MAGNESIUM-BASED SOLID AND CATALYST COMPONENT HAVING MULTIMODAL PORE DISTRIBUTION, AND PREPARATION METHODS THEREFOR

Abstract

A magnesium-based solid, by means of determination based on a nitrogen adsorption method, has a multimodal pore distribution and a specific surface area of not less than 50 m.sup.2/g, and the pore size distribution of the solid is in a range of 1 nm to 300 nm. There is at least one peak within a pore size range of less than 10 nm, and there is at least another peak within a pore size range of not less than 10 nm. A catalyst is formed using the solid catalyst component is used for propylene polymerization.

Claims

1. A magnesium-based solid with a multimodal pore distribution, which comprises a magnesium halide as a carrier and titanium element, wherein, as determined by a nitrogen adsorption method, the magnesium-based solid has a specific surface area of not less than 50 m.sup.2/g and a pore size distribution in a range of from 1 nm to 300 nm, wherein there are at least one peak within the pore size range of less than 10 nm and at least one peak within the pore size range of not less than 10 nm; preferably, the peak within the pore size range of less than 10 nm has a most probable pore size of from 2 nm to 8 nm, and preferably from 2 nm to 6 nm, and the peak within the pore size range of not less than 10 nm has a most probable pore size of from 15 nm to 200 nm, preferably from 20 nm to 100 nm, and more preferably from 30 nm to 90 nm.

2. The magnesium-based solid as claimed in claim 1, characterized in that in the magnesium-based solid, the ratio of the pore volume of pores with a pore size of less than 10 nm to the pore volume of pores with a pore size of not less than 10 nm is (0.1-20):1, and preferably (0.25-15):1.

3. The magnesium-based solid as claimed in claim 1, characterized in that the pore volume of pores with a pore size of less than 5 nm accounts for 10% to 90% of the total pore volume, and preferably 15% to 70%; and the pore volume of pores with a pore size of not less than 30 nm accounts for 5% to 70% of the total pore volume, and preferably 10% to 60%.

4. A method for preparing the magnesium-based solid as claimed in claim 1, comprising: S1. contacting a magnesium halide with a Lewis base in an organic solvent to form a magnesium-containing solution; S2. contacting the magnesium-containing solution with an inert dispersion medium and a Lewis acid to form a mixture; S3. in the presence of an auxiliary precipitant and a surfactant, precipitating the magnesium-based solid from the mixture, wherein, in step S1, the Lewis base includes an organic phosphorus compound, which is used in an amount of from 1.5 to 10 moles, preferably from 2 to 5 moles, per mole of the magnesium halide; more preferably, the Lewis base further includes an organic epoxy compound; and in step S2, the Lewis acid includes a titanium compound.

5. The method as claimed in claim 4, characterized in that in step S1, the magnesium halide is represented by a general formula (1):
MgX.sup.1.sub.2  (1), wherein X.sup.1 is a halogen, preferably chlorine, bromine or iodine, preferably the magnesium halide is magnesium dichloride; and/or the organic phosphorus compound is one or more of the compounds represented by formula (2) or formula (3): ##STR00002## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6 each independently have 1-20 carbon atoms and are selected from the group consisting of linear or branched alkyl groups, cycloalkyl groups, aromatic hydrocarbon groups, and aromatic hydrocarbon groups having a substituent, preferably the organic phosphorus compound is one or more of trimethyl phosphate, triethyl phosphate, tributyl phosphate, tripentyl phosphate, triphenyl phosphate, trimethyl phosphite, triethyl phosphite, tributyl phosphite and tribenzyl phosphite; and/or the organic solvent is one or more selected from the group consisting of aromatic hydrocarbon compounds and halogenated hydrocarbon compounds, preferably the organic solvent is one or more of toluene, ethylbenzene, benzene, xylenes and chlorobenzene, and more preferably the organic solvent is used in an amount of from 1 to 40 moles, and preferably from 2 to 30 moles, relative to one mole of the magnesium halide.

6. The method as claimed in claim 4, characterized in that, in step S2, the inert dispersion medium is one or more selected from the group consisting of kerosenes, paraffin oils, white oils, vaseline oils, methyl silicone oils, aliphatic and cycloaliphatic hydrocarbons, preferably the inert dispersion medium is one or more of white oils, hexanes and decanes, and more preferably the inert dispersion medium is used in an amount of from 0.1 g to 300 g, preferably from 1 g to 150 g, relative to one gram of the magnesium halide; and/or the Lewis acid comprises a titanium-containing compound represented by general formula (4):
TiX.sup.2.sub.m(OR.sup.1).sub.4-m  (4) wherein X.sup.2 is a halogen, preferably chlorine, bromine or iodine, le is a hydrocarbon group having 1-20 carbon atoms, and m is an integer of 1 to 4, preferably the titanium-containing compound is one or more of titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, titanium tetrabutoxide, titanium tetraethoxide, triethoxy titanium chloride, diethoxy titanium dichloride and ethoxy titanium trichloride, and more preferably the titanium-containing compound is used in an amount of from 0.5 to 25 moles, preferably from 1 to 20 moles, relative to one mole of the magnesium halide.

7. The method as claimed in claim 4, characterized in that, in step S3, the auxiliary precipitant is one or more selected from the group consisting of organic acids, organic acid anhydrides, organic ethers and organic ketones, preferably the auxiliary precipitant is one or more selected from the group consisting of acetic anhydride, phthalic anhydride, succinic anhydride, maleic anhydride, pyromellitic dianhydride, acetic acid, propionic acid, butyric acid, acrylic acid, methacrylic acid, acetone, methyl ethyl ketone, benzophenone, dimethyl ether, diethyl ether, dipropyl ether, dibutyl ether and dipentyl ether, and more preferably the auxiliary precipitant is used in an amount of from 0.01 to 1 mole, preferably from 0.04 to 0.4 moles, relative to one mole of the magnesium halide; and/or the surfactant is a polymeric surfactant, preferably the surfactant is one or more selected from the group consisting of alkyl (meth)acrylate polymers, alkyl (meth)acrylate copolymers, alcoholysates of maleic anhydride polymers, and alcoholysates of maleic anhydride copolymers, and more preferably the surfactant is used in an amount of from 0.01 g to 5 g, preferably from 0.05 g to 1 g, relative to one gram of the magnesium halide.

8. A solid catalyst component for olefin polymerization with a multimodal pore distribution, which comprises the magnesium-based solid as claimed in claim 1 and at least one internal electron donor.

9. The solid catalyst component as claimed in claim 8, characterized in that, as measured by nitrogen adsorption method, the solid catalyst component has a pore size distribution exhibiting multiple peaks and a specific surface area of not less than 50 m.sup.2/g; wherein the pore size distribution exhibiting multiple peaks of the solid is such that there are at least a first peak in the pore size range of 1 nm-10 nm and at least a second peak in the pore size range of 10 nm-200 nm.

10. The solid catalyst component as claimed in claim 8, characterized in that, the pore size distribution exhibiting multiple peaks of the solid is such that the peak in the pore size range of 1 nm-10 nm has a most probable pore size of from 2 nm to 8 nm, and further preferably from 2 nm to 6 nm; and the peak in the pore size range of 10 nm-200 nm has a most probable pore size of from 15 nm to 200 nm, preferably from 20 nm to 100 nm, and more preferably from 30 nm to 90 nm.

11. The solid catalyst component as claimed in claim 8, characterized in that, the pore volume of pores with a pore size of less than 5 nm accounts for 10% to 90%, preferably 15% to 70% of the total pore volume; and the pore volume of pores with a pore size of not less than 30 nm accounts for 5% to 70%, preferably 10% to 60% of the total pore volume.

12. The solid catalyst component as claimed in claim 8, wherein the internal electron donor is one or more selected from the group consisting of esters, ethers, ketones, amines, and silanes, preferably at least one of aliphatic mono- or poly-carboxylic acid esters, aromatic carboxylic acid esters, diol ester compounds and diether compounds, and preferably includes at least one of dibasic aliphatic carboxylic acid esters, aromatic carboxylic acid esters, diol esters and diether compounds, and more preferably includes at least one of phthalates, malonates, succinates, glutarates, diol esters, diethers, neovalerates and carbonates.

13. A method for preparing the solid catalyst component for olefin polymerization as claimed in claim 8, comprising adding at least one internal electron donor during the preparation of the magnesium-based solid; or/and contacting at least one internal electron donor with the magnesium-based solid, to obtain the solid catalyst component for olefin polymerization.

14. A catalyst system for olefin polymerization, comprising (1) the solid catalyst component as claimed in claim 8; (2) an alkyl aluminum compound; and (3) optionally, an external electron donor.

15. A method for olefin polymerization, comprising polymerizing an olefin monomer in the presence of the solid catalyst component as claimed in claim 8.

16. A method for olefin polymerization, comprising polymerizing an olefin monomer in the presence of the catalyst system as claimed in claim 14.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0107] FIG. 1 shows the pore size distribution diagram of the magnesium-based solid prepared in Example 1, measured by nitrogen adsorption method and calculated by NLDFT algorithm.

[0108] FIG. 2 shows the pore size distribution diagram of the magnesium-based solid prepared in Example 2, measured by nitrogen adsorption method and calculated by NLDFT algorithm.

[0109] FIG. 3 shows the pore size distribution diagram of the magnesium-based solid prepared in Example 3, measured by nitrogen adsorption method and calculated by NLDFT algorithm.

[0110] FIG. 4 shows the pore size distribution diagram of the magnesium-based solid prepared in Comparative Example 1, measured by nitrogen adsorption method and calculated by NLDFT algorithm.

[0111] FIG. 5 shows the pore size distribution diagram of the catalyst component prepared in Example 7, measured by nitrogen adsorption method and calculated by NLDFT algorithm.

[0112] FIG. 6 shows the pore size distribution diagram of the catalyst component prepared in Comparative Example 5, measured by nitrogen adsorption method and calculated by NLDFT algorithm.

[0113] FIG. 7 shows a microscope image of the magnesium-based solid prepared in Example 1.

EXAMPLES

[0114] The present invention will be illustrated in detail below by way of examples, but the protection scope of the present invention is not limited to the following description.

[0115] If the specific conditions are not indicated in the examples, it is carried out according to the conventional conditions or the conditions suggested by the manufacturer. The reagents or instruments used without the manufacturer's indication are conventional products that can be obtained through commercial channels.

[0116] In the following examples, the test methods involved are as follows: [0117] 1. Determination of titanium content in catalyst: colorimetric determined by using UV-Vis spectrophotometer model 722. [0118] 2. Determination of magnesium content in catalyst: measured by complexometric titration between magnesium ion and EDTA. [0119] 3. Particle size distribution of magnesium-containing carrier or catalyst: measured by laser diffraction method, using Malvern 2000 particle size analyzer and n-hexane as a dispersant. [0120] 4. Determination of the content of the internal electron donor compound in catalyst: after the catalyst dry powder is decomposed by a dilute acid (such as dilute sulfuric acid, etc.), the internal electron donor compound is extracted with an extractant (such as hexane, etc.) and then determined by chromatography, with an ether-type electron donor being determined by using Agilent 6890N gas chromatograph, and an ester-type electron donor being determined by using Waters 600E high performance liquid chromatography. [0121] 5. Specific surface area and pore size distribution of magnesium-containing carrier or catalyst: determined by nitrogen adsorption method with ASAP 2460 specific surface area and porosity analyzer from Micromeritics, USA. [0122] 6. Determination of polymer bulk density (BD): according to ASTM D1895-96 standard. [0123] 7. Isotacticity index (II) of propylene polymer: determined by heptane extraction method carried out as follows: 2 grams of dry polymer sample were extracted with boiling heptane in an extractor for 6 hours, then the residual substance was dried to constant weight, and the ratio of the weight of the residual polymer (g) to 2 (g) was regarded as isotacticity. [0124] 8. Molecular weight distribution MWD (MWD=Mw/Mn) of polymer: determined by using PL-GPC220 with trichlorobenzene as solvent at 150° C. (standards: polystyrene, flow rate: 1.0 ml/min, columns: 3×Plgel 101.tm M1xED-B 300×7.5 nm). [0125] 9. Melt flow index (MI) of polymer: determined by using MI-4 melt flow index instrument from GOTTFERT company, German, according to the GB/T 3682.1-2018 standard.

[0126] The examples given below are intended to illustrate the present invention, but not to limit the present invention.

Example 1

[0127] Example 1 is used to illustrate the preparation of a magnesium-based solid.

[0128] To a reactor, in which air had been repeatedly replaced with high-purity nitrogen, 10.86 g of anhydrous magnesium chloride, 249 mL of toluene, 10.75 g of epichlorohydrin, and 70.7 g of tributyl phosphate were successively added, and the contents were maintained at 60° C. under the stirring of 300 rpm for 2 hours. Then, 2.56 g of phthalic anhydride was added, and the contents were maintained at 60° C. for an additional hour. The solution was cooled to 14° C. In advance, 2.1 g of surfactant (an alcoholysate of maleic anhydride-methacrylate copolymer, which is commercially available from Guangzhou Ruishengyan Chemical Technology Co., Ltd. under the tradename T632) and 220 ml of food-grade No. 100 white oil (having a kinematic viscosity at 40° C. of 100 mm.sup.2/s) were mixed uniformly to form mixture A. 151 ml of titanium tetrachloride and the mixture A were simultaneously added dropwise thereto over 40 min. After the dropwise addition was completed, the contents were stirred at 400 rpm for 1 hour. The temperature was then gradually increased to 80° C. over 3 hours, and the mother liquor was then filtered off. The residual solids were washed twice with hot toluene, then twice with hexane, and dried to obtain a titanium-containing, magnesium-based solid. The obtained solid had an average particle diameter D50 of 34.2 μm, a SPAN value (i.e., (D90−D10)/D50) of 0.60, a titanium content of 2.0% by weight, and a Mg content of 20.3% by weight. A micrograph of the solid is shown in FIG. 7.

[0129] The pore size distribution diagram of the solid, measured by nitrogen adsorption method and calculated by the NLDFT algorithm, is shown in FIG. 1. It can be seen from FIG. 1 that the pore size distribution is shown as a multimodal pore size distribution, including at least one peak in a pore size range below 10 nm and at least another peak in a pore size range of not less than 10 nm.

[0130] The pore size data of the solid measured by nitrogen adsorption method are given in Table 1.

Example 2

[0131] Example 2 is used to illustrate the preparation of a magnesium-based solid.

[0132] To a reactor, in which air had been repeatedly replaced with high-purity nitrogen, 10.86 g of anhydrous magnesium chloride, 194 mL of toluene, 10.75 g of epichlorohydrin, and 75.12 g of tributyl phosphate were successively added, and the contents were maintained at 60° C. with stirring for 2 hours. Then, 3.2 g of phthalic anhydride was added, and the contents were maintained at 60° C. for an additional hour. The solution was cooled to 24° C., and 2.5 g of surfactant (an alcoholysate of maleic anhydride-methacrylate copolymer, which is commercially available from Guangzhou Ruishengyan Chemical Technology Co., Ltd. under the tradename T632) diluted in 40 ml of toluene was then added thereto. The contents were continuously stirred for 1 hour, and 136 ml of titanium tetrachloride and 240 ml of food-grade No. 100 white oil (having a kinematic viscosity at 40° C. of 100 mm.sup.2/s) were then simultaneously added dropwise thereto over 40 min. After the dropwise addition was completed, the contents were stirred at 400 rpm for 1 hour. The temperature was then gradually increased to 80° C., and the mother liquor was then filtered off. The residual solids were washed twice with hot toluene, then twice with hexane, and dried to obtain a titanium-containing, magnesium-based solid. The obtained solid had an average particle diameter D50 of 62.1 μm, a SPAN value of 0.63, a titanium content of 2.3% by weight, and a Mg content of 21.1% by weight.

[0133] The pore size distribution diagram of the solid, measured by nitrogen adsorption method and calculated by the NLDFT algorithm, is shown in FIG. 2. It can be seen from FIG. 2 that the pore size distribution is shown as a multimodal pore size distribution, including at least one peak in a pore size range below 10 nm and at least another peak in a pore size range of not less than 10 nm.

[0134] The pore size data of the solid measured by nitrogen adsorption method are given in Table 1.

Example 3

[0135] A magnesium-based solid was prepared by the method described in Example 1, except that the amount of the epichlorohydrin used was changed to 14.2 g, the amount of the tributyl phosphate used was changed to 53.2 g, the amount of the toluene used was changed to 197 ml, and the amount of the titanium tetrachloride used was changed to 133 ml, and that after the addition of the phthalic anhydride and the maintaining at 60° C. for an additional hour, the solution was cooled to 8° C. The resulting solid had a titanium content of 2.1% by weight and a Mg content of 21.2% by weight.

[0136] The pore size distribution diagram of the solid, measured by nitrogen adsorption method and calculated by the NLDFT algorithm, is shown in FIG. 3. It can be seen from FIG. 3 that the pore size distribution is shown as a multimodal pore size distribution, including at least one peak in a pore size range below 10 nm and at least another peak in a pore size range of not less than 10 nm.

[0137] The pore size data of the solid measured by nitrogen adsorption method are given in Table 1.

Example 4

[0138] A magnesium-based solid was prepared by the method described in Example 1, except that the amount of the epichlorohydrin used was changed to 7.2 g and the amount of the tributyl phosphate used was changed to 65.1 g, that the addition of the tributyl phosphate was followed by the addition of 2.2 g of ethanol, that the amount of the white oil used was changed to 184 ml and the amount of the titanium tetrachloride used was changed to 203 ml, and that after the addition of the phthalic anhydride and the maintaining at 60° C. for an additional hour, the solution was cooled to 0° C. The resulting solid had a titanium content of 3.6% by weight and a Mg content of 20.2% by weight.

[0139] The pore size data of the solid measured by nitrogen adsorption method are given in Table 1, and the pore size distribution is a multimodal pore size distribution.

Example 5

[0140] A titanium-containing, magnesium-based solid was prepared by the method described in Example 1, except that the amount of the epichlorohydrin used was 10.75 g, the amount of the tributyl phosphate used was changed to 33.2 g, the amount of the toluene used was changed to 72 ml, the amount of the white oil used was changed to 120 ml, and the amount of the titanium tetrachloride used was changed to 112 ml, and that after the addition of the phthalic anhydride and the maintaining at 60° C. for an additional hour, the solution was cooled to 0° C. The resulting solid had a titanium content of 2.6% by weight and a Mg content of 21.4% by weight.

[0141] The pore size data of the solid measured by nitrogen adsorption method are given in Table 1, and the pore size distribution is a unimodal pore size distribution.

Comparative Example 1

[0142] A solid was prepared by the preparation method described in Example 1 in patent CN107207657A, except that the surfactant VISCOPLEX was changed to the surfactant used in Example 1 of the present invention. The obtained solid had an average particle diameter D50 of 27.1 a SPAN value of 1.24, a titanium content of 2.1% by weight, and a Mg content of 20.2% by weight.

[0143] The pore size data of the solid measured by nitrogen adsorption method are given in Table 1, and the pore size distribution diagram is shown in FIG. 4, which is a unimodal pore size distribution. FIG. 4 is a pore size distribution diagram using the NLDFT algorithm.

Comparative Example 2

[0144] A solid was prepared by the preparation method described in Example 1 in patent CN1097597C, except that the electron donor diisobutyl phthalate was not added and the subsequent steps were conducted as follows: after the precipitation of the solids, the mother liquor was filtered off, and the solids were washed with hot toluene twice, then with hexane twice, and dried to obtain a titanium-containing, magnesium-based solid. The obtained solid had an average particle diameter D50 of 24.1 μm, a SPAN value of 1.14, a titanium content of 2.3% by weight, and a Mg content of 21.1% by weight.

[0145] The pore size data of the solid measured by nitrogen adsorption method are given in Table 1, and the pore size distribution is a unimodal pore size distribution.

TABLE-US-00001 TABLE 1 NLDFT algorithm Ratio of the The most The most pore volume probable probable with a pore pore size of pore size of Proportion Proportion size <10 nm Catalyst the peak in the peak in of the pore of the pore to the pore Specific pore size the pore size the pore size volume with volume with volume with surface Pore distribution range of less range of at a pore a pore a pore area volume Item profile than 10 nm, nm least 10 nm, nm size <5 nm size ≥30 nm size ≥10 nm (m.sup.2/g) (cm.sup.3/g) Ex. 1 multimodal 3.2 86.2 0.652 0.144 4.81 205.59 0.218 Ex. 2 multimodal 2.9 68.5 0.174 0.536 0.37 165.13 0.413 Ex. 3 multimodal 1.6 34.3 0.555 0.291 1.58 227.79 0.274 Ex. 4 multimodal 4.6 73.9 0.738 0.056 8.02 243.39 0.179 Ex. 5 unimodal 2.7 no peak 0.655 0.028 20.62 229.36 0.18 Comp. Ex. 1 unimodal 4.3 no peak 0.663 0.02 35.71 184.86 0.182 Comp. Ex. 2 unimodal 5 no peak 0.529 0.002 38.42 144.6 0.172 Notation: Under the NLDFT algorithm, the proportion of the pore volume with a pore size <5 nm refers to the ratio of the pore volume with a pore size <5 nm obtained by the NLDFT algorithm to the total pore volume calculated under this algorithm, and the other representations have analogical meanings. The pore volumes given in Table 1 are the BJH algorithm pore volume.

Example 6

[0146] A. Preparation of Solid Catalyst Component

[0147] To a reactor, in which air had been repeatedly replaced with high-purity nitrogen, 10.86 g of anhydrous magnesium chloride, 249 mL of toluene, 10.75 g of epichlorohydrin, and 70.7 g of tributyl phosphate were successively added, and the contents were maintained at 60° C. under the stirring of 300 rpm for 2 hours. Then, 2.5 g of phthalic anhydride was added, and the contents were maintained at 60° C. for an additional hour. The solution was cooled to 15° C. In advance, 2.1 g of surfactant (an alcoholysate of maleic anhydride-methacrylate copolymer, which is commercially available from Guangzhou Ruishengyan Chemical Technology Co., Ltd. under the tradename T632) and 220 ml of food-grade No. 100 white oil (having a kinematic viscosity at 40° C. of 100 mm.sup.2/s) were mixed uniformly to form mixture 1. 151 ml of titanium tetrachloride and the mixture 1 were simultaneously added dropwise thereto over 40 min. After the dropwise addition was completed, the contents were stirred at 400 rpm for 1 hour. The temperature was then gradually increased to 80° C. over 3 hours, 3 mL of di-n-butyl phthalate as an electron donor was then added thereto, and the temperature was raised to 85° C. and then kept constant for 1 hour. After filtration, the residual solids were washed twice with hot toluene. Next, 80 mL of titanium tetrachloride and 120 mL of toluene were added thereto, and the contents were maintained at a constant temperature of 110° C. for 0.5 hours and then filtered, and the operation was repeated once. Then, the obtained solids were washed 5 times with hexane and then dried under vacuum to obtain a solid catalyst component for olefin polymerization. The data of the catalyst component are given in Table 3.

[0148] The pore size data of the solids measured by nitrogen adsorption method are given in Table 2. The pore size distribution of the catalyst is a multimodal pore size distribution.

[0149] B. Propylene Polymerization

[0150] At room temperature, to a 5-liter autoclave, in which the atmosphere had been fully replaced by nitrogen, were charged with 5 mL of a solution of triethylaluminum in hexane (having a triethylaluminum concentration of 0.5 mmol/mL), 1 mL of a solution of cyclohexylmethyldimethoxysilane (CHMMS) in hexane (having a CHMMS concentration of 0.1 mmol/mL), 10 mL of anhydrous hexane and 10 mg of the catalyst component from Example 6. One liter of hydrogen in standard state and 1.15 kg of liquid propylene were introduced thereinto. The temperature was raised to 70° C., and the polymerization was carried out at 70° C. for 1 hour. After the reaction was completed, the autoclave was cooled and the stirring was stopped, and then the reaction product was discharged to obtain an olefin polymer. The polymerization results of the catalyst and the polymer data are given in Table 3.

Example 7

[0151] A. Preparation of Solid Catalyst Component

[0152] To a reactor, in which air had been repeatedly replaced with high-purity nitrogen, 10.86 g of anhydrous magnesium chloride, 272 mL of toluene, 9.76 g of epichlorohydrin, and 78 g of tributyl phosphate were successively added, and the contents were maintained at 60° C. under the stirring of 300 rpm for 2 hours. Then, 3 g of phthalic anhydride was added, and the contents were maintained at 60° C. for an additional hour. The solution was cooled to 10° C. In advance, 3.2 g of surfactant (an alcoholysate of maleic anhydride-methacrylate copolymer, which is commercially available from Guangzhou Ruishengyan Chemical Technology Co., Ltd. under the tradename T632) and 240 ml of food-grade No. 100 white oil (having a kinematic viscosity at 40° C. of 100 mm.sup.2/s) were mixed uniformly to form mixture 1. 135 ml of titanium tetrachloride and the mixture 1 were simultaneously added dropwise thereto over 40 min. After the dropwise addition was completed, the contents were stirred at 400 rpm for 2 hours. The temperature was then gradually increased to 85° C. over 3 hours, with 3 mL of 2,4-pentanediol dibenzoate as an electron donor being added during the temperature increasing, and the temperature was then kept constant at 85° C. for 1 hour. After filtration, the residual solids were washed twice with hot toluene. Next, 80 mL of titanium tetrachloride and 120 mL of toluene were added thereto, and the contents were maintained at a constant temperature of 110° C. for 0.5 hours and then filtered, and the operation was repeated once. Then, the obtained solids were washed 5 times with hexane and then dried under vacuum to obtain a solid catalyst component for olefin polymerization. The data of the catalyst component are given in Table 3.

[0153] The pore size distribution diagram of the solid, measured by nitrogen adsorption method and calculated by the NLDFT algorithm, is shown in FIG. 5. It can be seen from FIG. 5 that the pore size distribution is shown as a multimodal pore size distribution, including at least one peak in a pore size range below 10 nm and at least another peak in a pore size range of not less than 10 nm. The pore size data of the solids measured by nitrogen adsorption method are given in Table 2.

[0154] B. Propylene Polymerization

[0155] Propylene polymerization method was the same as described for Example 6, and the polymerization data of the catalyst and the polymer data are given in Table 3.

Example 8

[0156] A. Preparation of Solid Catalyst Component

[0157] To a reactor, in which air had been repeatedly replaced with high-purity nitrogen, 10.86 g of anhydrous magnesium chloride, 211 mL of toluene, 11.5 g of epichlorohydrin, and 68 g of tributyl phosphate were successively added, and the contents were maintained at 60° C. with stirring for 2 hours. Then, 2.5 g of phthalic anhydride was added, and the contents were maintained at 60° C. for an additional hour. The solution was cooled to 0° C., 3 g of 9,9-dimethoxymethylfluorene was added thereto, and the contents were continuously stirred for 60 min. In advance, 2.5 g of surfactant (an alcoholysate of maleic anhydride-methacrylate copolymer, which is commercially available from Guangzhou Ruishengyan Chemical Technology Co., Ltd. under the tradename T632) and 260 ml of food-grade No. 100 white oil (having a kinematic viscosity at 40° C. of 100 mm.sup.2/s) were mixed uniformly to form mixture 1. 165 ml of titanium tetrachloride and the mixture 1 were simultaneously added dropwise thereto over 40 min. After the dropwise addition was completed, the contents were stirred at 400 rpm for 1 hour. The temperature was then gradually increased to 85° C. over 4 hours and then kept constant for 1 hour. After filtration, the residual solids were washed twice with hot toluene. Next, 80 mL of titanium tetrachloride and 120 mL of toluene were added thereto, and the contents were maintained at a constant temperature of 110° C. for 0.5 hours and then filtered, and the operation was repeated once. Then, the obtained solids were washed 5 times with hexane and then dried under vacuum to obtain a solid catalyst component for olefin polymerization. The data of the catalyst component are given in Table 3.

[0158] The pore size data of the solids measured by nitrogen adsorption method are given in Table 2. The pore size distribution of the catalyst is a multimodal pore size distribution.

[0159] B. Propylene Polymerization

[0160] Propylene polymerization method was the same as described for Example 6, and the polymerization data of the catalyst and the polymer data are given in Table 3.

Example 9

[0161] A. Preparation of Solid Catalyst Component

[0162] The procedure was substantially the same as Example 6, except that the amount of the epichlorohydrin was changed to 14.2 g, the amount of the tributyl phosphate was changed to 53.2 g, the amount of the toluene was changed to 197 ml, and the amount of the titanium tetrachloride was changed to 133 ml, and that after the addition of the phthalic anhydride and the maintaining at 60° C. for an additional hour, the solution was cooled to 8° C. Catalyst component data are given in Table 3.

[0163] The pore size data of the catalyst measured by nitrogen adsorption method are given in Table 2. The pore size distribution of the catalyst is a multimodal pore size distribution.

[0164] B. Propylene Polymerization

[0165] Propylene polymerization method was the same as described for Example 6, and the polymerization data of the catalyst and the polymer data are given in Table 3.

Example 10

[0166] A. Preparation of Solid Catalyst Component

[0167] The procedure was substantially the same as Example 6, except that the amount of the epichlorohydrin used was changed to 7.2 g and the amount of the tributyl phosphate used was changed to 65.1 g, that the addition of the tributyl phosphate was followed by the addition of 2.2 g of ethanol, that the amount of the white oil used was changed to 184 ml and the amount of the titanium tetrachloride used was changed to 203 ml, and that after the addition of the phthalic anhydride and the maintaining at 60° C. for an additional hour, the solution was cooled to 0° C. Catalyst component data are given in Table 3.

[0168] The pore size data of the solids measured by nitrogen adsorption method are given in Table 2. The pore size distribution of the catalyst is a multimodal pore size distribution.

[0169] B. Propylene Polymerization

[0170] Propylene polymerization method was the same as described for Example 6, and the polymerization data of the catalyst and the polymer data are given in Table 3.

Example 11

[0171] A. Preparation of Solid Catalyst Component

[0172] To a reactor, in which air had been repeatedly replaced with high-purity nitrogen, were successively charged with 10.86 g of anhydrous magnesium chloride, 104 g of toluene, 10.5 g of epichlorohydrin, 70.0 g of tributyl phosphate, and 1.5 mL of ethylene glycol dibutyl ether, and the contents were maintained at 60° C. with stirring of 300 rpm for 2 hours. Then, 3.4 g of phthalic anhydride was added, and the contents were continuously stirred at 60° C. for an additional hour. The solution was cooled to 14° C., and the stirring speed was increased to 400 rpm. In advance, 128.5 g of food-grade No. 100 white oil (having a kinematic viscosity at 40° C. of 100 mm.sup.2/s) and 5.7 g of surfactant (T602, commercially available from Guangzhou Ruishengyan Chemical Technology Co., Ltd.) were mixed to form mixture 1. 181.7 ml of titanium tetrachloride and the mixture 1 were simultaneously added dropwise thereto over 60 min. After the dropwise addition was completed, the contents were maintained for 1 hour to obtain mixture 2. The temperature was gradually increased to 80° C., 2.0 mL of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane was added, and the temperature was raised to 85° C. and maintained for 1 hour. After filtering off the supernatant, the residual solids were washed three times with 200 mL of toluene. Next, the solids were treated with 120 mL of toluene and 80 mL of titanium tetrachloride at 90° C. for 1 hour, and then the liquid was filtered off. Then, the solids were treated with 120 mL of toluene and 80 mL of titanium tetrachloride at 110° C. for 1 hour, and then the liquid was filtered off. Next, the solids were washed 4 times with 200 mL of hexane, to afford a solid catalyst component for olefin polymerization. The catalyst physical property data are given in Table 3, and the catalyst pore size data are given in Table 2.

[0173] B. Propylene Polymerization

[0174] Propylene polymerization method was the same as described for Example 6, and the polymerization data of the catalyst and the polymer data are given in Table 3.

Example 12

[0175] A. Preparation of Solid Catalyst Component

[0176] To a reactor, in which air had been repeatedly replaced with high-purity nitrogen, were successively charged with 10.86 g of anhydrous magnesium chloride, 104 g of toluene, 7.2 g of epichlorohydrin, 75.2 g of tributyl phosphate, and 1.5 mL of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane, and the contents were maintained at 60° C. with stirring of 300 rpm for 2 hours. Then, 4.59 g of phthalic anhydride was added, and the contents were maintained at 60° C. for an additional hour. The solution was cooled to 14° C., and the stirring speed was increased to 400 rpm. In advance, 128.5 g of food-grade No. 100 white oil (having a kinematic viscosity at 40° C. of 100 mm.sup.2/s) and 5.7 g of surfactant (T602, commercially available from Guangzhou Ruishengyan Chemical Technology Co., Ltd.) were mixed to form mixture 1. 81.7 ml of titanium tetrachloride and the mixture 1 were simultaneously added dropwise thereto over 60 min. After the dropwise addition was completed, the contents were maintained for 1 hour. The temperature was gradually increased to 80° C. and maintained for 1 hour. After filtering off the supernatant, the residual solids were washed two times with 200 mL of toluene. Next, 160 mL of toluene, 40 mL of titanium tetrachloride and 2.6 mL of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were added, and the temperature was raised to 85° C. and maintained for 2 hours. After filtering off the liquid, the solids were treated with 120 mL of toluene and 80 mL of titanium tetrachloride at 90° C. for 1 hour, and then the liquid was filtered off. Then, the solids were treated with 120 mL of toluene and 80 mL of titanium tetrachloride at 110° C. for 1 hour, and then the liquid was filtered off. Next, the solids were washed 5 times with 200 mL of hexane, to afford a solid catalyst component for olefin polymerization. The catalyst physical property data are given in Table 3, and the catalyst pore size data are given in Table 2.

[0177] B. Propylene Polymerization

[0178] Propylene polymerization method was the same as described for Example 6, and the polymerization data of the catalyst and the polymer data are given in Table 3.

Example 13

[0179] A. Preparation of Solid Catalyst Component

[0180] To a reactor, in which air had been repeatedly replaced with high-purity nitrogen, were successively charged with 10.86 g of anhydrous magnesium chloride, 104 g of toluene, 12.43 g of epichlorohydrin, and 75.2 g of tributyl phosphate, and the contents were maintained at 60° C. with stirring of 300 rpm for 2 hours. Then, 4.59 g of phthalic anhydride was added, and the contents were maintained at 60° C. for an additional hour. The solution was cooled to 14° C., and the stirring speed was increased to 400 rpm. In advance, 128.5 g of food-grade No. 100 white oil (having a kinematic viscosity at 40° C. of 100 mm.sup.2/s) and 5.7 g of surfactant (T602, commercially available from Guangzhou Ruishengyan Chemical Technology Co., Ltd.) were mixed to form mixture 1. 81.7 ml of titanium tetrachloride and the mixture 1 were simultaneously added dropwise thereto over 60 min. After the dropwise addition was completed, the contents were maintained for 1 hour. The temperature was gradually increased to 80° C. and maintained for 1 hour. After filtering off the supernatant, the residual solids were washed two times with 200 mL of toluene. Next, 160 mL of toluene, 40 mL of titanium tetrachloride and 3.6 mL of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane were added, and the temperature was raised to 85° C. and maintained for 2 hours. After filtering off the liquid, the solids were treated with 120 mL of toluene and 80 mL of titanium tetrachloride at 90° C. for 1 hour, and then the liquid was filtered off. Then, the solids were treated with 120 mL of toluene and 80 mL of titanium tetrachloride at 110° C. for 1 hour, and then the liquid was filtered off. Next, the solids were washed 5 times with 200 mL of hexane, to afford a solid catalyst component for olefin polymerization. The catalyst physical property data are given in Table 3, and the catalyst pore size data are given in Table 2.

[0181] B. Propylene Polymerization

[0182] Propylene polymerization method was the same as described for Example 6, and the polymerization data of the catalyst and the polymer data are given in Table 3.

Comparative Example 3

[0183] A. Preparation of Solid Catalyst Component

[0184] The procedure was substantially the same as Example 6, except that the amount of the epichlorohydrin used was 10.75 g, the amount of the tributyl phosphate used was changed to 33.2 g, the amount of the toluene used was changed to 72 ml, the amount of the white oil used was changed to 120 ml, and the amount of the titanium tetrachloride used was changed to 112 ml, and that after the addition of the phthalic anhydride and the maintaining at 60° C. for an additional hour, the solution was cooled to 0° C. Catalyst component data are given in Table 3.

[0185] The pore size data of the catalyst measured by nitrogen adsorption method are given in Table 2. The pore size distribution of the catalyst is a unimodal pore size distribution.

[0186] B. Propylene Polymerization

[0187] Propylene polymerization method was the same as described for Example 6, and the polymerization data of the catalyst and the polymer data are given in Table 3.

Comparative Example 4

[0188] A. Preparation of Solid Catalyst Component

[0189] The procedure was substantially the same as Example 6, except that the amount of the tributyl phosphate used was changed to 38.8 g. Catalyst component data are given in Table 3.

[0190] The pore size data of the catalyst measured by nitrogen adsorption method are given in Table 2. The pore size distribution of the catalyst is a unimodal pore size distribution.

[0191] B. Propylene Polymerization

[0192] Propylene polymerization method was the same as described for Example 6, and the polymerization data of the catalyst and the polymer data are given in Table 3.

Comparative Example 5

[0193] A solid was prepared by the preparation method described in Example 1 in patent CN107207657A, except that the surfactant VISCOPLEX was changed to the surfactant used in Example 1. The solid was then maintained, together with 260 ml of a 20% titanium tetrachloride solution in toluene and 3 ml of di-n-butyl phthalate electron donor, at 85° C. for 1 hour. After filtering, the solids were washed twice with toluene. Then, 100 ml of titanium tetrachloride and 150 ml of toluene were added thereto, the temperature was maintained constant at 110° C. for 0.5 hours, and then the liquid was filtered off. This operation was repeated once. Then, the obtained solids were washed 5 times with hexane and then vacuum-dried to obtain a solid catalyst component for olefin polymerization. Catalyst component data are given in Table 3.

[0194] The pore size distribution diagram of the solids, measured by nitrogen adsorption method and calculated by the NLDFT algorithm, is shown in FIG. 6.

[0195] The pore size data of the catalyst measured by nitrogen adsorption method are given in Table 2. The pore size distribution of the catalyst is a unimodal pore size distribution.

[0196] Propylene polymerization method was the same as described for Example 6, and the polymerization data of the catalyst and the polymer data are given in Table 3.

Comparative Example 6

[0197] A solid was prepared by the preparation method of Example 1 in patent CN1097597C, except that diisobutyl phthalate was changed to 1.5 g of 9,9-dimethoxymethylfluorene. Catalyst component data are given in Table 3.

[0198] The pore size data of the catalyst measured by nitrogen adsorption method are given in Table 2. The pore size distribution of the catalyst is a unimodal pore size distribution.

[0199] Propylene polymerization method was the same as described for Example 6, and the polymerization data of the catalyst and the polymer data are given in Table 3.

Comparative Example 7

[0200] A solid was prepared by the preparation method of Example 1 in patent CN1097597C, except that diisobutyl phthalate was changed to 1.5 ml of 2,4-pentanediol dibenzoate. Catalyst component data are given in Table 3.

[0201] The pore size data of the catalyst measured by nitrogen adsorption method are given in Table 2. The pore size distribution of the catalyst is a unimodal pore size distribution.

[0202] Propylene polymerization method was the same as described for Example 6, and the polymerization data of the catalyst and the polymer data are given in Table 3.

Comparative Example 8

[0203] A solid was prepared by the preparation method of Example 1 in patent CN1097597C, except that diisobutyl phthalate was changed to 1.5 ml of 2-isopropyl-2-isopentyl-1,3-dimethoxypropane. Catalyst component data are given in Table 3.

[0204] The pore size data of the catalyst measured by nitrogen adsorption method are given in Table 2. The pore size distribution of the catalyst is a unimodal pore size distribution.

[0205] Propylene polymerization method was the same as described for Example 6, and the polymerization data of the catalyst and the polymer data are given in Table 3.

TABLE-US-00002 TABLE 2 NLDFT algorithm The most The most probable probable pore size of pore size of Proportion Proportion Catalyst the peak in the peak in of the pore of the pore Specific pore size the pore size the pore size volume with volume with surface Pore distribution range of less range of at a pore a pore area volume Item profile than 10 nm, nm least 10 nm, nm size <5 nm size ≥30 nm (m.sup.2/g) (cm.sup.3/g) Example 6 multimodal 3.4 82.0 0.648 0.166 264.62 0.288 Example 7 multimodal 2.7 68.5 0.503 0.312 156.71 0.200 Example 8 multimodal 2.3 68.5 0.245 0.501 316.91 0.447 Example 9 multimodal 1.6 34.2 0.505 0.331 332.56 0.395 Example 10 multimodal 4.0 71.1 0.701 0.076 373.39 0.301 Example 11 multimodal 2.9 68.5 0.553 0.285 299.09 0.333 Example 12 multimodal 4.6 31.7 0.672 0.088 347.21 0.271 Example 13 multimodal 2.7 42.5 0.186 0.571 208.28 0.437 Comp. Ex. 3 unimodal 2.7 no peak 0.792 0.022 314.90 0.204 Comp. Ex. 4 unimodal 2.9 no peak 0.763 0.033 316.76 0.224 Comp. Ex. 5 unimodal 4.0 no peak 0.752 0.007 399.93 0.323 Comp. Ex. 6 unimodal 3.8 no peak 0.531 0.002 202.32 0.197 Comp. Ex. 7 unimodal 4.0 no peak 0.509 0.002 218.51 0.212 Comp. Ex. 8 unimodal 3.8 no peak 0.551 0.002 233.02 0.222 Notation: Under the NLDFT algorithm, the proportion of the pore volume with a pore size <5 nm refers to the ratio of the pore volume with a pore size <5 nm obtained by the NLDFT algorithm to the total pore volume calculated under this algorithm, and the other representations have analogical meanings. The pore volumes given in Table 2 are the BJH algorithm pore volume.

TABLE-US-00003 TABLE 3 Internal electron Polymerization Ti Mg donor activity BD II MI Item wt % wt % wt % KgPP/gCat g/cm.sup.3 wt % (g/10 min) MWD Example 6 1.78 18.3 8.4 38.4 0.43 98.3 4.3 6.1 Example 7 1.83 18.1 10.4 34.4 0.42 98.5 4.7 8.4 Example 8 1.83 18.1 9.4 54.7 0.44 98.5 3.7 5.2 Example 9 1.63 18.2 9.1 32.3 0.40 98.1 4.5 6.2 Example 10 3.62 17.5 9.3 28.8 0.39 98.4 3.3 5.7 Example 11* 1.94 17.7 9.2 58.2 0.43 98.0 3.5 5.8 Example 12 2.28 18.4 9.5 72.4 0.43 98.7 3.8 4.7 Example 13 1.78 18.7 9.5 56.1 0.42 98.5 3.8 4.9 Comp. Ex. 3 1.58 18.4 8.7 37.1 0.47 97.6 5.1 4.9 Comp. Ex. 4 1.82 18.3 8.7 32.5 0.45 97.8 3.6 5.3 Comp. Ex. 5 1.34 18.7 9.2 24.8 0.39 97.7 4.6 4.8 Comp. Ex. 6 2.13 18.6 9.9 54.1 0.45 98.1 3.8 3.7 Comp. Ex. 7 2.12 18.5 10.1 50.4 0.42 98.4 4.5 6.7 Comp. Ex. 8 2.10 18.3 9.4 42.1 0.45 97.5 3.6 3.2 *The content of internal electron donor for Example 11 is the content of 2-isopropyl-2-isopenty1-1,3-dimethoxypropane.

[0206] It can be seen from the data in Tables 1-3 and FIGS. 1-6 that the titanium-containing, magnesium-based solids and the magnesium chloride-supported olefin polymerization catalyst components obtained by the present invention have multimodal pore size distribution characteristics and higher specific surface areas, whereas the magnesium chloride-supported olefin polymerization catalysts shown in the comparative examples have unimodal pore size distribution characteristics. When the catalysts of the present invention are used for propylene polymerization, they have higher polymerization activities and higher stereo-orientation abilities, and the prepared polymers have wider molecular weight distribution.

[0207] It should be noted that the foregoing embodiments are only used to explain the present invention, and do not constitute any limitation to the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanative, rather than limitative. The present invention may be modified within the scope of the claims of the present invention as specified, and may be modified without departing from the scope and spirit of the present invention. Although the invention described herein refers to the specific methods, materials and embodiments, it is not intended to be limited to the specific examples disclosed therein, but rather, the invention extends to all other methods and applications having the same function.