t+y.sup.t≤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 MgCl.sub.2.

2. The method according to claim 1, wherein the electron donors A and B are applicable for preparing propylene polymerization catalyst component.

3. The method according to claim 2, wherein the internal electron donors A and B are different and independently selected from the group consisting of 9,9-bis(methoxymethyl)fluorene, dibutyl phthalate, diisobutyl phthalate, 2,3-diisopropyldibutyl succinate, and 2,2′-dimethoxy-1,1′-binaphthyl.

4. The method according to claim 2, wherein a combination of internal electron donors A and B is one of the following combinations: 9,9-bis(methoxymethyl)fluorene and dibutyl phthalate, 9,9-bis(methoxymethyl)fluorene and diisobutyl phthalate, 9,9-bis(methoxymethyl)fluorene and 2,3-diisopropyldibutyl succinate, 9,9-bis(methoxymethyl)fluorene and 2,2′-dimethoxy-1,1′-binaphthyl, dibutyl phthalate and 2,3-diisopropyldibutyl succinate, dibutyl phthalate and 2,2′-dimethoxy-1,1′-binaphthyl, diisobutyl phthalate and 2,3-diisopropyldibutyl succinate, or diisobutyl phthalate and 2,2′-dimethoxy-1,1′-binaphthyl.

5. The method according to claim 1, wherein a combination of the internal electron donors A and B is one of the following combinations: 9,9-bis(methoxymethyl)fluorene and dibutyl phthalate, 9,9-bis(methoxymethyl)fluorene and diisobutyl phthalate, 9,9-bis(methoxymethyl)fluorene and 2,3-diisopropyldibutyl succinate, 9,9-bis(methoxymethyl)fluorene and 2,2′-dimethoxy-1,1′-binaphthyl, dibutyl phthalate and 2,3-diisopropyldibutyl succinate, dibutyl phthalate and 2,2′-dimethoxy-1,1′-binaphthyl, diisobutyl phthalate and 2,3-diisopropyldibutyl succinate, or diisobutyl phthalate and 2,2′-dimethoxy-1,1′-binaphthyl.

6. The method according to claim 1, wherein the internal electron donor A or B is 2,2′-dimethoxy-1,1′-binaphthyl or 2,3-diisopropyl dibutyl succinate.

7. The method according to claim 1, wherein the internal electron donor A or B is 2,2′-dimethoxy-1,1′-binaphthyl or 9,9-bis(methoxymethyl)fluorene.

8. The method according to claim 1, wherein the α-olefin polymerization catalyst component is homopolymerization catalyst component of α-olefin and co-polymerization catalyst component of α-olefin and ethylene.

9. The method according to claim 1, wherein the α-olefin polymerization catalyst component is propylene polymerization catalyst component.

10. The method according to claim 9, wherein the propylene polymerization catalyst component is prepared by reacting magnesium chloride-alcohols complex compound carrier with titanium tetrachloride and the internal electron donor compound.

11. The method according to claim 10, wherein the steps for preparing propylene polymerization catalyst component using magnesium chloride-alcohols complex compound carder with titanium tetrachloride and the internal electron donor compound are as follows: providing a magnesium chloride-alcohols complex compound, mixing the magnesium chloride-alcohols complex compound with titanium tetrachloride at a ratio of 1 gram: 15-25 mL at the temperature of −20° C. to −10° C., with stirring and heating them to 110° C., and adding the electron donor compound during the heating process of 30° C. to 110° C., then allowing a reaction to undergo 1-3 hours at 110° C., followed by filtering and then adding the same amount of titanium tetrachloride to react 1-3 hours at the temperature of 110° C. to 120° C., and finally washing and drying the product to obtain the propylene polymerization catalyst component.

12. The method according to claim 9, wherein the propylene polymerization catalyst component is directly prepared by reacting magnesium chloride, alcohols, the internal electron donor compound and titanium tetrachloride.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention has 8 drawings:

(2) FIG. 1 shows the load curve of 2,3-diisopropyl di butyl succinate;

(3) FIG. 2 shows the load curve of 2,3-diisopropyl dibutyl succinate and its compound competition load curves with 9,9-bis(methoxymethyl)fluorene and dibutyl phthalate respectively;

(4) FIG. 3 shows the load curves of five electron donors in Embodiment I;

(5) FIG. 4 shows the load curve of 9,9-bis(methoxymethyl)fluorene in Embodiment 3;

(6) FIG. 5 shows the load curve of 2,2′-dimethoxy-1,1′-binaphthyl in Embodiment 3;

(7) FIG. 6 shows the load curve of 9,9-bis(methoxymethyl)fluorene and its compound competition load curve with 2,2′-dimethoxy-1,1′-binaphthyl in Embodiment 3;

(8) FIG. 7 shows the load curve of 2,2′-dimethoxy-1,1′-binaphthyl and its compound competition load curve with 9,9-bis(methoxymethyl)fluorene in Embodiment 3;

(9) FIG. 8 shows the load curves of two kinds of electron donors in Embodiment 5.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(10) The following nonrestrictive embodiments can enable those ordinary persons skilled in the art to comprehensively understand the principle, process and method of the present invention, without limiting the present invention in any way.

(11) Note: In the following embodiments, unless otherwise stated, the experiment operating procedures for preparation of catalyst component and determination of internal electron donor loading amount in the catalyst component and evaluation of catalyst component performance by propylene polymerization are carried out according to the following processes.

(12) Preparation of Catalyst Component:

(13) Add TiCl.sub.4 into a dry glass reactor with nitrogen protection and cool it down to −20° C., add microsphere magnesium chloride-ethanols complex compound carrier (the ratio of magnesium to ethanols is 2.9:1) by stirring, the mixing ratio of carrier to TiCl.sub.4 is 1 g:20 mL. Uniformly heat the aforementioned reaction mixture from −20° C. to 0° C., and then heat it to 70° C., add internal electron donor into the reactor (add two kinds of electron donors if compounding electron donors, and the detailed adding way please see the embodiments). Heat the reaction mixture to 110° C., and continue to react 2 h; suction filtrate the product, and add an equal amount of freshly-prepared TiCl4 again, heat them to 120° C. and continue to react 2 h, suction filtrate the product, wash the filter cake by hexane and dry it under vacuum condition to get a catalyst component.

(14) Determination of loading amount of internal electron donor: determine the loading amount of internal electron donor in the catalyst component by using the commonly-used analytical method in industry.

(15) Experiment operating procedures for evaluation of catalyst component performance by propylene polymerization:

(16) Add successively 0.1 mL external electron donor of dicyclopentyldimethoxysilane and 4.0 mL cocatalyst of hexane solution of triethylaluminum (1 mol/L) and 0.005 mmol (calculated by titanium) catalyst component prepared by the present invention to a 2 L well-dried and propylene-replacemented autoclave, import 1.5 L of liquid propylene and 0.2 MPa hydrogen, stir them at room temperature and mix uniformity, heat them to 70° C. and react 2 h with stirring, open the autoclave to take out the polypropylene, and cool it down to the room temperature; after the propylene is fully volatilized, weigh the mass of the product and calculate the activity of the catalyst, determine the polypropylene performance of isotacticity, bulk density, melt index, particle size distribution, and molecular weight distribution, etc.

Embodiment 1

(17) Preparation of catalyst component with a single internal electron donor: using internal electron donor of 9,9-bis(methoxymethyl)fluorene as an example.

(18) Prepare series of catalyst components by 9,9-bis(methoxymethyl)fluorene as internal electron donor, the adding amounts of 9,9-bis(methoxymethyl)fluorine are 0.08, 0.30, 0.45, 0.60, 0.75, 0.86, and 1.10 mmol/g.Math.carrier respectively. Determine the loading amounts of 9,9-bis(methoxymethyl)fluorene in the catalyst components, which are 1%, 6%, 9%, 11.5%, 14.5%, 17.5%, and 17.6% respectively, and make the adding-loading amount load curves.

(19) Carry out the operations same as the above preparation steps and prepare the catalyst components by dibutyl phthalate, diisobutyl phthalate, 2,3-diisopropyl dibutyl succinate, and 2,2′-dimethoxy-1, F-binaphthyl as the internal electron donors respectively. Determine the loading amounts of internal electron donors in the catalyst components, and make the adding-loading amount load curves respectively.

(20) The load curves of these internal electron donors all can be fitted to two straight lines, which are connected by an arc line. FIG. 3 shows the straight lines of the five internal electron donors' load curves before the turning points, and the slopes of the straight lines are: 2,3-diisopropyl dibutyl succinate's slope>dibutyl phthalate's≈diisobutyl phthalate's>2,2′-dimethoxy-1,1′-binaphthyl's>9,9-bis(methoxymethyl)fluorene's. The loading amounts at the turning points are: 16% for 9,9-bis(methoxymethyl)fluorene, 14% for 2,3-diisopropyl dibutyl succinate, 8% for dibutyl phthalate, 8% for diisobutyl phthalate, and 7% for 2,2′-dimethoxy-1,1′-binaphthyl. In these cases, the catalyst components have high catalyst activity and better comprehensive performance.

Embodiment 2

(21) Preparation of propylene polymerization catalyst component of two kinds of internal electron donors:

(22) Compounding 9,9-bis(methoxymethyl)fluorene with dibutyl phthalate as an example.

(23) When preparing catalyst component, the sum of the loading amounts of two kinds of electron donors are controlled within the range of 8%-16% according to FIG. 3. When heating the reaction mixture to 70° C., simultaneously add 9,9-bis(methoxymethyl)fluorene and dibutyl phthalate dissolved in toluene into the reaction mixture to prepare series of compound catalyst components, and determine their respective adding-loading amount competition load curve.

(24) The above method is also applicable to the preparation of two kinds of internal electron donor catalyst components by the combinations of 9,9-bis(methoxymethyl)fluorene and diisobutyl phthalate, 9,9-bis(methoxymethyl)fluorene and 2,3-diisopropyl dibutyl succinate, 9,9-bis(methoxymethyl)fluorene and 2,2′-dimethoxy-1,1′-binaphthyl, di butyl phthalate and diisobutyl phthalate, dibutyl phthalate and 2,3-diisopropyl dibutyl succinate, dibutyl phthalate and 2,2′-dimethoxy-1,1′-binaphthyl, diisobutyl phthalate and 2,3-diisopropyl di butyl succinate, diisobutyl phthalate and 2,2′-dimethoxy-1,1′-binaphthyl; and control the compound loading amounts of 9,9-bis(methoxymethyl)fluorene and diisobutyl phthalate, 9,9-bis(methoxymethyl)fluorene and 2,3-diisopropyl dibutyl succinate, 9,9-bis(methoxymethyl)fluorene and 2,2′-dimethoxy-1,1′-binaphthyl, dibutyl phthalate and diisobutyl phthalate, dibutyl phthalate and 2,2′-dimethoxy-1,1′-binaphthyl, diisobutyl phthalate and 2,3-diisopropyl dibutyl succinate, diisobutyl phthalate and 2,2′-dimethoxy-1,1′-binaphthyl within 16%-8, 16%-14%, 16%-7%, 8%, 8%-7%, 14%-8%, 8%-7% respectively. Determine each internal electron donor's respective compound adding-loading amount competition load curve.

(25) All the compound competition load curves are straight lines, but their slopes are not identical with that showed in FIG. 3, and the competitive load capacities of internal electron donors are as follow: 9,9-bis(methoxymethyl)fluorene>dibutyl phthalate≈diisobutylphthalate>2,3-diisopropyl di butyl succinate>2,2′-dimethoxy-1,1′-binaphthyl. The competitive load capacity of di butyl phthalate is equivalent to the diisobutyl phthalate's, and their respective compound loading value is identical to the loading value at the turning point, both about 8%.

Embodiment 3

(26) Prepare catalyst component by the compound of 9,9-bis(methoxymethyl)fluorene (A) and 2,2′-dimethoxy-1,1′-binaphthyl (B) as internal electron donor.

(27) FIG. 4 shows the load curve of 9,9-bis(methoxymethyl)fluorene; FIG. 5 shows the load curve of 2,2′-dimethoxy-1,1′-binaphthyl; FIG. 6 shows the load curve of 9,9-bis(methoxymethyl)fluorene and its compound competition load curve with 2,2′-dimethoxy-1,1′-binaphthyl; FIG. 7 shows the load curve of 2,2′-dimethoxy-1,1′-binaphthyl and its compound competition load curve with 9,9-bis(methoxymethyl)fluorene;

(28) Take values from the respective compound competition load curve of 9,9-bis(methoxymethyl)fluorene and 2,2′-dimethoxy-1,1′-binaphthyl obtained in embodiment 2 as the expected load values. According to the experiment results of embodiments 1 and 2,9,9-bis(methoxymethyl)fluorene has a stronger competitive capacity, and its maximum loading amount is about 16%, thus control the total expected loading amount at 7%-16%. Prepare compound catalyst components, the part expected loading values and loading values of internal electron donor components and the performances of catalyst components are showed in table 1.

(29) TABLE-US-00001 TABLE 1 Expected loading values and loading values of compounding A with B as internal electron donor, and the performances of catalyst components Total adding Total amount bulk expected of Di/ Loading Loading Catalyst density iso- loading mmol .Math. amount amount activity/ of PP/ tacticity value (g .Math. of of kgPP .Math. gPP .Math. of of Di/% carrier).sup.−1 A/wt % B/wt % (g .Math. cat).sup.−3 cm.sup.−3 PP/% 10.0 0.51 5.2 5.0 45 0.36 95.0 12.5 0.61 10.1 2.0 63 0.19 97.6 15.0 0.73 13.0 2.0 65 0.41 98.4 17.5 0.85 15.1 0.9 54 0.43 98.7 Note: Di-internal electron donor; PP-polypropylene; A—9,9-bis(methoxymethyl)fluorene; B—2,2′-dimethoxy-1, 1′-binaphthyl; hereinafter the same.

(30) When the loading amount of 9,9-bis(methoxymethyl)fluorene is 13% and the loading amount of 2,2′-dimethoxy-1,1′-binaphthyl is 2% and the total loading amount is 15%, the activity of the catalyst is 65 kgPP.Math.(g.Math.cat)″1, which is applicable to the production, with good comprehensive performance, select the total loading amount of 15% as the expected catalyst component. When preparing this catalyst component, the adding amounts of the two kinds of electron donors are the ratio to be determined.

(31) By adjusting the loading amounts of 9,9-bis(methoxymethyl)fluorene and 2,2′-dimethoxy-1,1′-binaphthyl within a small range of total loading amount of 15%, obtained the results in table 2.

(32) TABLE-US-00002 TABLE 2 The component design of compounding A with Bas internal electron donor, and the performances of catalyst components Expected Expected Catalyst bulk loading loading Loading Loading activity/ density iso- amount amount amount amount kgPP .Math. of PP/ tacticity of of of of (g .Math. gPP .Math. of A/wt % B/wt % A/wt % B/wt % cat).sup.−3 cm.sup.−3 PP/% 8.0 7.0 7.9 5.9 60 0.39 97.2 10.0 5.0 10.2 4.3 64 0.40 97.4 11.0 4.0 10.9 3.6 64 0.40 97.9 12.0 3.0 11.2 2.7 66 0.41 98.1 14.0 1.0 14.2 0.9 67 0.41 98.2 14.0 2.0 13.5 1.8 65 0.41 98.8 15.0 1.0 15.5 0.8 68 0.42 98.6

(33) As can be seen from table 2, when the loading amount of 9,9-bis(methoxymethyl)fluorene is 15.5% and the loading amount of 2,2′-dimethoxy-1,1′-binaphthyl is 0.8% and the total loading amount is 16.3%, the prepared catalyst component has the following performances: catalyst activity is 68 kgPP/g.Math.cat; isotacticity of polypropylene is 98.6%, bulk density of polypropylene is 0.42 gPP/cm.sup.3. In addition, the ethoxy content of this catalyst component measured is 0.8%, and this catalyst component is sensitive to hydrogen regulation, and the isotacticity of polypropylene is adjustable. Table 3 shows the carrier particle size distribution and catalyst component particle size distribution, and table 4 shows the polypropylene particle size distribution, and table 5 shows the polymer molecular weights and distributions. The morphology “duplication” phenomena of carrier, catalyst component and polypropylene are obvious.

(34) TABLE-US-00003 TABLE 3 Particle size distribution of carrier and catalyst component Particle size A/ B/ D.sub.10/ D.sub.50/ D.sub.90/ distribution Category wt % wt % μm μm μm index Catalyst 15.5 0.8 23.2 42.2 73.1 1.18 component Carrier — — 23.8 45.0 76.1 1.16

(35) TABLE-US-00004 TABLE 4 Particle size distribution of polypropylene A/ B/ Polymer screening result/mm, % wt % wt % >2.0 2.0-0.9 0.9-0.45 0.45-0.2 <0.2 15.5 0.8 37.3 57.1 4.8 0.6 0.2

(36) TABLE-US-00005 TABLE 5 Polymer molecular weight and distribution Number- Weight- molecular 1,3- 1,4- average average z-average weight ether/ ether molecular Molecular molecular distribution wt % wt % weight Weight weight index 15.5 0.8 47431 199427 494487 4.205

(37) These performances are significantly different from the performances of catalyst components prepared by 9,9-bis (methoxymethyl) fluorene and 2,2′-dimethoxy-1,1′-binaphthyl as electron donor separately, for example, the catalytic activity of catalyst component prepared by 9,9-bis(methoxymethyl)fluorene as internal electron donor is 130 kgPP-/g.Math.cat, and the catalytic activity of catalyst component prepared by 2,2′-dimethoxy-1,1′-binaphthyl as internal electron donor is 46 kgPP/g.Math.cat.

Embodiment 4

(38) Prepare catalyst component by the compound of 9,9-bis(methoxymethyl)fluorene and diisobutyl phthalate as internal electron donor:

(39) According to the operating procedure of Embodiment 3, compound of 9,9-bis(methoxymethyl)fluorene and diisobutyl phthalate is designed as internal electron donor to prepare catalyst component. Through experiments, obtained the expected catalyst component with activity of 65 kgPP.Math.(g.Math.cat).sup.−1, and then slightly adjusting to get the optimal catalyst component, which loads 11.0% of 9,9-bis(methoxymethyl)fluorene and 3.9% of diisobutyl phthalate.

(40) The steps for preparing the compound catalyst component are as follows: add 150 mL TiCl.sub.4 into a dry glass reactor with nitrogen protection and cool it down to −20° C., add 10 g magnesium chloride-ethanols complex compound carrier by stirring, slowly raise the temperature to 70° C. Add 9,9-bis(methoxymethyl)fluorene (0.53 mmol/g.Math.carrier), continue to raise the temperature to 110° C., and add diisobutyl phthalate (0.15 mmol/g.Math.carrier) and react 2 h by stirring; suction filtrate the product, and add 150 mL TiCl.sub.4 again, raise the temperature to 120° C. and react 1.5 h by stirring, suction filtrate the product, wash the filter cake five times by hexane at 60-65° C., and dry it under vacuum condition to get the catalyst component.

(41) The optimal catalyst component loads 10.9% of 9,9-bis(methoxymethyl)fluorene and 3.3% of diisobutyl phthalate; its catalytic activity is 60 kgPP/g.Math.cat, bulk density of polypropylene is 0.42 g/cm.sup.3, the isotacticity is 97.5%, and the melting index is 2.85 g/10 min.

Embodiment 5

(42) Prepare catalyst component by the compound of dibutyl phthalate (A) and diisobutyl phthalate (B) as internal electron donor:

(43) According to the operating procedure of Embodiment 3, compound of dibutyl phthalate and diisobutyl phthalate is designed as the internal electron donor to prepare the catalyst component, table 6 shows the results. FIG. 8 shows the load curves of di butyl phthalate and diisobutyl phthalate, and the two curves have no great difference.

(44) As shown in table 6, no matter for the loading amounts of A and B or the compound competition loading amounts of A and B, or the performances of catalyst components when A or B alone or A and B compounding as internal electron donor, it does not show the apparent advantages of dibutyl phthalate and diisobutyl phthalate compounding as internal electron donor to prepare catalyst component.

(45) TABLE-US-00006 TABLE 6 Results of dibutyl phthalate and diisobutyl phthalate compounding as internal electron donor to prepare catalyst component cata- bulk lyst den- Adding ac- iso- sity amount/mmol Loading tivity tacti- of Melt (g .Math. amount/ kgPP .Math. city PP/ index/ carrier).sup.−1 wt % (g .Math. of gPP .Math. gPP .Math. A B A + B A B A + B cat).sup.−1 PP/% cm.sup.−3 min.sup.−1 — 0.36 0.36 — 5.68 5.68 46.2 95.57 0.43 5.5 0.36 — 0.36 6.60 — 6.60 48.5 95.78 0.44 5.6 0.12 0.24 0.36 2.10 4.35 6.45 47.4 95.21 0.43 2.7 0.18 0.18 0.36 3.44 2.54 5.98 48.3 94.78 0.43 2.7

Embodiment 6

(46) Prepare catalyst component by directly reacting magnesium chloride, alcohols, internal electron donor and titanium tetrachloride:

(47) Taking 9,9-bis(methoxymethyl)fluorene and diisobutyl phthalate as internal electron donor compound as an example, the steps for preparing catalyst component are as follows:

(48) a) Preparation of Ethanols Complex Compound

(49) Add 5 g anhydrous MgCl.sub.2 and 30 mL decane and 23 mL 2-ethyl hexanol into the three-necked flask equipped with stirrer and thermometer which is sufficiently replaced with nitrogen gas, raise the temperature to 130° C. by stirring, and continue to react 2 h. Add 1.5 mL tetrabutyltitanate and 2 mL diisobutyl phthalate to 5 mL toluene beforehand, and react 0.5 h at room temperature to get complex compound solution. Add this toluene solution into the three-necked flask and continue to react 1 h at 130° C., cool it down to room temperature to form a stable ethanols complex compound solution.

(50) b) Preparation of the Catalyst Component

(51) Dropwise add the above prepared ethanols complex compound solution within 30 min into a reactor (containing 200 mL titanium tetrachloride and maintained at a temperature of −20° C.) equipped with stirrer and thermometer and sufficiently replaced with nitrogen gas. After dropwise add is completed, raise the temperature to 70° C., and add 0.5 g 9,9-bis(methoxymethyl)fluorene which dissolved in 10 mL toluene, continue to raise the temperature to 110° C., and add 1.0 mL diisobutyl phthalate and continue to react 2 h. After the liquid is filtered, add 200 mL titanium tetrachloride again and react 1.5 h at 110° C. Filter to obtain the resultant and wash it with trichloromethane for 60 min at 60° C., and then wash it with hexane until there is no free chloride ion in the filtrate, get the catalyst component after vacuum drying.

(52) The catalyst component was measured that it contains 9.5% of 9,9-bis(methoxymethyl)fluorene and 4.6% of diisobutyl phthalate.

(53) The catalyst activity measured by propylene polymerization is 56 kg PP/g.Math.cat, the bulk density of polymers is 0.42 g/cm.sup.3%, and the polymer isotacticity is 98.5%.