Catalyst system for multistage olefin polymerization
Patent Information
- Application Number
- CN202580010840.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2024-01-22
- Filing Date
- 2025-01-22
- Publication Date
- 2026-08-28
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Abstract
Description
[0001] The present invention relates to a catalyst system for olefin polymerization, and more particularly, wherein the catalyst system is suitable for multi-stage olefin polymerization processes.
[0002] Today, olefin polymerization accounts for the majority of polymer material production processes worldwide. This process allows for the production of a wide variety of polyolefin materials, making the resulting polymers suitable for numerous applications.
[0003] To produce the desired polyolefin materials, several types of polymerization processes have been developed, each designed to produce polymers with specific molecular structures based on a formulation of specific monomer materials used as reactants. These polymerization processes can be operated using a single type of monomer material to obtain homopolymers, or using a combination of multiple monomer materials to obtain copolymers.
[0004] A significant portion of olefin polymerization processes involve the use of catalysts to accelerate the polymerization reaction. Over the past seventy years, numerous catalyst systems have been developed, most notably Ziegler-Natta, chromium-based, and monoparticle-based systems, with metallocene catalysts being particularly well-known. To this day, substantial work continues to develop these catalyst systems further to improve polymerization processes and the properties of the polymers that can be produced.
[0005] The most mature polyolefin materials are vinyl polymers and propylene polymers. Catalytic processes used to produce these polymers can be carried out in gas-phase, slurry, or solution reactions. In some advanced polymerization processes, olefin polymerization can be conducted using multi-stage processes, where polymerization occurs in multiple reactors arranged in series. By appropriately selecting process conditions, catalyst systems, and the monomer composition supplied to each reactor, polymers with customized molecular structures can be produced to meet the requirements of specific applications.
[0006] When applying such multi-stage polymerization processes, the specifications of the available catalyst systems can be particularly demanding. One aspect requiring special consideration when developing catalyst systems for such multi-stage olefin polymerization processes is the size of the catalyst particles. Excessively large particles can lead to overgrowth of polymer particles in later stages of polymerization. Simultaneously, the catalyst system must exhibit sufficient polymer productivity during the polymerization reaction and must produce polymers with the desired molecular weight.
[0007] Now, according to the present invention, this objective is achieved by a catalyst system for olefin polymerization, the catalyst system comprising a particulate support material loaded with a catalyst compound and a co-catalyst compound.
[0008] The particle size D50 of the particulate carrier material is ≤20 µm, preferably ≤15 µm, more preferably ≥5 µm and ≤15 µm, and is preferably silicon dioxide;
[0009] The particle size D50 is calculated according to ISO 9276-2 (2014) and measured using particle size measurements according to ISO 13320 (2009).
[0010] The cocatalyst compound is an organoaluminum compound, and
[0011] The catalyst system comprises, by weight, ≥20.0 wt% and ≤40.0 wt%, more preferably ≥25.0 wt% and ≤40.0 wt%, more preferably ≥20.0 wt% and ≤30.0 wt%, and even more preferably ≥25.0 wt% and ≤30.0 wt%.
[0012] This type of catalyst system combines small particle size (which is desirable for certain types of olefin polymerization processes, such as multi-stage polymerization) with high productivity, allowing for the production of polyethylene materials with appropriate molecular weights. This type of catalyst system can be used in gas-phase, solution, and slurry polymerization reactions.
[0013] The weight fraction of Al atoms in the catalyst system can be determined, for example, by inductively coupled plasma atomic emission spectrometry (ICP-AES).
[0014] The catalyst compound can be selected, for example, from Ziegler-Natta type catalyst compounds, chromium-containing catalyst compounds, and single-site type catalyst compounds such as metallocene catalyst compounds. When using metallocene compounds, such compounds can, for example, contain a zirconium dichloride structural moiety, a hafnium dichloride structural moiety, a titanium dichloride structural moiety, a dimethylzirconium structural moiety, a dimethylhafnium structural moiety, or a dimethyltitanium structural moiety. Preferably, such metallocene compounds contain a zirconium dichloride structural moiety.
[0015] In some embodiments, the catalyst compound may be a compound according to Formula I:
[0016] (I)
[0017] in:
[0018] Z is a structural moiety selected from ZrX2, HfX2 or TiX2, wherein X is selected from halogen, alkyl, aryl and aralkyl;
[0019] R2 is the bridge structure part;
[0020] R1, R1', R3, R3', R4, R4', R5, and R5' are each hydrogen or a hydrocarbon structural moiety containing 1 to 20 carbon atoms, or R1 and R5, R5 and R4, R4 and R3, R1' and R5', R5' and R4' and / or R4' and R3' are fused to form a cyclic hydrocarbon structural moiety containing 4 to 20 carbon atoms, preferably wherein the cyclic hydrocarbon structural moiety is a structural moiety containing a benzene ring structure, and the structural moiety may contain substituents containing 1 to 10 carbon atoms.
[0021] In compounds of formula (I), R2 can be, for example, selected from the following structural moieties:
[0022]
[0023] Each R6 is independently selected from H or an alkyl moiety containing 1-10 carbon atoms, preferably each R6 is independently selected from H, CH3 and phenyl moiety, more preferably each R6 is independently selected from H, CH3 and phenyl moiety, and each R6 is the same.
[0024] In the compound of formula (I), Z can be selected, for example, from TiCl2, ZrCl2, HfCl2, Ti(CH3)2, Zr(CH3)2 and Hf(CH3)2, preferably from ZrCl2 and Zr(CH3)2.
[0025] For example, each of R1, R3, R4, and R5 can be H or CH3.
[0026] For example, R3' and R4', or R4' and R5', or R3' and R4' and R5' and R1' can be fused together to form a cyclic structure containing a benzene ring structure. For example, R3 and R4, or R4 and R5, or R3 and R4 and R5 and R1 can be fused together to form a cyclic structure containing a benzene ring structure.
[0027] In a particular embodiment, the catalyst compound may be selected from the following compounds:
[0028] [2,2'-bis(2-indene)biphenyl]zirconium dichloride, [2,2'-bis(4,7-dimethyl-2-indene)biphenyl]zirconium dichloride, [[(1,2,3,3a,7a-η)-2-(1-methylethyl)-1H-indene-1-yl](dimethylmethylenesilyl)[(1,2,3,4,5-η)-2,3,4,5-tetramethyl-2,4-cyclopentadien-1-yl]]zirconium dichloride, diphenylmethylene-(1-cyclopentadienyl)(2,7-di-tert-butyl-9-fluorenyl)-zirconium dichloride;
[0029] [2,2'-bis(2-indene)biphenyl]dimethylzirconium, [2,2'-bis(4,7-dimethyl-2-indene)biphenyl]dimethylzirconium, [[(1,2,3,3a,7a-η)-2-(1-methylethyl)-1H-indene-1-yl](dimethylmethylenesilyl)[(1,2,3,4,5-η)-2,3,4,5-tetramethyl-2,4-cyclopentadien-1-yl]]dimethylzirconium, diphenylmethylene-(1-cyclopentadienyl)(2,7-di-tert-butyl-9-fluorenyl)-dimethylzirconium;
[0030] [2,2'-bis(2-indene)biphenyl] hafnium chloride, [2,2'-bis(4,7-dimethyl-2-indene)biphenyl] hafnium chloride, [[(1,2,3,3a,7a-η)-2-(1-methylethyl)-1H-indene-1-yl](dimethylmethylenesilyl)[(1,2,3,4,5-η)-2,3,4,5-tetramethyl-2,4-cyclopentadien-1-yl]] hafnium chloride, diphenylmethylene-(1-cyclopentadienyl)(2,7-di-tert-butyl-9-fluorenyl)-hafnium chloride;
[0031] [2,2'-bis(2-indyl)biphenyl]dimethylhafnium, [2,2'-bis(4,7-dimethyl-2-indyl)biphenyl]dimethylhafnium, [[(1,2,3,3a,7a-η)-2-(1-methylethyl)-1H-indyl](dimethylmethylenesilyl)[(1,2,3,4,5-η)-2,3,4,5-tetramethyl-2,4-cyclopentadien-1-yl]]dimethylhafnium, diphenylmethylene-(1-cyclopentadienyl)(2,7-di-tert-butyl-9-fluorenyl)-dimethylhafnium;
[0032] [2,2'-bis(2-indene)biphenyl]titanium chloride, [2,2'-bis(4,7-dimethyl-2-indene)biphenyl]titanium chloride, [[(1,2,3,3a,7a-η)-2-(1-methylethyl)-1H-indene-1-yl](dimethylmethylenesilyl)[(1,2,3,4,5-η)-2,3,4,5-tetramethyl-2,4-cyclopentadien-1-yl]]titanium chloride, diphenylmethylene-(1-cyclopentadienyl)(2,7-di-tert-butyl-9-fluorenyl)-titanium chloride;
[0033] [2,2'-bis(2-indene)biphenyl]dimethyltitanium, [2,2'-bis(4,7-dimethyl-2-indene)biphenyl]dimethyltitanium, [[(1,2,3,3a,7a-η)-2-(1-methylethyl)-1H-indene-1-yl](dimethylmethylenesilyl)[(1,2,3,4,5-η)-2,3,4,5-tetramethyl-2,4-cyclopentadien-1-yl]]dimethyltitanium, and diphenylmethylene-(1-cyclopentadienyl)(2,7-di-tert-butyl-9-fluorenyl)-dimethyltitanium.
[0034] Particularly preferred are catalyst compounds selected from [2,2'-bis(2-indenyl)biphenyl]zirconium chloride, [2,2'-bis(4,7-dimethyl-2-indenyl)biphenyl]zirconium chloride, [[(1,2,3,3a,7a-η)-2-(1-methylethyl)-1H-inden-1-yl](dimethylmethylenesilyl)[(1,2,3,4,5-η)-2,3,4,5-tetramethyl-2,4-cyclopentadien-1-yl]]zirconium chloride, and diphenylmethylene-(1-cyclopentadienyl)(2,7-di-tert-butyl-9-fluorenyl)-zirconium chloride.
[0035] Preferably, the organoaluminum compound is methylaluminoxane.
[0036] The molar ratio of the co-catalyst to the catalyst compound can be, for example, in the range of 1:1 to 2000:1, preferably in the range of 50:1 to 500:1.
[0037] The carrier material can be, for example, a material selected from silica, alumina, magnesium oxide, titanium dioxide, zirconium oxide, clay, zeolite, polystyrene, polyethylene, polypropylene, polyvinyl chloride, polycarbonate, polyketone, polyvinyl alcohol, polymethyl methacrylate, cellulose, graphite, and mixtures thereof. Preferably, the carrier material is silica.
[0038] The carrier material, preferably silica, has a specific surface area of 50 to 1000 m². 2 / g particles. Preferably, this type of silica is dehydrated at a temperature of ≥400°C, preferably ≥400°C and ≤700°C, more preferably ≥550°C and ≤700°C for ≥2 and ≤8 hours, preferably ≥4 and ≤8 hours. This dehydration is preferably carried out under a nitrogen atmosphere.
[0039] In one embodiment, the invention also relates to a method for producing a catalyst system according to the invention, wherein the method comprises the following steps in sequence:
[0040] (i) Providing a carrier material with a particle size D50 ≤ 20 µm, preferably ≤ 15 µm, more preferably ≥ 5 µm and ≤ 15 µm, preferably silica, to the first container; preferably wherein the silica has been dehydrated at a temperature of ≥ 400°C for ≥ 2 and ≤ 8 hours before being provided to step (i);
[0041] (ii) Add a certain amount of suspending agent to the first container;
[0042] (iii) A certain amount of catalyst compound and a certain amount of co-catalyst are supplied to the second container and mixed to obtain an activated catalyst compound;
[0043] (iv) The activated catalyst compound is supplied to the first container and reacted with the silica to obtain the catalyst system.
[0044] Step (iii) of the method may include adding a certain amount of catalyst modifier, preferably wherein the catalyst modifier is the reaction product of a trialkylaluminum compound and an alkylamine compound.
[0045] The catalyst system according to the invention can be prepared alternatively by contacting a support material, preferably silica, with a co-catalyst, followed by adding a catalyst compound; or by contacting the catalyst compound with the co-catalyst first, followed by adding the support material; or by contacting the support material with the co-catalyst first, followed by adding a certain amount of a product containing the catalyst compound, which has been previously contacted with another portion of the co-catalyst.
[0046] Such trialkylaluminum compounds may be selected, for example, from trimethylaluminum, triethylaluminum, triisopropylaluminum and triisobutylaluminum, with triisobutylaluminum being preferred.
[0047] Such alkylamine compounds can be selected, for example, from cyclohexylamine, octadecylamine and ethylhexylamine, with cyclohexylamine being preferred.
[0048] Preferably, the trialkylaluminum compound is triisobutylaluminum, and the alkylamine compound is cyclohexylamine.
[0049] The present invention also relates to a method for olefin polymerization, wherein polymerization is carried out in the presence of a catalyst system according to the invention. Preferably, the method is a multi-stage polymerization process comprising at least a first reactor and a second reactor operating in series.
[0050] The olefins that can be used in the polymerization method according to the invention can be selected, for example, from ethylene, propylene, 1-butene, 1-hexene, 1-octene, and combinations thereof. Preferred polymers obtained by the olefin polymerization method according to the invention are vinyl polymers and propylene polymers.
[0051] When the polymerization is intended to produce a vinyl polymer, the monomer composition supplied to the polymerization process comprises at least 51 wt% ethylene by total weight of the monomers supplied to the process. This monomer composition may comprise at least 51 wt%, preferably at least 60 wt%, more preferably at least 70 wt%, or at least 80 wt% ethylene, wherein the remainder comprises one or more of propylene, 1-butene, 1-hexene, or 1-octene, or combinations thereof.
[0052] In an embodiment of this method as a multi-stage process for producing vinyl polymers, the monomer compositions in each reactor can be different. For example, the monomer composition supplied to the first reactor can be composed of ethylene, or can be composed of ethylene and one or more other olefins selected from propylene, 1-butene, 1-hexene, and 1-octene; and the monomer composition supplied to the second reactor can be composed of ethylene, or can be composed of ethylene and one or more other olefins selected from propylene, 1-butene, 1-hexene, and 1-octene.
[0053] When the polymerization is intended to produce a propylene-based polymer, the monomer composition supplied to the polymerization process comprises at least 51 wt% propylene by total weight of the monomers supplied to the process. This monomer composition may comprise at least 51 wt%, preferably at least 60 wt%, more preferably at least 70 wt%, or at least 80 wt% propylene, wherein the remainder comprises one or more of ethylene, 1-butene, 1-hexene, or 1-octene, or combinations thereof.
[0054] In an embodiment of this method as a multi-stage process for producing propylene-based polymers, the monomer compositions in each reactor can be different. For example, the monomer composition supplied to the first reactor can be composed of propylene, or can be composed of propylene and one or more other olefins selected from ethylene, 1-butene, 1-hexene, and 1-octene; and the monomer composition supplied to the second reactor can be composed of propylene, or can be composed of propylene and one or more other olefins selected from ethylene, 1-butene, 1-hexene, and 1-octene.
[0055] The first reactor can be, for example, a slurry reactor or a gas-phase reactor, and the second reactor can be, for example, a slurry reactor or a gas-phase reactor. Preferably, the first reactor is a slurry reactor and the second reactor is a slurry reactor, or the first reactor is a slurry reactor and the second reactor is a gas-phase reactor, or the first reactor is a gas-phase reactor and the second reactor is a gas-phase reactor.
[0056] When polymerization is carried out in a gas-phase reactor, such reactors are preferably operated in condensation or ultracondensation mode. Preferably, the gas-phase reactor used for polymerization according to the present invention is a fluidized bed reactor.
[0057] When polymerization is carried out in a slurry reactor, a batch reactor or a loop reactor is preferred.
[0058] The present invention will now be described through the following non-limiting embodiments.
[0059] Materials used in the experiment
[0060] The materials used in the experiments used to demonstrate the present invention are listed in Table 1 below.
[0061] Table 1: Materials used.
[0062]
[0063] All materials were treated under a nitrogen atmosphere using the Schlenk technique or a nitrogen-filled glove box. Nitrogen, isopentane, and other solvents were dried over a molecular sieve bed. The catalyst system was prepared in a stirred silicone oil bath under conditions controlled within 0.5°C of the set temperature.
[0064] Preparation of supported metallocene catalyst systems
[0065] Various supported metallocene catalyst systems were prepared according to the following procedure. Details of the amounts and properties of the materials used, as well as the contents of Zr and Al in the catalyst systems, are shown in Table 2.
[0066] The support was pre-dehydrated at 600°C for 4 hours. In a glove box under nitrogen atmosphere, a given amount of the pre-dehydrated support was placed into a 100 ml double-necked Schlenk flask, followed by the addition of 15 ml of toluene. After shaking, a silica suspension was obtained. The metallocene catalyst compound was activated in a glove box under nitrogen atmosphere by mixing a given amount of the metallocene catalyst compound with a given amount of the co-catalyst in a 25 ml vial at room temperature for 10 min. The amount of the metallocene catalyst compound was selected to achieve the desired Zr wt% in the catalyst system. The resulting activated metallocene was transferred to the silica suspension. In a glove box, 3.64 mg of CHA and 7.28 mg of TIBAL were mixed in 10 ml of toluene in another 25 ml vial at room temperature, and then transferred to the suspension. The final mixture was heated to 95°C and maintained at this temperature for 5 hours. Subsequently, the product was vacuum dried at 75°C to obtain the supported catalyst system, which was separated as a free-flowing powder.
[0067] Table 2: Composition of the catalyst system
[0068]
[0069] Catalyst systems A1-A4 were prepared using larger silica S1, thus resulting in catalyst system particles with larger particle sizes compared to catalyst systems A5-A12 prepared using smaller silica S2.
[0070] Polymerization Experiment
[0071] A series of polymerization experiments were conducted using catalyst systems A1-A12 to determine the performance of each catalyst system in ethylene polymerization.
[0072] A 1.6 L stainless steel reaction vessel equipped with a spiral stirrer and a heating / cooling control unit was heated to 110°C at a nitrogen flow rate of 100 g / h and held for 2 hours. Afterward, the reactor was pressure purged with nitrogen, followed by ethylene purging. This purging cycle was repeated three times.
[0073] The reactor was then cooled to 88°C under ethylene pressure of 10 bar.
[0074] For gas-phase polymerization experiments B1-B12, after venting, 4 ml of AXION® PA4276 was added via a co-catalyst injection pump. Nitrogen was introduced to maintain a nitrogen pressure of 8 bar. Ethylene was then introduced into the reactor under controlled mass flow rate parameters to maintain an ethylene pressure of 10 bar. After reaching stable temperature and pressure levels, 40 mg of catalyst was injected via a catalyst injection pump, and the reaction began. After 1 hour, the ethylene supply was stopped, and the reactor was cooled to 40°C. The reactor was then opened after venting. The polyethylene product was collected in a sample pan and dried at ambient temperature and atmospheric pressure.
[0075] For slurry polymerization experiments B13-B16, after evacuation, 200 ml of isopentane was injected via a co-catalyst injection pump, followed by the addition of 4 ml of diluted AXION® PA 4276. Nitrogen was introduced to maintain a nitrogen pressure of 3 bar. Ethylene was then introduced into the reactor under controlled flow rate parameters to maintain an ethylene pressure of 10 bar. After reaching stable temperature and pressure levels, 40 mg of catalyst was injected via the catalyst injection pump, and the reaction began. After 1 hour, the ethylene supply was stopped, and the reactor was cooled to 40°C. The reactor was then opened after evacuation. The polyethylene product was collected in a sample pan and dried at ambient temperature and atmospheric pressure.
[0076] The aggregation results are shown in Table 3 below.
[0077] Table 3: Results of the polymerization experiment
[0078]
[0079] In this table, PE yield is expressed as the weight of polyethylene obtained in the experiment, in grams; productivity is defined as the weight of polyethylene obtained per unit weight of catalyst system supplied, in g PE / g Cat. n M is the number average molecular weight. w Both are weight-average molecular weights, expressed in kg / mol, and determined according to ASTM D6474 (2012). w / M n For M w With M n The ratio is dimensionless and represents the molecular weight distribution.
[0080] As shown in Table 3, by employing an increased Al content, catalyst systems can achieve relatively small particle sizes (which is desirable for certain types of olefin polymerization processes, such as multi-stage polymerization) while still maintaining high productivity and allowing the production of polyethylene materials with appropriate molecular weights. Such catalyst systems can be used in both gas-phase and slurry polymerization reactions.
Claims
1. A catalyst system for olefin polymerization, comprising a particulate support material loaded with a catalyst compound and a co-catalyst compound. The particle size D50 of the particulate carrier material is ≤20 µm, preferably ≤15 µm, more preferably ≥5 µm and ≤15 µm, and is preferably silicon dioxide; The particle size D50 was calculated according to ISO 9276-2 (2014) and measured using particle size according to ISO 13320 (2009). The co-catalyst compound is an organoaluminum compound; and The catalyst system contains ≥20.0 wt%, preferably ≥20.0 wt% and ≤40.0 wt%, more preferably ≥25.0 wt% and ≤40.0 wt%, more preferably ≥20.0 wt% and ≤30.0 wt%, and even more preferably ≥25.0 wt% and ≤30.0 wt% of Al atoms, based on the total weight of the catalyst system.
2. The catalyst system according to claim 1, wherein the catalyst compound is selected from Ziegler-Natta type catalyst compounds, chromium-containing catalyst compounds, and single-site catalyst compounds, such as metallocene catalyst compounds.
3. The catalyst system according to any one of claims 1-2, wherein the catalyst compound is a metallocene-type catalyst compound, preferably a compound containing zirconium dichloride.
4. The catalyst system according to any one of claims 1-3, wherein the catalyst compound is a compound according to formula I: in: Z is a structural moiety selected from ZrX2, HfX2 or TiX2, wherein X is selected from halogen, alkyl, aryl and aralkyl; R2 is the bridge structure part; R1, R1', R3, R3', R4, R4', R5, and R5' are each hydrogen or a hydrocarbon structural moiety containing 1 to 20 carbon atoms, or R1 and R5, R5 and R4, R4 and R3, R1' and R5', R5' and R4' and / or R4' and R3' are fused to form a cyclic hydrocarbon structural moiety containing 4 to 20 carbon atoms, preferably wherein the cyclic hydrocarbon structural moiety is a structural moiety containing a benzene ring structure, and the structural moiety may contain substituents containing 1 to 10 carbon atoms.
5. The catalyst system according to claim 4, wherein R2 is selected from the following structural parts: Each R6 is independently selected from H or an alkyl moiety containing 1-10 carbon atoms, preferably each R6 is independently selected from H, CH3 and phenyl moiety, more preferably each R6 is independently selected from H, CH3 and phenyl moiety, and each R6 is the same.
6. The catalyst system according to any one of claims 4-5, wherein Z is selected from TiCl2, ZrCl2, HfCl2, Ti(CH3)2, Zr(CH3)2 and Hf(CH3)2, preferably selected from ZrCl2 and Zr(CH3)2.
7. The catalyst system according to any one of claims 4-6, wherein: Each of R1, R3, R4, and R5 is H or CH3; and / or R3' and R4', or R4' and R5', or R3' and R4' and R5' and R1' are fused together to form a cyclic structure containing a benzene ring structure; and / or R3 and R4, or R4 and R5, or R3 and R4 and R5 and R1 are fused together to form a cyclic structure containing a benzene ring structure.
8. The catalyst system according to any one of claims 1-7, wherein the catalyst compound is selected from the group consisting of: [2,2'-bis(2-indene)biphenyl]zirconium dichloride, [2,2'-bis(4,7-dimethyl-2-indene)biphenyl]zirconium dichloride, [[(1,2,3,3a,7a-η)-2-(1-methylethyl)-1H-indene-1-yl](dimethylmethylenesilyl)[(1,2,3,4,5-η)-2,3,4,5-tetramethyl-2,4-cyclopentadien-1-yl]]zirconium dichloride, diphenylmethylene-(1-cyclopentadienyl)(2,7-di-tert-butyl-9-fluorenyl)-zirconium dichloride; [2,2'-bis(2-indene)biphenyl]dimethylzirconium, [2,2'-bis(4,7-dimethyl-2-indene)biphenyl]dimethylzirconium, [[(1,2,3,3a,7a-η)-2-(1-methylethyl)-1H-indene-1-yl](dimethylmethylenesilyl)[(1,2,3,4,5-η)-2,3,4,5-tetramethyl-2,4-cyclopentadien-1-yl]]dimethylzirconium, diphenylmethylene-(1-cyclopentadienyl)(2,7-di-tert-butyl-9-fluorenyl)-dimethylzirconium; [2,2'-bis(2-indene)biphenyl] hafnium chloride, [2,2'-bis(4,7-dimethyl-2-indene)biphenyl] hafnium chloride, [[(1,2,3,3a,7a-η)-2-(1-methylethyl)-1H-indene-1-yl](dimethylmethylenesilyl)[(1,2,3,4,5-η)-2,3,4,5-tetramethyl-2,4-cyclopentadien-1-yl]] hafnium chloride, diphenylmethylene-(1-cyclopentadienyl)(2,7-di-tert-butyl-9-fluorenyl)-hafnium chloride; [2,2'-bis(2-indyl)biphenyl]dimethylhafnium, [2,2'-bis(4,7-dimethyl-2-indyl)biphenyl]dimethylhafnium, [[(1,2,3,3a,7a-η)-2-(1-methylethyl)-1H-indyl](dimethylmethylenesilyl)[(1,2,3,4,5-η)-2,3,4,5-tetramethyl-2,4-cyclopentadien-1-yl]]dimethylhafnium, diphenylmethylene-(1-cyclopentadienyl)(2,7-di-tert-butyl-9-fluorenyl)-dimethylhafnium; [2,2'-bis(2-indene)biphenyl]titanium chloride, [2,2'-bis(4,7-dimethyl-2-indene)biphenyl]titanium chloride, [[(1,2,3,3a,7a-η)-2-(1-methylethyl)-1H-indene-1-yl](dimethylmethylenesilyl)[(1,2,3,4,5-η)-2,3,4,5-tetramethyl-2,4-cyclopentadien-1-yl]]titanium chloride, diphenylmethylene-(1-cyclopentadienyl)(2,7-di-tert-butyl-9-fluorenyl)-titanium chloride; [2,2'-bis(2-indene)biphenyl]dimethyltitanium, [2,2'-bis(4,7-dimethyl-2-indene)biphenyl]dimethyltitanium, [[(1,2,3,3a,7a-η)-2-(1-methylethyl)-1H-indene-1-yl](dimethylmethylenesilyl)[(1,2,3,4,5-η)-2,3,4,5-tetramethyl-2,4-cyclopentadien-1-yl]]dimethyltitanium, and diphenylmethylene-(1-cyclopentadienyl)(2,7-di-tert-butyl-9-fluorenyl)-dimethyltitanium; The preferred materials are zirconium dichloride selected from [2,2'-bis(2-indene)biphenyl], zirconium dichloride selected from [2,2'-bis(4,7-dimethyl-2-indene)biphenyl], zirconium dichloride selected from [[(1,2,3,3a,7a-η)-2-(1-methylethyl)-1H-indene-1-yl](dimethylmethylenesilyl)[(1,2,3,4,5-η)-2,3,4,5-tetramethyl-2,4-cyclopentadien-1-yl]], and diphenylmethylene-(1-cyclopentadienyl)(2,7-di-tert-butyl-9-fluorenyl)-zirconium dichloride.
9. The catalyst system according to any one of claims 1-8, wherein the organoaluminum compound is methylaluminoxane.
10. A method for producing a catalyst system according to any one of claims 1-9, wherein the method comprises the following steps in sequence: (i) Provide a carrier material with a particle size D50 ≤ 20 µm, preferably ≤ 15 µm, more preferably ≥ 5 µm and ≤ 15 µm, preferably silica, to the first container; preferably wherein the silica has been dehydrated at a temperature of ≥ 400°C for ≥ 2 and ≤ 8 hours before being provided to step (i); (ii) Add a certain amount of suspending agent to the first container; (iii) A certain amount of catalyst compound and a certain amount of co-catalyst are supplied to the second container and mixed to obtain an activated catalyst compound; (iv) The activated catalyst compound is supplied to the first container and reacted with silica to obtain the catalyst system.
11. The method according to claim 10, wherein step (iii) further comprises adding a certain amount of catalyst modifier, preferably wherein the catalyst modifier is the reaction product of a trialkylaluminum compound and an alkylamine compound.
12. The method according to claim 11, wherein the trialkylaluminum compound is selected from trimethylaluminum, triethylaluminum, triisopropylaluminum and triisobutylaluminum, preferably triisobutylaluminum; and / or wherein the alkylamine compound is selected from cyclohexylamine, octadecylamine and ethylhexylamine, preferably cyclohexylamine.
13. An olefin polymerization method, wherein polymerization is carried out in the presence of a catalyst system according to any one of claims 1-9, preferably wherein the method is a multi-stage polymerization process comprising at least a first reactor and a second reactor operating in series.
14. The method of claim 13, wherein the first reactor is a slurry reactor or a gas phase reactor, and wherein the second reactor is a slurry reactor or a gas phase reactor.
15. The method according to any one of claims 13-14, wherein the first reactor is a slurry reactor and the second reactor is a slurry reactor, or wherein the first reactor is a slurry reactor and the second reactor is a gas phase reactor, or wherein the first reactor is a gas phase reactor and the second reactor is a gas phase reactor.