A supported single-active-site catalyst, its preparation method, and its application.

Abstract

This application belongs to the field of olefin catalytic polymerization technology, specifically relating to a supported single-active-site catalyst, its preparation method, and its application. The single-active-site catalyst comprises a porous organic polymer support, a metallocene compound, and a co-catalyst; the supported single-active-site catalyst is a single-active-site catalyst supported on the porous organic polymer support; the porous organic polymer support is a homopolymer formed using functional monomers containing phenolic hydroxyl groups as polymerizing monomers. Based on the supported single-active-site catalyst provided in this application, when used to catalyze olefin polymerization, the resulting high-molecular-weight polyethylene exhibits higher viscosity-average molecular weight and lower PDI, while the catalyst also exhibits significantly higher catalytic activity.

Description

Technical Field

[0001] This application belongs to the field of olefin catalytic polymerization technology, specifically relating to a supported single-active-center catalyst, its preparation method, and its application. Background Technology

[0002] High molecular weight polyolefins (HMWPEs) typically refer to polyolefin materials with a weight-average molecular weight (Mw) of over 100,000, or even reaching several million (e.g., polyethylene, polypropylene). They occupy an irreplaceable position in strategic fields such as national defense, medical devices, high-performance fibers, and new energy, thanks to their superior performance and ever-expanding market applications. Catalysts are one of the key elements in the catalytic polymerization of ethylene to produce HMWPEs. Different catalyst choices directly determine polymerization kinetics, molecular weight, and molecular weight distribution, thus affecting the performance of the final material.

[0003] Currently, single-active-site catalysts are mainly used for producing high molecular weight polyolefins with narrow molecular weight distributions. Metallocene catalysts are the first generation of single-active-site catalysts, exhibiting excellent catalytic performance and producing highly homogeneous products with precise control over the molecular weight of polyolefin products. However, they also have some drawbacks: the morphology of the produced polymer is difficult to control, there is severe sticking to the reactor, and the use of large quantities of co-catalysts (such as methylaluminoxane, MAO) results in high costs. Therefore, supported catalysts are necessary.

[0004] Related technologies disclose the use of inorganic supports such as silica gel, magnesium chloride, molecular sieves, clay / nanomaterials, and others (such as Al2O3, activated carbon) to support metallocene catalysts. However, numerous studies have shown that inorganic supports typically require rigorous pretreatment to remove harmful surface groups and prevent deactivation of the catalyst's active sites. Furthermore, the catalytic activity of the supported catalyst decreases due to impaired mass transfer. Additionally, the use of inorganic supports increases the ash content of polyolefin products, leading to problems such as fisheye defects and fiber breakage in the film. Compared to inorganic supports, organic polymer supports exhibit certain advantages, including higher purity, lower ash content, superior optical properties, better copolymerization performance and molecular design capabilities, and environmental friendliness.

[0005] In recent years, porous organic polymer supports have shown great promise in the field of polyolefins due to their high activity, good copolymerization properties, and the ability to regulate polymer molecular weight through nano-confinement effects during olefin polymerization. For example, prior art CN115073628A discloses a metallocene catalyst system supported on a porous organic polymer support, its preparation method, and its application. Specifically, it discloses using divinylbenzene as the basic monomer and styrene containing benzenesulfonic acid functional groups or sulfonic acid groups as the functional monomer, preparing a porous organic polymer via dispersion polymerization to support a metallocene catalyst. The specific surface area of ​​the prepared support is 254~563 m². 2 The pore volume is 0.226~0.521mL / g, the homopolymerization activity of ethylene homopolymerization is 1980~3680g / gcat.h, and the bulk density is 0.31~0.36g / ml. However, the existing related technologies focus primarily on the activity of the catalyst for olefin polymerization and the bulk density of the polyethylene product, without paying much attention to the molecular weight and molecular weight distribution of the polyolefin obtained by the catalyst-catalyzed polymerization. Furthermore, the monomers used are complex and relatively more expensive.

[0006] Based on this, the present invention aims to develop a supported single-active-center catalyst for high molecular weight polyethylene that is efficient, stable, structurally tunable, low-cost, and capable of achieving a narrow molecular weight distribution under industrial reaction conditions. Summary of the Invention

[0007] The purpose of this application is to provide a supported single-active-site catalyst, its preparation method, and its application. The supported single-active-site catalyst provided in this application can achieve efficient, stable, and low-cost preparation of high molecular weight polyolefins with a narrow molecular weight distribution. The specific scheme is as follows: According to a first aspect of this application, this application provides a supported single-active-center catalyst, characterized in that the single-active-center catalyst is composed of a porous organic polymer support, a metallocene metal compound, and a co-catalyst; the supported single-active-center catalyst is a single-active-center catalyst supported on the porous organic polymer support; the porous organic polymer support is a homopolymer formed by polymerizing a functional monomer containing phenolic hydroxyl groups.

[0008] To address the shortcomings of existing porous organic polymer supports mentioned in the background section, the inventors of this application disclosed a porous organic polymer-supported metallocene catalyst and its preparation and application in their published patent document (CN121086108A). This catalyst is prepared by copolymerizing a functional monomer containing phenolic hydroxyl groups and a comonomer containing an aromatic ring via Friedel-Crafts alkylation. The porous organic polymer support obtained by olefin polymerization based on this porous organic polymer support exhibits a PDI range of 2.5–2.8, a catalytic activity range of 12814–20072 g-PE / mmol-Zr / h, and a viscosity-average molecular weight M of 4.6–6.4 × 10⁻⁶. 5 g / mol. Further research by the inventors of this application revealed that when only functional monomers containing phenolic hydroxyl groups are used as polymerizing monomers to obtain homopolymers as porous organic polymer supports, the average pore size of these supports can reach up to approximately 10 nm. Furthermore, catalysts obtained by loading metallocene compounds onto these porous organic polymer supports with larger average pore sizes, when used to catalyze olefin polymerization, produce polyethylene with higher viscosity-average molecular weight (an order of magnitude increase) and lower PDI. Simultaneously, catalysts obtained by loading metallocene compounds onto these porous organic polymer supports with larger average pore sizes exhibit significantly superior catalytic activity (up to 35337 g-PE / mmol-Hf / h).

[0009] In some embodiments of this application, the porous organic polymer support is obtained by Friedel-Crafts alkylation of a functional monomer containing phenolic hydroxyl groups under Lewis acid catalyst conditions.

[0010] In some embodiments of this application, the porous organic polymer support is obtained by dissolving the functional monomer containing phenolic hydroxyl groups in a chlorine-containing solvent, adding a Lewis acid catalyst and a crosslinking agent, and then performing a Friedel-Crafts alkylation reaction.

[0011] In some embodiments of this application, the chlorine-containing solvent includes one or more of dichloromethane, chloroform, carbon tetrachloride, and 1,2-dichloroethane.

[0012] In some embodiments of this application, the Lewis acid catalyst includes one or more of ferric chloride, aluminum chloride, zinc chloride, and boron trifluoride.

[0013] In some embodiments of this application, the crosslinking agent includes one or more of dimethoxymethane, chloromethyl methyl ether, and dibenzyl chloride.

[0014] In some embodiments of this application, the amount of crosslinking agent added relative to the amount of the functional monomer containing phenolic hydroxyl groups is 5-10 equivalents. Specifically, the amount of crosslinking agent added relative to the amount of the functional monomer containing phenolic hydroxyl groups can be 5 equivalents, 6 equivalents, 7 equivalents, 8 equivalents, 9 equivalents, 10 equivalents, or a range consisting of any two of the above values.

[0015] In some embodiments of this application, the amount of the Lewis acid catalyst added relative to the functional monomer containing the phenolic hydroxyl group is 10-40 equivalents. Specifically, the amount of the Lewis acid catalyst added relative to the functional monomer containing the phenolic hydroxyl group is 10 equivalents, 15 equivalents, 20 equivalents, 25 equivalents, 30 equivalents, 35 equivalents, 40 equivalents, or a range consisting of any two of the above values.

[0016] In some embodiments of this application, the functional monomer containing a phenolic hydroxyl group is selected from one or more of phenol, hydroquinone, catechol, phloroglucinol, p-bromophenol, m-bromophenol, p-benzyloxyphenol, eugenol, biphenol, p-hydroxyphenylethanol, 4-ethylphenol, and 3-fluorophenol.

[0017] In some embodiments of this application, the cocatalyst includes at least one of methylaluminoxane, modified methylaluminoxane, ethylaluminoxane, n-butylaluminoxane, or isopropylaluminoxane.

[0018] In some embodiments of this application, the metallocene compound has the general formula Cp. x MA y Bz; where Cp is an unsubstituted cyclopentadienyl, a substituted cyclopentadienyl, an indenyl, a fluorenyl, an indenyl ligand in hydrogenated form, or a fluorenyl ligand in hydrogenated form; M is a transition metal zirconium or hafnium; A and B are halogen atoms, hydrogen atoms, or alkyl groups, respectively; x is an integer from 1 to 3; and y and z are integers from 1 to 3.

[0019] In some embodiments of this application, the metallocene compound includes bis(cyclopentadienyl)zirconia dichloride, bis(cyclopentadienyl)hafnium dichloride, bis(cyclopentadienyl)titanium dichloride, bis(cyclopentadienyl)dimethylzirconia, bis(cyclopentadienyl)dimethylhafnium, bis(n-propylcyclopentadienyl)zirconia dichloride, bis(n-propylcyclopentadienyl)hafnium dichloride, bis(n-propylcyclopentadienyl)dimethylzirconia, bis(n-propylcyclopentadienyl)dimethylhafnium, bis(n-butylcyclopentadienyl)zirconia dichloride, bis(n-butylcyclopentadienyl)hafnium dichloride, bis(n-butylcyclopentadienyl)hafnium dichloride, bis(n-butylcyclopentadienyl)zil ... Dienyl)titanium dichloride, bis(n-butylcyclopentadienyl)dimethylzirconium, bis(n-butylcyclopentadienyl)dimethylhafnium, bis(dimethylcyclopentadienyl)dimethylzirconium, bis(tetramethylcyclopentadienyl)dimethylzirconium, diindylzirconium dichloride, diindylhafnium dichloride, bis(1-methyl-3-n-butylcyclopentadienyl)zirconium dichloride, bis(1-methyl-3-n-butylcyclopentadienyl)hafnium dichloride, isopropyl(cyclopentadienyl)(fluorenyl)zirconium dichloride, methylene-bridged diindylzirconium dichloride and bis(4,5,6,7-tetrahydro-1-indyl)zirconium dichloride, methylene-bridged diindyl ... Ethyl-bridged di(indenyl)zirconia, methylene-bridged diindenyl hafnium chloride and bis(4,5,6,7-tetrahydro-1-indenyl)hafnium chloride, ethyl-bridged di(indenyl)hafnium chloride, ethyl-bridged di(indenyl)titanium chloride, bis(4,5,6,7-tetrahydro-1-indenyl)titanium chloride, diphenylmethylene(cyclopentadienyl)(fluorenyl)zirconia, diphenylmethylene(cyclopentadienyl)(fluorenyl)hafnium chloride, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)zirconia, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)zirconia At least one of the following: hafnium dichloride, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)dimethylzirconium, dimethylsilyl-bridged bis(2-methylindenyl)zirconium dichloride, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)dimethylzirconium dichloride, dimethylsilyl-bridged bis(2-methyl-benzoindenyl)dimethylzirconium dichloride, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)dimethylzirconium dichloride, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)dimethylzirconium dichloride.

[0020] In some embodiments of this application, the metallocene compound has the general formula Cp. x MA y Bz; where Cp is n-propylcyclopentadienyl or n-butylcyclopentadienyl, M is the transition metal zirconium or hafnium, A and B are halogen atoms, hydrogen atoms or alkyl groups respectively, x is an integer from 1 to 3, and y and z are integers from 1 to 3.

[0021] In some embodiments of this application, the metallocene compound includes at least one of bis(n-propylcyclopentadienyl)zirconium dichloride, bis(n-propylcyclopentadienyl)hafnium dichloride, bis(n-propylcyclopentadienyl)dimethylzirconium, and bis(n-propylcyclopentadienyl)dimethylhafnium.

[0022] In some embodiments of this application, the mass ratio of the co-catalyst to the support is 1-5:5-10, and the mass ratio of the metallocene compound to the support is 0.5-2:40-60. Specifically, the mass ratio of the co-catalyst to the support can be 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, 2:5, 2:6, 2:7, 2:8, 2:9, 2:10, 3:5, 3:6, 3:7, 3:8, 3:9, 3:10, 4:5, 4:6, 4:7, 4:8, 4:9, 4:10, 5:5, 5:6, 5:7, 5:8, 5:9, 5:10, or a range consisting of any two of the above values. Preferably, the mass ratio of the co-catalyst to the support is 4:5.

[0023] In some embodiments of this application, the mass ratio of the metallocene compound to the support is 0.5~2:40~60. Specifically, the mass ratio of the metallocene compound to the support can be 0.5:40, 0.5:45, 0.5:50, 0.5:55, 0.5:60, 1:40, 1:45, 1:50, 1:55, 1:60, 1.5:40, 1.5:45, 1.5:50, 1.5:55, 1.5:60, 2:40, 2:45, 2:50, 2:55, 2:60, or a range consisting of any two of the above values. Preferably, the mass ratio of the metallocene compound to the support is 1:50.

[0024] According to a second aspect of this application, this application also provides a method for preparing a supported single-active-site catalyst, the preparation method comprising: 1. A porous organic polymer support is prepared by dissolving a functional monomer containing phenolic hydroxyl groups in a chlorine-containing solvent, adding a Lewis acid catalyst and a crosslinking agent, and carrying out a Friedel-Crafts alkylation reaction. 2. The porous organic polymer support is reacted with a co-catalyst in a first organic medium to activate it, thereby obtaining the activated porous organic polymer support. 3. The metallocene compound is dissolved in a second organic medium and reacted with the porous organic polymer support to obtain the supported single-active-center catalyst; the supported single-active-center catalyst is a single-active-center catalyst supported on a porous organic polymer support.

[0025] In some embodiments of this application, the chlorine-containing solvent includes one or more of dichloromethane, chloroform, carbon tetrachloride, and 1,2-dichloroethane; preferably, the Lewis acid catalyst includes one or more of ferric chloride, aluminum trichloride, zinc chloride, and boron trifluoride.

[0026] In some embodiments of this application, the crosslinking agent includes one or more of dimethoxymethane, chloromethyl methyl ether, and dibenzyl chloride.

[0027] In some embodiments of this application, the amount of crosslinking agent added relative to the amount of the functional monomer containing phenolic hydroxyl groups is 5-10 equivalents. Specifically, the amount of crosslinking agent added relative to the amount of the functional monomer containing phenolic hydroxyl groups can be 5 equivalents, 6 equivalents, 7 equivalents, 8 equivalents, 9 equivalents, 10 equivalents, or a range consisting of any two of the above values.

[0028] In some embodiments of this application, the amount of the Lewis acid catalyst added relative to the functional monomer containing the phenolic hydroxyl group is 10-40 equivalents. Specifically, the amount of the Lewis acid catalyst added relative to the functional monomer containing the phenolic hydroxyl group is 10 equivalents, 15 equivalents, 20 equivalents, 25 equivalents, 30 equivalents, 35 equivalents, 40 equivalents, or a range consisting of any two of the above values.

[0029] In some embodiments of this application, the functional monomer containing a phenolic hydroxyl group is selected from one or more of phenol, hydroquinone, catechol, phloroglucinol, p-bromophenol, m-bromophenol, p-benzyloxyphenol, eugenol, biphenol, p-hydroxyphenylethanol, 4-ethylphenol, and 3-fluorophenol.

[0030] In some embodiments of this application, the Friedel-Crafts alkylation reaction is carried out under the following conditions: 50-100°C and a protective atmosphere for 1-15 hours. Specifically, the temperature of the Friedel-Crafts alkylation reaction can be 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, or any combination of two of the above values. Specifically, the time of the Friedel-Crafts alkylation reaction can be 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, or any combination of two of the above values.

[0031] In some embodiments of this application, the cocatalyst includes at least one of methylaluminoxane, modified methylaluminoxane, ethylaluminoxane, n-butylaluminoxane, or isopropylaluminoxane.

[0032] In some embodiments of this application, the first organic medium and the second organic medium are each independently selected from at least one of tetrahydrofuran, diethyl ether, toluene, benzene, chloroform, dichloromethane, petroleum ether, n-hexane, and n-heptane.

[0033] In some embodiments of this application, the metallocene compound has the general formula Cp. x MA y Bz; where Cp is an unsubstituted cyclopentadienyl, a substituted cyclopentadienyl, an indenyl, a fluorenyl, an indenyl ligand in hydrogenated form, or a fluorenyl ligand in hydrogenated form; M is a transition metal zirconium or hafnium; A and B are halogen atoms, hydrogen atoms, or alkyl groups, respectively; x is an integer from 1 to 3; and y and z are integers from 1 to 3.

[0034] In some embodiments of this application, the metallocene compound includes bis(cyclopentadienyl)zirconia dichloride, bis(cyclopentadienyl)hafnium dichloride, bis(cyclopentadienyl)titanium dichloride, bis(cyclopentadienyl)dimethylzirconia, bis(cyclopentadienyl)dimethylhafnium, bis(n-propylcyclopentadienyl)zirconia dichloride, bis(n-propylcyclopentadienyl)hafnium dichloride, bis(n-propylcyclopentadienyl)dimethylzirconia, bis(n-propylcyclopentadienyl)dimethylhafnium, bis(n-butylcyclopentadienyl)zirconia dichloride, bis(n-butylcyclopentadienyl)hafnium dichloride, bis(n-butylcyclopentadienyl)hafnium dichloride, bis(n-butylcyclopentadienyl)zil ... Dienyl)titanium dichloride, bis(n-butylcyclopentadienyl)dimethylzirconium, bis(n-butylcyclopentadienyl)dimethylhafnium, bis(dimethylcyclopentadienyl)dimethylzirconium, bis(tetramethylcyclopentadienyl)dimethylzirconium, diindylzirconium dichloride, diindylhafnium dichloride, bis(1-methyl-3-n-butylcyclopentadienyl)zirconium dichloride, bis(1-methyl-3-n-butylcyclopentadienyl)hafnium dichloride, isopropyl(cyclopentadienyl)(fluorenyl)zirconium dichloride, methylene-bridged diindylzirconium dichloride and bis(4,5,6,7-tetrahydro-1-indyl)zirconium dichloride, methylene-bridged diindyl ... Ethyl-bridged di(indenyl)zirconia, methylene-bridged diindenyl hafnium chloride and bis(4,5,6,7-tetrahydro-1-indenyl)hafnium chloride, ethyl-bridged di(indenyl)hafnium chloride, ethyl-bridged di(indenyl)titanium chloride, bis(4,5,6,7-tetrahydro-1-indenyl)titanium chloride, diphenylmethylene(cyclopentadienyl)(fluorenyl)zirconia, diphenylmethylene(cyclopentadienyl)(fluorenyl)hafnium chloride, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)zirconia, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)zirconia At least one of the following: hafnium dichloride, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)dimethylzirconium, dimethylsilyl-bridged bis(2-methylindenyl)zirconium dichloride, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)dimethylzirconium dichloride, dimethylsilyl-bridged bis(2-methyl-benzoindenyl)dimethylzirconium dichloride, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)dimethylzirconium dichloride, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)dimethylzirconium dichloride.

[0035] In some embodiments of this application, the metallocene compound has the general formula Cp. x MA y Bz; where Cp is n-propylcyclopentadienyl or n-butylcyclopentadienyl, M is the transition metal zirconium or hafnium, A and B are halogen atoms, hydrogen atoms or alkyl groups respectively, x is an integer from 1 to 3, and y and z are integers from 1 to 3.

[0036] In some embodiments of this application, the metallocene compound includes at least one of bis(n-propylcyclopentadienyl)zirconium dichloride, bis(n-propylcyclopentadienyl)hafnium dichloride, bis(n-propylcyclopentadienyl)dimethylzirconium, and bis(n-propylcyclopentadienyl)dimethylhafnium.

[0037] In some embodiments of this application, the mass ratio of the co-catalyst to the support is 1~5:5~10. Specifically, the mass ratio of the co-catalyst to the support can be 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, 2:5, 2:6, 2:7, 2:8, 2:9, 2:10, 3:5, 3:6, 3:7, 3:8, 3:9, 3:10, 4:5, 4:6, 4:7, 4:8, 4:9, 4:10, 5:5, 5:6, 5:7, 5:8, 5:9, 5:10, or a range consisting of any two of the above values. Preferably, the mass ratio of the co-catalyst to the support is 4:5.

[0038] In some embodiments of this application, the mass ratio of the metallocene compound to the support is 0.5~2:40~60. Specifically, the mass ratio of the metallocene compound to the support can be 0.5:40, 0.5:45, 0.5:50, 0.5:55, 0.5:60, 1:40, 1:45, 1:50, 1:55, 1:60, 1.5:40, 1.5:45, 1.5:50, 1.5:55, 1.5:60, 2:40, 2:45, 2:50, 2:55, 2:60, or a range consisting of any two of the above values. Preferably, the mass ratio of the metallocene compound to the support is 1:50.

[0039] According to a third aspect of this application, this application also provides the application of a supported single-active-center catalyst as described in any one of the first aspects of this application and / or a supported single-active-center catalyst prepared by any one of the preparation methods described in any one of the second aspects of this application in olefin polymerization.

[0040] In some embodiments of this application, the olefin polymerization includes ethylene homopolymerization, propylene homopolymerization, copolymerization of ethylene and propylene, copolymerization of ethylene and α-olefins, or copolymerization of propylene and α-olefins. In some embodiments of this application, the α-olefin is butene, pentene, hexene, octene, or 4-methyl-1-pentene. Using the supported single-active-center catalyst to catalyze olefin polymerization yields polyolefins with higher viscosity-average molecular weight and lower PDI molecular weight distribution; that is, high molecular weight polyolefins with a narrow molecular weight distribution can be prepared, especially high molecular weight polyethylene with a narrow molecular weight distribution.

[0041] According to a fourth aspect of this application, this application also provides a method for preparing a high molecular weight polyolefin, the method comprising: using a supported single-active-center catalyst as described in any one of the first aspects of this application and / or a supported single-active-center catalyst prepared by the preparation method as described in any one of the second aspects of this application as a catalyst to carry out a polymerization reaction to obtain the high molecular weight polyolefin.

[0042] In some embodiments of this application, the preparation method includes: using a supported single-active-center catalyst as described in any one of the first aspects of this application and / or a supported single-active-center catalyst prepared by the preparation method as described in any one of the second aspects of this application as the main catalyst, and an alkyl aluminum compound as the co-catalyst, to carry out a polymerization reaction of olefin monomers in an organic medium, and the resulting product is filtered and dried to obtain the high molecular weight polyolefin.

[0043] In some embodiments of this application, the polymerization reaction includes any one of slurry polymerization, gas-phase polymerization, or solution polymerization. In some embodiments of this application, the olefin polymerization monomer includes at least one of ethylene, propylene, butene, pentene, hexene, octene, or 4-methyl-1-pentene.

[0044] In some embodiments of this application, the alkylaluminum compound includes at least one of trimethylaluminum, triethylaluminum, tri-n-propylaluminum, triisobutylaluminum, tri-n-butylaluminum, methylaluminoxane, modified methylaluminoxane, ethylaluminoxane, n-butylaluminoxane, or isopropylaluminoxane.

[0045] In some embodiments of this application, the organic medium is selected from at least one of tetrahydrofuran, diethyl ether, toluene, benzene, chloroform, dichloromethane, petroleum ether, n-hexane, and n-heptane.

[0046] In some embodiments of this application, the polymerization reaction temperature is 0~100℃ and the time is 1~12h. Specifically, the polymerization reaction temperature can be 0℃, 5℃, 10℃, 15℃, 20℃, 25℃, 30℃, 35℃, 40℃, 45℃, 50℃, 55℃, 60℃, 65℃, 70℃, 75℃, 80℃, 85℃, 90℃, 95℃, 100℃, or a range of any two of the above values. Specifically, the polymerization reaction time can be 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, or a range of any two of the above values.

[0047] In summary, the present invention has at least one of the following beneficial technical effects: This application provides a supported single-active-site catalyst. The catalyst uses a copolymer formed by copolymerizing functional monomers containing phenolic hydroxyl groups as polymeric monomers as the supporting support. On one hand, the pore size of this porous organic polymer support is adjustable, with a maximum average pore size >10 nm. Furthermore, the supported single-active-site catalyst formed based on this support exhibits stable and efficient catalytic performance, maintaining high activity (>30000 kg PE·(molmetal)) under industrially feasible conditions (75°C, 10 bar ethylene pressure). -1 ·h -1 On the other hand, the high molecular weight polyolefins obtained by polymerization using this catalyst have higher viscosity-average molecular weights, with the highest exceeding 2.0 × 10⁻⁶. 6 g / mol, while the resulting high molecular weight polyolefin has low ash content and narrow molecular weight distribution, exhibiting excellent processing and application performance. Attached Figure Description

[0048] Figure 1 The gas adsorption-desorption curve (BET plot) of the porous organic polymer support prepared in one embodiment of this application; Figure 2 EDM approximation of catalyst 1 supported on a porous organic polymer support, prepared according to an embodiment of this application; Figure 3 This is the GPC data for high molecular weight polyethylene obtained by catalytic polymerization in one embodiment of this application. Detailed Implementation

[0049] The technical solutions of this application are further illustrated below through specific embodiments. These specific embodiments do not represent a limitation on the scope of protection of this application. Any non-essential modifications and adjustments made by others based on the concept of this application still fall within the scope of protection of this application.

[0050] The test methods used in the following examples and comparative examples are as follows: (1) Specific surface area, pore volume and average pore size of the carrier: The specific surface area and porosity were determined by nitrogen (N2) adsorption-desorption at 77 K using a Micromeritics 3Flex fully automatic specific surface area and porosity analyzer. (2) Catalytic activity of catalyst for ethylene polymerization: can be calculated by formula: A=mPE / mCat (Formula 1), where mPE is the mass of polyethylene (g) and mCat is the amount of catalyst added (g), and the activity unit is expressed as g PE / g Cat; or it can be calculated by formula: A=mPE / (n*t) (Formula 2), where mPE is the mass of polyethylene (g), n is the amount of transition metal in the catalyst (mmol), t is the reaction time, and the activity unit is expressed as mPg-PE / mmol-metal / h or K mPg-PE / mol-metal / h. The content of transition metal in the catalyst is determined in advance by inductively coupled plasma optical emission spectroscopy (ICP-OES).

[0051] (3) Viscosity-average molecular weight of polyethylene: The intrinsic viscosity [η] is measured by using an Ubbelohde viscometer, and then calculated according to the formula The viscosity-average molecular weight of polyethylene was calculated.

[0052] (4) Molecular weight distribution of polyethylene (PDI): The molecular weight distribution of polyethylene (PDI) was determined by high temperature gel permeation chromatography (GPC, Agilent PL-GPC220, USA).

[0053] Part 1: Preparation of Porous Organic Polymer Supports Example 1-1 This embodiment provides a method for preparing a porous organic polymer support, the specific preparation method of which is as follows: Phenol (5 mmol) was dissolved in 50 mL of 1,2-dichloroethane under argon atmosphere and stirred at room temperature for 10 minutes. Seven equivalents of crosslinking agent dimethoxymethane were added, and the mixture was stirred at room temperature until completely dissolved. Twenty equivalents of Lewis acid catalyst (FeCl3) were added, and the reaction was carried out under sealed conditions at 80 °C for 6 hours. After the reaction was complete, the mixture was cooled to room temperature, filtered, washed, and vacuum dried for at least 6 hours. The solid was then ground into a fine powder to obtain support 1, which has a specific surface area of ​​23 m². 2 / g, pore volume 0.04 cm³ 3 / g, with an average pore size of 7.68 nm.

[0054] Meanwhile, the gas adsorption-desorption curve of the carrier prepared in this embodiment is shown in the figure. Figure 1 As shown in the figure. In this example, the pore structure of the prepared porous organic polymer support was studied by nitrogen (N2) adsorption curve. The N2 adsorption-desorption isotherm shows that the N2 absorption increases rapidly in the low relative pressure region, which may be due to micropore filling, indicating that there is a certain amount of micropores. As the relative pressure increases, the adsorbate undergoes capillary condensation, exhibiting the behavior of a mesoporous material. Therefore, it can be inferred that the support contains a multi-level pore structure.

[0055] Example 2-1 This embodiment provides a method for preparing a porous organic polymer support, the specific preparation method of which is as follows: Phenol (5 mmol) was dissolved in 50 mL of 1,2-dichloroethane under argon atmosphere and stirred at room temperature for 10 minutes. Five equivalents of crosslinking agent dimethoxymethane were added, and the mixture was stirred at room temperature until completely dissolved. 40 equivalents of Lewis acid catalyst (FeCl3) were added, and the reaction was carried out under sealed conditions at 80 °C for 6 hours. After the reaction was complete, the mixture was cooled to room temperature, filtered, washed, and vacuum dried for at least 6 hours. The solid was then ground into a fine powder to obtain support 2. The specific surface area of ​​support 2 was 21 m². 2 / g, pore volume 0.03 cm³ 3 / g, with an average pore size of 10.52 nm.

[0056] Comparative Example 1-1 This comparative example provides a method for preparing a porous organic polymer support, the specific preparation method of which is as follows: Phenol and benzene were dissolved in 50 mL of 1,2-dichloroethane at a molar ratio of 1:3 under argon atmosphere. The mixture was stirred at room temperature for 10 minutes, and then 40 equivalents of crosslinking agent dimethoxymethane were added. The mixture was stirred at room temperature until completely dissolved. Then, 40 equivalents of Lewis acid catalyst (FeCl3) were added, and the reaction was carried out under sealed conditions at 80 °C for 6 hours. After the reaction was complete, the mixture was cooled to room temperature, filtered, washed, and vacuum dried for at least 6 hours. The solid was then ground into a fine powder to obtain support 3. The specific surface area of ​​support 3 is 837 m². 2 / g, pore volume 0.46cm 3 / g, with an average pore size of 3.47 nm.

[0057] The parameters of the porous organic polymer supports prepared according to the examples and comparative examples in Part 1 are shown in Table 1: Table 1

[0058] Part Two: Catalyst Preparation Example 2-1 This embodiment, based on the porous organic polymer support prepared in the first part, further provides a method for preparing a catalyst based on the porous organic polymer support, the specific steps of which are as follows: Weigh 500 mg of the support 1 (phenol) prepared in Example 1-1 into a Schlenk tube in a glove box, add toluene (10 mL) and methylaluminoxane (MAO) (400 mg) in sequence, and stir gently at 110 °C for 3 hours; after filtration, wash with toluene 2-3 times, dry under vacuum and transfer to a glove box to obtain the activated support; transfer the activated support to a container, add 10 mL of a toluene solution of 10 mg of di(n-propylcyclopentadienyl)hafnium dichloride dropwise to the container, and stir gently at room temperature for 2 hours; after filtration, wash with toluene 2-3 times, dry under vacuum and obtain catalyst 1.

[0059] The EDS mapping diagram of the catalyst prepared by this example is shown below. Figure 2 As shown. According to Figure 2 The results show that the elements Al, Hf, O and C in the catalyst are uniformly dispersed throughout the catalyst matrix, indicating that MAO and metallocene catalysts have been successfully loaded step by step and no metal agglomeration has occurred.

[0060] Example 2-2 This embodiment provides a method for preparing a catalyst based on a porous organic polymer support, based on Example 2-1. The only difference between this embodiment and Example 2-1 is that the support used is support 2 prepared in Example 1-2; all other aspects are the same. Catalyst 2 is prepared.

[0061] Example 2-3 This embodiment provides a method for preparing a catalyst based on a porous organic polymer support, based on Example 2-1. The only difference between this embodiment and Example 2-1 is that the support used is support 2 prepared in Example 1-2, and the activator is trimethylaluminum; all other aspects are the same. Catalyst 3 is prepared.

[0062] Examples 2-4 This embodiment is based on Example 2-1, which provides a method for preparing a catalyst based on a porous organic polymer support. The only difference between this embodiment and Example 2-1 is that the catalyst used is di(n-propylcyclopentadienyl)dimethylhafnium; all other aspects are the same. Catalyst 4 was prepared.

[0063] Comparative Example 2-1 This embodiment is based on Example 2-1, which provides a method for preparing a catalyst based on a porous organic polymer support. The only difference between this embodiment and Example 2-1 is that the catalyst used is di(n-propylcyclopentadienyl)zirconium dichloride; all other aspects are the same. Catalyst 5 was prepared.

[0064] Comparative Example 2-2 This comparative example is based on Example 2-1, which provides a method for preparing a catalyst based on a porous organic polymer support. The only difference between this comparative example and Example 2-1 is that the support used is the support 3 prepared in Comparative Example 1-1; all other aspects are the same. Catalyst 6 was prepared.

[0065] Comparative Examples 2-3 This comparative example is based on Example 2-1, which provides a method for preparing a catalyst based on a porous organic polymer support. The only difference between this comparative example and Example 2-1 is that the catalyst used is bis(n-butylcyclopentadienyl)hafnium dichloride; all other aspects are the same. Catalyst 7 was prepared.

[0066] Comparative Examples 2-4 This comparative example is based on Example 2-1, which provides a method for preparing a catalyst based on a porous organic polymer support. The only difference between this comparative example and Example 2-1 is that the catalyst used is di(cyclopentadienyl)zirconium dichloride; all other aspects are the same. Catalyst 8 was prepared.

[0067] Comparative Examples 2-5 This comparative example is based on Example 2-1, which provides a method for preparing a catalyst based on a porous organic polymer support. The only difference between this comparative example and Example 2-1 is that the catalyst used is diindenezirconium dichloride; all other aspects are the same. Catalyst 9 was prepared.

[0068] Comparative Examples 2-6 This comparative example is based on Example 2-1, which provides a method for preparing a catalyst based on a porous organic polymer support. The only difference between this comparative example and Example 2-1 is that the support used is the support 3 prepared in Comparative Example 1-1, and the catalyst used is bis(n-butylcyclopentadienyl)hafnium dichloride; all other aspects are the same. Catalyst 10 was prepared.

[0069] The parameters of the catalysts prepared based on porous organic polymer supports according to the examples and comparative examples in Part II are shown in Table 2: Table 2

[0070] Part Three: Application of Catalysts - Catalytic Olefin Polymerization Example 3-1 This embodiment, based on the catalyst prepared in the second part using a porous organic polymer support, further provides a method for using the catalyst based on a porous organic polymer support to catalyze olefin polymerization. The specific steps are as follows: Under nitrogen protection, 1000 mL of n-hexane and 0.5 g of triisobutylaluminum were added to a stainless steel polymerization reactor. The reactor temperature was adjusted to 75 °C and kept stable. 50.0 mg of catalyst 1 prepared in Example 2-1 was weighed, suspended in n-heptane, and added to the reactor. The ethylene pressure was quickly adjusted to 1.0 MPa and the timer was started, maintaining a constant ethylene pressure throughout the polymerization process. After 2 h of reaction, the ethylene gas supply was stopped, and the ethylene gas in the polymerization reactor was slowly released. The mixture was filtered to obtain white solid polyethylene. The polyethylene was then vacuum dried until constant weight was achieved.

[0071] The GPC data of the polyethylene resin prepared by this example are as follows: Figure 3 As shown. According to Figure 3 The results show that the polyethylene resin has a high molecular weight and a narrow molecular weight distribution.

[0072] Example 3-2 This embodiment is based on Example 3-1 and further provides a method for catalyzing olefin polymerization using a catalyst based on a porous organic polymer support. The only difference between this embodiment and Example 3-1 is that the catalyst used is catalyst 2 prepared in Example 2-2.

[0073] Example 3-3 This embodiment is based on Example 3-1 and further provides a method for catalyzing olefin polymerization using a catalyst based on a porous organic polymer support. The only difference between this embodiment and Example 3-1 is that the catalyst used is catalyst 3 prepared in Example 2-3.

[0074] Examples 3-4 This embodiment is based on Example 3-1 and further provides a method for catalyzing olefin polymerization using a catalyst based on a porous organic polymer support. The only difference between this embodiment and Example 3-1 is that the catalyst used is catalyst 4 prepared in Example 2-4.

[0075] Comparative Example 3-1 This embodiment is based on Example 3-1 and further provides a method for catalyzing olefin polymerization using a catalyst based on a porous organic polymer support. The only difference between this embodiment and Example 3-1 is that the catalyst used is catalyst 5 obtained in Comparative Example 2-1.

[0076] Comparative Example 3-2 This comparative example is based on Example 3-1 and further provides a method for catalyzing olefin polymerization using a catalyst based on a porous organic polymer support. The only difference between this comparative example and Example 3-1 is that the catalyst used is catalyst 6 prepared in Comparative Example 2-2.

[0077] Comparative Example 3-3 This comparative example is based on Example 3-1 and further provides a method for catalyzing olefin polymerization using a catalyst based on a porous organic polymer support. The only difference between this comparative example and Example 3-1 is that the catalyst used is catalyst 7 prepared in Comparative Example 2-3.

[0078] Comparative Examples 3-4 This comparative example is based on Example 3-1 and further provides a method for catalyzing olefin polymerization using a catalyst based on a porous organic polymer support. The only difference between this comparative example and Example 3-1 is that the catalyst used is catalyst 8 prepared in Comparative Examples 2-4.

[0079] Comparative Examples 3-5 This comparative example is based on Example 3-1 and further provides a method for catalyzing olefin polymerization using a catalyst based on a porous organic polymer support. The only difference between this comparative example and Example 3-1 is that the catalyst used is catalyst 9 prepared in Comparative Example 2-5.

[0080] Comparative Examples 3-6 This comparative example is based on Example 3-1 and further provides a method for catalyzing olefin polymerization using a catalyst based on a porous organic polymer support. The only difference between this comparative example and Example 3-1 is that the catalyst used is catalyst 10 prepared in Comparative Examples 2-6.

[0081] The results obtained from the olefin polymerization of the examples and comparative examples in Part III above are shown in Table 3: Table 3

[0082] It is understood that this application has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the scope of this application. Furthermore, based on the teachings of this application, these features and embodiments can be modified to adapt to specific situations and materials without departing from the scope of this application. Therefore, this application is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are protected by this application.

Claims

1. A supported single-active-site catalyst, characterized in that, The single-active-center catalyst is composed of a porous organic polymer support, a metallocene compound, and a co-catalyst; the supported single-active-center catalyst is a single-active-center catalyst supported on the porous organic polymer support; the porous organic polymer support is a homopolymer formed by polymerizing functional monomers containing phenolic hydroxyl groups.

2. The supported single-active-site catalyst according to claim 1, characterized in that, The porous organic polymer support is obtained by carrying out Friedel-Crafts alkylation of functional monomers containing phenolic hydroxyl groups under Lewis acid catalyst conditions. Preferably, the functional monomer containing a phenolic hydroxyl group is selected from one or more of phenol, hydroquinone, catechol, phloroglucinol, p-bromophenol, m-bromophenol, p-benzyloxyphenol, eugenol, biphenol, p-hydroxyphenylethanol, 4-ethylphenol, and 3-fluorophenol.

3. The supported single-active-center catalyst according to claim 1, characterized in that, The cocatalyst includes at least one of methylaluminoxane, modified methylaluminoxane, ethylaluminoxane, n-butylaluminoxane, or isopropylaluminoxane.

4. The supported single-active-center catalyst according to claim 1, characterized in that, The metallocene compound has the general formula Cp x MA y Bz; where Cp is an unsubstituted cyclopentadienyl, a substituted cyclopentadienyl, an indenyl, a fluorenyl, an indenyl ligand in hydrogenated form, or a fluorenyl ligand in hydrogenated form; M is a transition metal zirconium or hafnium; A and B are halogen atoms, hydrogen atoms, or alkyl groups, respectively; x is an integer from 1 to 3; and y and z are integers from 1 to 3. Preferably, the metallocene compound comprises bis(cyclopentadienyl)zirconia dichloride, bis(cyclopentadienyl)hafnium dichloride, bis(cyclopentadienyl)titanium dichloride, bis(cyclopentadienyl)dimethylzirconia, bis(cyclopentadienyl)dimethylhafnium, bis(n-propylcyclopentadienyl)zirconia dichloride, bis(n-propylcyclopentadienyl)hafnium dichloride, bis(n-propylcyclopentadienyl)dimethylzirconia, bis(n-propylcyclopentadienyl)dimethylhafnium, bis(n-butylcyclopentadienyl)zirconia dichloride, bis(n-butylcyclopentadienyl)hafnium dichloride, bis(n-butylcyclopentadienyl)di ... Titanium chloride, bis(n-butylcyclopentadienyl)dimethylzirconium, bis(n-butylcyclopentadienyl)dimethylhafnium, bis(dimethylcyclopentadienyl)dimethylzirconium, bis(tetramethylcyclopentadienyl)dimethylzirconium, diindylzirconium dichloride, diindylhafnium dichloride, bis(1-methyl-3-n-butylcyclopentadienyl)zirconium dichloride, bis(1-methyl-3-n-butylcyclopentadienyl)hafnium dichloride, isopropyl(cyclopentadienyl)(fluorenyl)zirconium dichloride, methylene-bridged diindylzirconium dichloride and bis(4,5,6,7-tetrahydro-1-indyl)zirconium dichloride, ethylene-bridged... Di(indenyl)zirconia, methylene-bridged diindenyl hafnium chloride and di(4,5,6,7-tetrahydro-1-indenyl)hafnium chloride, ethylene-bridged di(indenyl)hafnium chloride, ethylene-bridged di(indenyl)titanium chloride, di(4,5,6,7-tetrahydro-1-indenyl)titanium chloride, diphenylmethylene(cyclopentadienyl)(fluorenyl)zirconia, diphenylmethylene(cyclopentadienyl)(fluorenyl)hafnium chloride, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)zirconia, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)zirconia At least one of the following: hafnium chloride, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)dimethylzirconium, dimethylsilyl-bridged bis(2-methylindenyl)zirconium dichloride, dimethylsilyl-bridged bis(2-methyl-indenyl)hafnium dichloride, dimethylsilyl-bridged bis(2-methyl-benzo[a]indenyl)zirconium dichloride, dimethylsilyl-bridged bis(2-methyl-benzo[a]indenyl)hafnium dichloride, dimethylsilyl-bridged bis(2-methyl-benzo[a]indenyl)dimethylzirconium, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)dimethylzirconium; Preferably, the metallocene compound has the general formula Cp. x MA y Bz; where Cp is n-propylcyclopentadienyl or n-butylcyclopentadienyl, M is the transition metal zirconium or hafnium, A and B are halogen atoms, hydrogen atoms or alkyl groups respectively, x is an integer from 1 to 3, and y and z are integers from 1 to 3; Preferably, the metallocene compound includes at least one of bis(n-propylcyclopentadienyl)zirconium dichloride, bis(n-propylcyclopentadienyl)hafnium dichloride, bis(n-propylcyclopentadienyl)dimethylzirconium, and bis(n-propylcyclopentadienyl)dimethylhafnium.

5. The supported single-active-center catalyst according to claim 1, characterized in that, The mass ratio of the co-catalyst to the support is 1~5:5~10; the mass ratio of the metallocene compound to the support is 0.5~2:40~60.

6. A method for preparing a supported single-active-site catalyst, characterized in that, The preparation method includes:

1. A porous organic polymer support is prepared by dissolving a functional monomer containing phenolic hydroxyl groups in a chlorine-containing solvent, adding a Lewis acid catalyst and a crosslinking agent, and carrying out a Friedel-Crafts alkylation reaction.

2. The porous organic polymer support is reacted with a co-catalyst in a first organic medium to activate it, thereby obtaining the activated porous organic polymer support.

3. The metallocene compound is dissolved in a second organic medium and reacted with the porous organic polymer support to obtain the supported single-active-center catalyst; the supported single-active-center catalyst is a single-active-center catalyst supported on a porous organic polymer support.

7. The preparation method according to claim 6, characterized in that, The chlorinated solvent includes one or more of dichloromethane, chloroform, carbon tetrachloride, and 1,2-dichloroethane; preferably, the Lewis acid catalyst includes one or more of ferric chloride, aluminum trichloride, zinc chloride, and boron trifluoride; preferably, the crosslinking agent includes one or more of dimethoxymethane, chloromethyl methyl ether, and dibenzyl chloride; the amount of the crosslinking agent added relative to the amount of the functional monomer containing phenolic hydroxyl groups is 5-10 equivalents; preferably, the amount of the Lewis acid catalyst added relative to the amount of the functional monomer containing phenolic hydroxyl groups is 10-40 equivalents. Preferably, the functional monomer containing a phenolic hydroxyl group is selected from one or more of phenol, hydroquinone, catechol, phloroglucinol, p-bromophenol, m-bromophenol, p-benzyloxyphenol, eugenol, biphenol, p-hydroxyphenylethanol, 4-ethylphenol, and 3-fluorophenol; Preferably, the Friedel-Crafts alkylation reaction is carried out at 50-100°C under a protective atmosphere for 1-15 hours.

8. The preparation method according to claim 6, characterized in that, The cocatalyst includes at least one of methylaluminoxane, modified methylaluminoxane, ethylaluminoxane, n-butylaluminoxane, or isopropylaluminoxane. Preferably, the first organic medium and the second organic medium are each independently selected from at least one of tetrahydrofuran, diethyl ether, toluene, benzene, chloroform, dichloromethane, petroleum ether, n-hexane, and n-heptane; Preferably, the metallocene compound has the general formula Cp. x MA y Bz; wherein Cp is an unsubstituted cyclopentadienyl, a substituted cyclopentadienyl, an indenyl, a fluorenyl, an indenyl ligand in hydrogenated form, or a fluorenyl ligand in hydrogenated form; M is a transition metal zirconium or hafnium; A and B are halogen atoms, hydrogen atoms, or alkyl groups, respectively; x is an integer from 1 to 3; and y and z are integers from 1 to 3. Preferably, the metallocene compound has the general formula Cp. x MA y Bz; where Cp is n-propylcyclopentadienyl, M is the transition metal zirconium or hafnium, A and B are halogen atoms, hydrogen atoms or alkyl groups respectively, x is an integer from 1 to 3, and y and z are integers from 1 to 3; Preferably, the metallocene compound comprises bis(cyclopentadienyl)zirconia dichloride, bis(cyclopentadienyl)hafnium dichloride, bis(cyclopentadienyl)titanium dichloride, bis(cyclopentadienyl)dimethylzirconia, bis(cyclopentadienyl)dimethylhafnium, bis(n-propylcyclopentadienyl)zirconia dichloride, bis(n-propylcyclopentadienyl)hafnium dichloride, bis(n-propylcyclopentadienyl)dimethylzirconia, bis(n-propylcyclopentadienyl)dimethylhafnium, bis(n-butylcyclopentadienyl)zirconia dichloride, bis(n-butylcyclopentadienyl)hafnium dichloride, bis(n-butylcyclopentadienyl)di ... Titanium chloride, bis(n-butylcyclopentadienyl)dimethylzirconium, bis(n-butylcyclopentadienyl)dimethylhafnium, bis(dimethylcyclopentadienyl)dimethylzirconium, bis(tetramethylcyclopentadienyl)dimethylzirconium, diindylzirconium dichloride, diindylhafnium dichloride, bis(1-methyl-3-n-butylcyclopentadienyl)zirconium dichloride, bis(1-methyl-3-n-butylcyclopentadienyl)hafnium dichloride, isopropyl(cyclopentadienyl)(fluorenyl)zirconium dichloride, methylene-bridged diindylzirconium dichloride and bis(4,5,6,7-tetrahydro-1-indyl)zirconium dichloride, ethylene-bridged... Di(indenyl)zirconia, methylene-bridged diindenyl hafnium chloride and di(4,5,6,7-tetrahydro-1-indenyl)hafnium chloride, ethylene-bridged di(indenyl)hafnium chloride, ethylene-bridged di(indenyl)titanium chloride, di(4,5,6,7-tetrahydro-1-indenyl)titanium chloride, diphenylmethylene(cyclopentadienyl)(fluorenyl)zirconia, diphenylmethylene(cyclopentadienyl)(fluorenyl)hafnium chloride, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)zirconia, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)zirconia At least one of the following: hafnium chloride, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)dimethylzirconium, dimethylsilyl-bridged bis(2-methylindenyl)zirconium dichloride, dimethylsilyl-bridged bis(2-methyl-indenyl)hafnium dichloride, dimethylsilyl-bridged bis(2-methyl-benzo[a]indenyl)zirconium dichloride, dimethylsilyl-bridged bis(2-methyl-benzo[a]indenyl)hafnium dichloride, dimethylsilyl-bridged bis(2-methyl-benzo[a]indenyl)dimethylzirconium, dimethylsilyl-bridged bis(2-methyl-4-phenylindenyl)dimethylzirconium; Preferably, the metallocene compound comprises at least one of bis(n-propylcyclopentadienyl)zirconium dichloride, bis(n-propylcyclopentadienyl)hafnium dichloride, bis(n-propylcyclopentadienyl)dimethylzirconium, and bis(n-propylcyclopentadienyl)dimethylhafnium. Preferably, the mass ratio of the co-catalyst to the support is 1~5:5~10; Preferably, the mass ratio of the metallocene compound to the support is 0.5~2:40~60.

9. The application of a supported single-active-center catalyst as described in any one of claims 1-5 and / or a supported single-active-center catalyst prepared by the preparation method as described in any one of claims 6-8 in olefin polymerization; Preferably, the olefin polymerization includes ethylene homopolymerization, propylene homopolymerization, copolymerization of ethylene and propylene, or copolymerization of ethylene and α-olefins.

10. A method for preparing a high molecular weight polyolefin, characterized in that, The preparation method includes: using the supported single-active-center catalyst as described in any one of claims 1-5 and / or the supported single-active-center catalyst prepared by the preparation method as described in any one of claims 6-8 as a catalyst to carry out a polymerization reaction to obtain the high molecular weight polyolefin; Preferably, the preparation method comprises: using the supported single-active-center catalyst as described in any one of claims 1-5 and / or the supported single-active-center catalyst prepared by the preparation method as described in any one of claims 6-8 as the main catalyst, and an alkylaluminum compound as the co-catalyst, to carry out a polymerization reaction of olefin monomers in an organic medium, and filtering and drying the resulting product to obtain the high molecular weight polyolefin; preferably, the polymerization reaction includes any one of slurry polymerization, gas-phase polymerization or solution polymerization; Preferably, the alkylaluminum compound is at least one selected from trimethylaluminum, triethylaluminum, tri-n-propylaluminum, triisobutylaluminum, tri-n-butylaluminum, methylaluminoxane, modified methylaluminoxane, ethylaluminoxane, n-butylaluminoxane, or isopropylaluminoxane. Preferably, the olefin polymerization monomer includes at least one selected from ethylene, propylene, butene, pentene, hexene, octene, or 4-methyl-1-pentene; Preferably, the olefin polymerization reaction is carried out at a temperature of 0~100℃ for a time of 1~12h; Preferably, the organic medium is selected from at least one of tetrahydrofuran, diethyl ether, toluene, benzene, chloroform, dichloromethane, petroleum ether, n-hexane, and n-heptane.

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