A catalyst component for ethylene polymerization reaction, preparation method and application

Abstract

The present application relates to the technical field of catalyst for preparing olefin polymer, in particular to a catalyst component for ethylene polymerization reaction and preparation method and application. The catalyst component comprises the reaction product of the following components: at least one mesoporous material carrier, at least one magnesium compound, at least one titanium compound, at least one alcohol ether compound and at least one ether compound; wherein the mesoporous material carrier has a two-dimensional hexagonal channel structure, the average pore size of the mesoporous material carrier is 4-15 nm, the specific surface area is 550-650 m 2 / g, the pore volume is 0.5-1.5 mL / g, and the average particle size is 0.5-10 μm. The catalyst component has high catalytic activity when it is used for ethylene homopolymerization or copolymerization, and the prepared polymer powder has high bulk density and narrow polymer molecular weight distribution.

Description

Technical Field

[0001] This invention relates to the field of catalysts for the preparation of olefin polymers, specifically to a catalyst component, preparation method, and application for ethylene polymerization. Background Technology

[0002] Currently, the Ziegler-Natta catalyst system based on Ti / Mg composites still dominates the industrial production of polyethylene. Technicians in this field are dedicated to developing effective methods to achieve two key objectives: firstly, to obtain catalysts with sufficiently high polymerization activity, ensuring high efficiency in the production process while minimizing residue in the polymer; and secondly, to obtain polymer particles with uniform distribution, near-spherical morphology, and low content of fine polymer powder, facilitating long-term continuous operation of industrial plants. To obtain favorable particle morphology, technicians often employ a loading method to prepare catalysts, impregnating the active catalyst component onto a particulate support material, such as porous inorganic support materials like silica or organic particulate support materials. For example, US4293673, US4303771, US4302565, US4302566, and EP0835887A2 disclose the preparation of catalysts by supporting magnesium compounds and titanium compounds on inorganic supports. The morphology of the support determines the morphology of the final catalyst. This preparation method has high requirements for the morphology and surface properties of the support, which leads to an increase in the cost of catalyst preparation. In addition, the disadvantage of supported catalysts is that the impregnation step may cause uneven loading of active components on the support surface. At the same time, the limited specific surface area of ​​the support restricts the loading amount, thereby limiting the improvement of catalyst activity.

[0003] In industrial production, the bulk density of polymer powder is also a very important parameter. Industrially, increasing the bulk density of polymers allows for longer catalyst residence times, which is beneficial for increasing reactor output and achieving better reactor operability.

[0004] Furthermore, Ziegler-Natta catalysts typically employ various active centers, resulting in polyethylene resins with a wide molecular weight distribution. Given a fixed polymer molecular weight, narrowing this distribution leads to a more uniform distribution of comonomers and improved transparency in the resulting film. When the average molecular weight of the resin is the same, a narrower molecular weight distribution results in higher impact strength. Industrially, the molecular weight distribution is typically altered by changing the process flow or catalyst system. However, controlling the molecular weight distribution through process modifications is limited by the process itself. Changing the type and state of the catalyst is an effective way to control the molecular weight distribution.

[0005] The catalyst particles obtained in US patents US3787384A, US4148754A, US4173547A, and US4508843A have unsatisfactory morphology, with a wide or even multi-peak distribution, which is detrimental to the long-term stable operation of the polymerization unit. US20060172883A1, US20040259723A1, US20040010101A1, and US20040010100A1, among others, use inorganic materials with extremely small average particle sizes, such as silica gel, to spray-dry the catalyst active components together to prepare the catalyst. CN1085915A discloses a method for preparing a Ziegler-Natta catalyst system. TiCl3 tetrahydrofuran solution is prepared by reducing titanium tetrachloride with metallic magnesium in tetrahydrofuran. Then, magnesium chloride is dissolved in tetrahydrofuran. The two solutions are thoroughly mixed, and unreacted magnesium and undissolved magnesium chloride are filtered out. The filtered solution is thoroughly mixed with silica gel and then spray-dried to obtain dispersed catalyst particles. This preparation method generates a lot of waste residue, requires a filtration step, and increases the post-processing steps and costs.

[0006] Therefore, there is a need for a catalyst suitable for ethylene polymerization that not only has high catalytic activity but also good catalyst particle morphology, so that the prepared polymer powder has a high polymer packing density and a narrow polymer molecular weight distribution. Summary of the Invention

[0007] The purpose of this invention is to overcome the limitations of existing polyolefin catalysts, such as the pore structure of the support and the solubility of the supported components, resulting in low effective loading of the active catalyst component on the support, and consequently, low catalytic activity of supported polyolefin catalysts prepared from existing supported polyolefin catalyst supports. This invention exhibits high catalytic activity and a narrow polymer molecular weight distribution when used for homopolymerization or copolymerization of ethylene. It provides a method for preparing a polyolefin catalyst, a polyolefin catalyst prepared by the above method, the application of the polyolefin catalyst prepared by the above method in olefin monomer polymerization reactions, and the polyolefin obtained by the method.

[0008] A first aspect of the present invention is to provide a catalyst component comprising a reaction product of the following components:

[0009] At least one mesoporous material carrier, at least one magnesium compound, at least one titanium compound, at least one alcohol ether compound, and at least one ether compound;

[0010] The mesoporous material carrier has a two-dimensional hexagonal channel structure, with an average pore size of 4-15 nm and a specific surface area of ​​550-650 m². 2 / g, pore volume is 0.5-1.5mL / g, and average particle size is 0.5-10μm.

[0011] In a preferred embodiment of the present invention, the mesoporous material carrier is prepared by the following method:

[0012] (a) In the presence of a template agent, a silicon source and an acid agent are mixed and contacted, and the mixture obtained after mixing and contact is crystallized, filtered and dried in sequence to obtain mesoporous material powder;

[0013] (b) The mesoporous material powder is subjected to template release agent treatment, thermal activation treatment and ball milling treatment in sequence to obtain a mesoporous material carrier.

[0014] According to the present invention, in step (a), the type of template agent is not particularly limited. Preferably, the template agent can be a polyoxyethylene-polyoxypropylene-polyoxyethylene triblock copolymer, which can be commercially available (e.g., it can be purchased from Aldrich under the trade name P123, with the molecular formula EO). 20 PO 70 EO 20 It can also be prepared using various existing methods.

[0015] The acid can be any of the acidic aqueous solutions commonly used in the art, for example, it can be an aqueous solution of at least one of hydrochloric acid, sulfuric acid, nitric acid and hydrobromic acid, preferably an aqueous solution of hydrochloric acid.

[0016] The amount of acid is not particularly limited and can vary within a wide range. Preferably, the pH value of the mixture contact is 1-6.

[0017] In a preferred embodiment, the mixing contact conditions in step (a) include: a temperature of 25-60°C, a time of 25 minutes or more, and a pH of 1-6. To further facilitate uniform mixing of the substances, according to a preferred embodiment of the invention, the mixing contact is carried out under stirring conditions.

[0018] In this invention, the silicon source can be any silicon source conventionally used in the art, preferably at least one of tetraethyl orthosilicate, methyl orthosilicate, propyl orthosilicate, sodium orthosilicate and silica sol, more preferably tetraethyl orthosilicate.

[0019] In this invention, the amounts of the template agent and the silicon source can vary within a wide range. In a preferred embodiment of this invention, the molar ratio of the template agent and the silicon source is 1:(10-90), preferably 1:(50-75).

[0020] According to a preferred embodiment of the present invention, the process of mixing and contacting the silicon source and the acid agent in the presence of the template agent includes: adding the template agent triblock copolymer polyoxyethylene-polyoxypropylene-polyoxyethylene P123 to an aqueous solution of hydrochloric acid at a molar ratio of triblock copolymer polyoxyethylene-polyoxypropylene-polyoxyethylene P123:water:hydrogen chloride = 1:9000-15000:100-500, stirring at 25-60°C until dissolved, and then adding the silicon source tetraethyl orthosilicate to the above-obtained solution at a molar ratio of triblock copolymer polyoxyethylene-polyoxypropylene-polyoxyethylene P123:tetraethyl orthosilicate = 1:50-75, and stirring at 25-60°C for more than 25 minutes.

[0021] In a preferred embodiment of the present invention, the crystallization conditions include a temperature of 90-180°C and a time of 10-40 hours. According to a preferred embodiment, the crystallization is carried out by a hydrothermal crystallization method. To ensure that a mesoporous molecular sieve material with a sufficiently large pore size is obtained, the crystallization conditions are further preferably a temperature of 130-180°C.

[0022] Preferably, the filtration process may include: after filtration, repeatedly washing with deionized water (the number of washings may be 2-10), and then performing vacuum filtration.

[0023] Preferably, the drying can be carried out in a drying oven, and the drying conditions may include: a temperature of 110-150°C and a time of 3-6 hours.

[0024] Preferably, in step (b), the method for removing the template agent is an alcohol washing method. In a more preferred embodiment of the present invention, in step (b), the process of removing the template agent includes: washing the mesoporous material powder with alcohol, preferably at 90-120°C, and washing the mesoporous material powder with alcohol for 10-40 hours.

[0025] According to the present invention, in step (b), in order to remove the hydroxyl groups and residual moisture from the mesoporous material carrier, a thermal activation treatment is required before loading the metal component onto the mesoporous material carrier. The conditions for the thermal activation treatment may include: calcining the mesoporous material carrier at a temperature of 300-900°C for 7-10 hours in the presence of nitrogen.

[0026] According to the present invention, in step (b), the specific operation method and conditions of the ball milling treatment are based on not damaging or substantially not damaging the pore structure of the mesoporous material with a two-dimensional hexagonal structure. Those skilled in the art can select various suitable conditions to implement the present invention based on the above principles. Specifically, the ball milling treatment can be carried out in a ball mill, wherein the diameter of the grinding balls in the ball mill can be 2-3 mm; the number of grinding balls can be reasonably selected according to the size of the grinding jar; for a grinding jar of 50-150 mL, 20-80 grinding balls can usually be used; the material of the grinding balls can be agate, polytetrafluoroethylene, etc., preferably agate. The ball milling conditions include: the rotational speed of the grinding balls can be 300-500 r / min, the temperature inside the grinding jar can be 15-100℃, and the ball milling time can be 0.1-100 hours. In a preferred embodiment, step (b) is carried out under nitrogen protection. Dichlorodimethylsilane may be added during the ball milling process to further remove hydroxyl groups from the surface of the mesoporous carrier. The ball milling conditions result in an average particle diameter of 0.5-10 μm for the mesoporous material carrier obtained by ball milling.

[0027] The mesoporous material carrier has a two-dimensional hexagonal channel structure, with an average pore size of 4-15 nm and a specific surface area of ​​550-650 m². 2 / g, pore volume is 0.5-1.5mL / g, and average particle size is 0.5-10μm.

[0028] In a preferred embodiment, the mesoporous material has an average pore size of 4-12 nm, such as 4 nm, 5 nm, 6 nm, 7 nm, 8 nm, 9 nm, 10 nm, 11 nm, and 12 nm, or any average pore size within a range formed by any two average pore sizes, and a specific surface area of ​​580-620 m². 2 The pore volume is 0.5-1 mL / g, and the average particle size is 0.5-10 μm. This ensures that the mesoporous material has the advantages of large pore size, large pore volume, and large specific surface area, which is more conducive to the good dispersion of magnesium and / or titanium active components on the surface of the mesoporous material. In turn, it can ensure that the polyolefin catalyst prepared from it has excellent catalytic performance.

[0029] According to the present invention, the magnesium compound can be selected from a wide range, and in a preferred embodiment of the present invention, the magnesium compound is selected from the formula Mg(OR1). m Cl 2-m One or more of the compounds shown, wherein R1 is C2-C 20 hydrocarbon group or C3-C 20 Cyclic hydrocarbon groups, preferably C2-C 10The alkyl group, 0≤m≤2, preferably, the magnesium compound is selected from at least one of magnesium diethoxy, magnesium dipropoxy, magnesium dibutoxy, magnesium dioctyloxy, and magnesium dichloride.

[0030] According to the present invention, the titanium compound can be selected from a wide range. In a preferred embodiment of the present invention, the titanium compound is selected from one or more titanium halides, preferably from one or more titanium chloride and titanium bromide, and more preferably from one or two titanium trichloride and titanium tetrachloride.

[0031] According to the present invention, the alcohol ether compound can be selected from a wide range. In a preferred embodiment of the present invention, the alcohol ether compound is selected from one or more of the lower carbon alcohol ethers of ethylene glycol and the lower carbon alcohol ethers of propylene glycol, preferably from one or more of propylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monomethyl ether, ethylene glycol monopropyl ether, propylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monobutyl ether, and propylene glycol monopropyl ether.

[0032] According to the present invention, the ether compound can be selected from a wide range. In a preferred embodiment of the present invention, the ether compound is selected from one or more of anisole, phenethyl ether, propyl ether, butyl ether, isopropyl ether, isobutyl ether, 1,4-dioxane, tetrahydrofuran, methyltetrahydrofuran, ethylene oxide, 1,2-epoxypropane, 1,2-epoxybutane, cis-2,3-epoxybutane, trans-2,3-epoxybutane, 9,9-(dimethoxymethyl)fluorene, isopentyl ether, and pentyl ether. In the present invention, one or more of the above-mentioned ether compounds having 3-5 carbon atoms, such as tetrahydrofuran and / or methyltetrahydrofuran, are preferred, and tetrahydrofuran is more preferred.

[0033] According to the present invention, the content of each component can be selected within a wide range. In a preferred embodiment of the present invention, based on the total weight of the catalyst components as 100% by weight, the content of the mesoporous material support is 20-90% by weight, preferably 20-70% by weight; the magnesium component is calculated as magnesium element, the titanium component is calculated as titanium element, the content of the magnesium component is 1-50% by weight, preferably 1-30% by weight, and the content of the titanium component is 1-50% by weight, preferably 1-30% by weight.

[0034] A second aspect of the present invention is to provide a method for preparing the catalyst component described in the first aspect, comprising:

[0035] In the presence of a protective atmosphere, the at least one mesoporous material carrier is subjected to a first contact reaction with the following raw materials: at least one magnesium compound, at least one alcohol ether compound and at least one ether compound, and then subjected to a second contact reaction with a titanium compound to obtain a slurry to be sprayed. The slurry to be sprayed is then spray-dried to obtain a catalyst component.

[0036] According to the present invention, the conditions for the first contact reaction can be selected within a wide range. In a preferred embodiment of the present invention, the conditions for the first contact reaction include: a temperature of 0-100°C and / or a time of 0.1-10h.

[0037] According to the present invention, the conditions for the second contact reaction can be selected within a wide range. In a preferred embodiment of the present invention, the conditions for the second contact reaction include: a temperature of 0-80°C and / or a reaction time of 0.5-10 h.

[0038] According to the present invention, the conditions for spray drying can be selected within a wide range. In a preferred embodiment of the present invention, the conditions for spray drying include: being carried out under a protective atmosphere, and / or having an inlet temperature of 100-200°C, and / or an outlet temperature of 60-130°C, and / or a carrier gas flow rate of 200-600 L / h.

[0039] In a preferred embodiment of the present invention, the preparation method includes:

[0040] (1) Magnesium compounds, alcohol ether compounds and ether compounds are reacted to form a magnesium compound solution;

[0041] (2) The solution obtained in step (1) is reacted with the mesoporous material carrier in the first contact reaction to obtain a slurry;

[0042] (3) The slurry obtained in step (2) is reacted with the titanium compound in a second contact reaction to obtain the masterbatch to be sprayed;

[0043] (4) The masterbatch to be sprayed obtained in step (3) is spray-dried to obtain the catalyst component.

[0044] According to the above technical solution, preferably, in step (1), the reaction temperature is 30-100℃, and more preferably 40-80℃.

[0045] According to the above technical solution, preferably, in step (2), the temperature of the first contact reaction is 0-100℃, more preferably 0-80℃; the reaction time is 0.5-10h, more preferably 0.5-4h; and / or,

[0046] According to the above technical solution, preferably, in step (3), the temperature of the second contact reaction is 0-80℃, more preferably 20-70℃; the reaction time is 0.5-10h, more preferably 0.5-5h; and / or,

[0047] According to the above technical solution, preferably, in step (4), the conditions for spray drying are: inlet temperature of 100-200℃, preferably 120-160℃; outlet temperature of 60-130℃, preferably 90-115℃.

[0048] According to the present invention, the amount of each raw material can be selected within a wide range. In a preferred embodiment of the present invention,

[0049] The amount of the mesoporous material carrier is 60-220 g, preferably 80-180 g, more preferably 90-160 g, relative to the amount of magnesium compound per mole of magnesium element; the amount of the titanium compound is 0.1-20 mol, preferably 0.1-5.0 mol, more preferably 0.1-3.0 mol, and most preferably 0.1-1.0 mol; and / or, the amount of the alcohol ether compound is 0.1-10 mol, preferably 0.1-5.0 mol, more preferably 0.1-3.0 mol, and most preferably 0.1-1.0 mol; and / or, the amount of the ether compound is 0.01-100 mol, preferably 5-80 mol, more preferably 15-60 mol, and most preferably 25-40 mol.

[0050] In a preferred embodiment of the present invention, the carrier is mixed with the mother liquor to form a slurry suitable for spray drying. This slurry maintains a more suitable viscosity, giving the sprayed particles better strength. Based on the total weight of the mesoporous material carrier, magnesium compound, titanium compound, alcohol ether compound, and ether compound (i.e., the total weight of the masterbatch to be sprayed), the content of the mesoporous material carrier is 3-50 wt%, preferably 3-30 wt%, more preferably 3-20 wt%; and / or, the weight percentage of the mesoporous material carrier in the catalyst component is 1-80 wt%, preferably 20-70 wt%, and the content of the titanium component is 1-50 wt%, preferably 1-15 wt%.

[0051] In the specific embodiments of the present invention described above, in step (1), the magnesium compound, the alcohol ether compound and the ether compound are brought into contact with each other and react at 30-100 °C, preferably at 40-80 °C. A relatively high temperature is beneficial to the reaction. The reaction is carried out under stirring conditions. The reaction time depends on the properties of the reactants and the operating conditions. The reaction time is required to be sufficient to obtain a transparent solution, and the required reaction time is 1-20 hours, preferably 2-10 hours, until a transparent solution is formed by the reaction; in step (2), the transparent solution obtained in step (1) is brought into contact with the mesoporous material support and reacts at 0-100 °C, preferably 0-80 °C; the mixing time is generally selected from 30 minutes to 10 hours, preferably 0.5-4 hours. The reaction in step (2) includes the reaction of the magnesium compound obtained in step (1) with the surface groups of the mesoporous material support, and the magnesium compound component enters the pores of the mesoporous material support by the capillary pressure of the pore structure of the support. Step (3) is to bring the suspension obtained in step (2) into contact with titanium halide and react. The reaction temperature is 0-80 °C, preferably 20-70 °C; the reaction time is 0.5-10 h, preferably 0.5-5 h, to obtain a mother liquor to be sprayed. In step (4), the spraying conditions include: the inlet temperature is 100-200 °C, preferably 120-160 °C; the outlet temperature is 60-130 °C, preferably 90-115 °C.

[0052] The protective atmosphere in the present invention is nitrogen and / or inert gas.

[0053] The third aspect of the present invention is to provide a catalyst, which is a reaction product containing the following components:

[0054] Component (A): the catalyst component described in the first aspect or the catalyst component obtained by the preparation method described in the second aspect;

[0055] Component (B): an organoaluminum compound with the general formula AlR p X 3-p , where R is a hydrocarbon group or hydrogen with 1-20 carbon atoms, X is a halogen atom, 1 < p ≤ 3, and p is an integer.

[0056] Among them, for component 2), one or more organoaluminum compounds can be selected and used in combination. The organoaluminum compound is preferably selected from at least one of AlEt3, Al(iso-Bu)3, Al(n-C6H 13 )3, Al(n-C,8H 17 )3, AlEt2Cl.

[0057] In the catalyst of this invention, the molar ratio of aluminum in the organoaluminum compound to titanium in the catalyst component is the aluminum-titanium ratio commonly used in catalysts in the art, preferably 20-500, more preferably 30-300. Components 1) and 2) can be used directly in the polymerization reaction, or they can be mixed and reacted first before being applied to the polymerization reaction.

[0058] A fourth aspect of the present invention is to provide a method for preparing the catalyst described in the third aspect, comprising the step of mixing and reacting the component (A) and the organoaluminum compound.

[0059] The conditions for mixing and reaction are conventional reaction conditions in the art and will not be described in detail here.

[0060] A fifth aspect of the present invention is the application of the catalyst component described in the first aspect, the catalyst component obtained by the preparation method described in the second aspect, the catalyst described in the third aspect, or the catalyst prepared by the preparation method described in the fourth aspect in an ethylene polymerization reaction; preferably,

[0061] Applications in homopolymerization of ethylene or copolymerization of ethylene with α-olefins.

[0062] The catalyst for ethylene polymerization described in this invention can be used in homopolymerization of ethylene and copolymerization of ethylene with other α-olefins. The polymerization conditions are not particularly limited and can be common olefin polymerization conditions in the art. The α-olefin can be at least one selected from propylene, butene, pentene, hexene, octene, and 4-methylpentene-1.

[0063] In their research on the preparation of polyolefins from olefin monomers, the inventors of this invention discovered that the mesoporous material support in the polyolefin catalyst prepared by the method of this invention, due to its special two-dimensional hexagonal channel structure, narrow pore size distribution, uniform channel distribution, and high specific surface area, can effectively improve the loading and dispersibility of the active components, thereby enhancing catalytic activity. As a result, the use of this polyolefin catalyst in olefin polymerization reactions can achieve a significantly improved conversion rate of reaction feedstocks, a higher bulk density of the obtained polymer, and further improvement in the molecular weight distribution of the obtained polyolefin product.

[0064] The beneficial effects of this invention are as follows:

[0065] The high specific surface area and pore structure of mesoporous materials effectively increase the loading of active centers, and they have high catalytic activity when used for homopolymerization or copolymerization of ethylene. When combined with specific raw materials in this invention, such as magnesium compound solution, titanium compound, alcohol ether compound and ether compound, the polymer powder prepared has a high packing density and a narrow molecular weight distribution. Attached Figure Description

[0066] Figure 1 This is a scanning electron microscope image of the catalyst obtained in Example 1.

[0067] Figure 2 This is a scanning electron microscope image of the catalyst obtained in Comparative Example 1. Detailed Implementation

[0068] The present invention will now be described in detail with reference to specific embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention are still within the scope of protection of the present invention.

[0069] The raw materials used in the specific embodiments of this invention are commercially available.

[0070] The present invention will be described in detail below through embodiments.

[0071] In the following examples and comparative examples, the triblock copolymer polyoxyethylene-polyoxypropylene-polyoxyethylene was purchased from Aldrich, abbreviated as P123, with the molecular formula EO. 20 PO 70 EO 20 The substance with the US Chemical Abstracts Registry number 9003-11-6 has an average molecular weight Mn of 5800.

[0072] Test method:

[0073] In the following examples and comparative examples, X-ray diffraction analysis was performed on a Bruker AXS D8 Advance X-ray diffractometer (Germany); catalyst morphology was determined using a FEI SL-30 field emission environmental scanning electron microscope (USA); pore structure parameters were analyzed using an ASAP2020-M+C adsorption analyzer (USA), and the specific surface area and pore volume of the samples were calculated using the BET method; particle size distribution was measured using a MASTERSIZE particle size analyzer with n-hexane as the dispersant, with a measurement range of 0.02-2000 μm; titanium content in the catalyst was determined using a Spectrumlab 752s UV-Vis spectrophotometer; magnesium content in the catalyst was determined using chemical titration; melt index of polyolefins was determined using the method specified in ASTM D1238-99; and bulk density was determined according to ASTM D1895-69.

[0074] Spray drying was carried out on a B-290 spray dryer manufactured by Buchi GmbH, Switzerland.

[0075] Example 1

[0076] This example illustrates a polyolefin catalyst and its preparation method.

[0077] 1. Preparation of the carrier

[0078] 4 g (0.0007 mol) of template agent P123 was added to a solution containing 37% by weight hydrochloric acid (16.4 mL) and water (128 mL), and stirred at 40 °C until P123 was completely dissolved. Then, 8.86 g (0.042 mol) of tetraethyl orthosilicate was added to the above solution, and stirred at 40 °C for 24 h. The resulting solution was then transferred to a polytetrafluoroethylene-lined reactor and crystallized at 150 °C for 24 h. After filtration and washing with deionized water four times, the solution was then filtered and dried to obtain mesoporous material powder. The mesoporous material powder was washed with ethanol under reflux for 24 h to remove the template agent, resulting in mesoporous molecular sieve A1. The product after template removal was then calcined at 400 °C for 10 h under nitrogen protection to remove the hydroxyl groups and residual water from the mesoporous material, resulting in thermally activated mesoporous material B1.

[0079] Under nitrogen protection, 10g of the thermally activated mesoporous material B1 and 3ml of dichlorodimethylsilane were placed in a 100ml ball mill jar. The ball mill jar was made of polytetrafluoroethylene, the grinding balls were made of agate, the diameter of the grinding balls was 3-15mm, the number of grinding balls was 30, the rotation speed was 400r / min, and the ball mill was carried out at 25℃ for 20h under nitrogen protection to obtain about 10g of mesoporous material carrier C1 with an average particle diameter of 1-10μm.

[0080] 2. Preparation of polyolefin catalysts

[0081] (1) Add 45 mmol of magnesium dichloride, 100 ml (1.24 mol) of tetrahydrofuran, and 9.8 mmol of ethylene glycol monobutyl ether to a glass reactor equipped with a stirrer that has been purged with N2 and kept under N2 atmosphere. Then heat the reactor to 70°C and stir until a transparent solution is formed.

[0082] (2) Cool the transparent solution obtained in step (1) to 25°C, add 6.0g of mesoporous material C1 to it, stir at 50°C for 1 hour to obtain a suspension;

[0083] (3) Add 9.8 mmol of titanium tetrachloride to the suspension obtained in step (2). After the addition is complete, stir the mixture at 70°C for 1 hour to obtain the slurry to be sprayed.

[0084] (4) Under N2 protection, spray drying was carried out in a BUCHI B-290 type closed-loop airflow spray dryer (inlet temperature is 140℃, outlet temperature is 105℃, carrier gas flow rate is 360L / h, and feed rate of the slurry to be sprayed is 7ml / min) to obtain solid free-flowing powdered polyolefin catalyst Cat-1.

[0085] The mesoporous material support C1 and the polyolefin catalyst Cat-1 were characterized using scanning electron microscopy and nitrogen adsorption.

[0086] In the catalyst Cat-1 obtained in this embodiment, the content of magnesium is 7.25% by weight and the content of titanium is 2.16% by weight.

[0087] X-ray diffraction pattern analysis was performed on mesoporous molecular sieve A1, with the horizontal axis representing 2θ and the vertical axis representing intensity. The XRD pattern clearly shows that mesoporous molecular sieve A1 exhibits diffraction peaks in the small-angle region, indicating that the mesoporous molecular sieve A1 possesses the two-dimensional ordered hexagonal channel structure unique to the mesoporous material SBA-15.

[0088] Figure 1 The image shows a scanning electron microscope (SEM) image of the microstructure of the polyolefin catalyst Cat-1. As can be seen from the image, the polyolefin catalyst Cat-1 has a spherical shape and a particle size in the micrometer range.

[0089] Table 1 shows the pore structure parameters of the mesoporous material support C1 and the polyolefin catalyst Cat-1.

[0090] Table 1

[0091] sample <![CDATA[Specific surface area (m 2 / g)]]> Pore ​​volume (mL / g) Average pore size (nm) Carrier C1 598 0.7 4.8 Catalyst Cat-1 582 0.6 4.5

[0092] As can be seen from the data in Table 1, the specific surface area and pore volume of the mesoporous material carrier C1 decreased after loading magnesium and titanium components, indicating that magnesium and titanium components entered the interior of the mesoporous material carrier C1 during the loading reaction.

[0093] Catalyst evaluation:

[0094] 1 L of hexane, 1 mmol of triethylaluminum, and 20 mg of the above catalyst components were added to a 2 L stainless steel stirred tank. The temperature was then raised to 75 °C, and hydrogen gas was added at 0.18 MPa. After hydrogenation, ethylene gas was added at 0.75 MPa, and the temperature was raised to 85 °C for polymerization. After 2 hours of reaction, the addition of ethylene was stopped, the temperature was lowered, the pressure was released, the polyethylene powder was weighed, and the catalyst activity was calculated. The bulk density of the polyethylene powder was tested, and the polymerization evaluation results are shown in Table 3.

[0095] Example 2

[0096] 1. Preparation of the carrier

[0097] 4 g (0.0007 mol) of template agent P123 was added to a solution containing 37% by weight hydrochloric acid (16.4 mL) and water (128 mL), and stirred at 40 °C until P123 was completely dissolved. Then, 10.9 g (0.0525 mol) of tetraethyl orthosilicate was added to the above solution, and stirred at 40 °C for 24 h. The resulting solution was then transferred to a polytetrafluoroethylene-lined reactor and crystallized at 180 °C for 20 h. After filtration and washing with deionized water four times, the solution was then filtered and dried to obtain mesoporous material powder. The mesoporous material powder was washed with ethanol under reflux for 24 h to remove the template agent, resulting in mesoporous molecular sieve material A2. The product after template removal was then calcined at 500 °C for 10 h under nitrogen protection to remove the hydroxyl groups and residual water, resulting in thermally activated mesoporous material B2.

[0098] Under nitrogen protection, 10g of the thermally activated mesoporous material B2 and 2ml of dichlorodimethylsilane were placed in a 100ml ball mill jar. The ball mill jar was made of polytetrafluoroethylene, and the grinding balls were made of agate with a diameter of 3-15mm, numbered 30, and rotated at 300r / min. Under nitrogen protection, the mixture was ball-milled at 30℃ for 20h to obtain approximately 10g of mesoporous material carrier C2 with an average particle diameter of 0.9-9μm.

[0099] 2. Preparation of polyolefin catalysts

[0100] The polyolefin catalyst was prepared according to the method of Example 1, and the catalyst was evaluated in the same way as in Example 1. The polymerization evaluation results are shown in Table 3.

[0101] The mesoporous material support C2 and the polyolefin catalyst Cat-2 were characterized using scanning electron microscopy and nitrogen adsorption.

[0102] In the catalyst Cat-2 obtained in this embodiment, the content of magnesium is 6.95% by weight and the content of titanium is 2.18% by weight.

[0103] Table 2 shows the pore structure parameters of the mesoporous material support C2 and the polyolefin catalyst Cat-2.

[0104] Table 2

[0105] sample <![CDATA[Specific surface area (m 2 / g)]]> Pore ​​volume (mL / g) Average pore size (nm) Carrier C2 583 0.9 5.3 Catalyst Cat-2 571 0.7 4.6

[0106] As can be seen from the data in Table 2, the specific surface area and pore volume of the mesoporous material carrier C2 decreased after loading magnesium and titanium components, indicating that magnesium and titanium components entered the interior of the mesoporous material carrier C2 during the loading reaction.

[0107] Example 3

[0108] The catalyst component was prepared according to the method of Example 1, except that the ethylene glycol monobutyl ether in catalyst preparation step (1) was replaced with 13.8 mmol instead of 9.8 mmol. The catalyst was evaluated as in Example 1, and the polymerization results are shown in Table 1.

[0109] The catalyst was evaluated in the same manner as in Example 1, and the polymerization results are shown in Table 3.

[0110] Example 4

[0111] The catalyst component was prepared according to the method of Example 1, except that 9.8 mmol of ethylene glycol monobutyl ether in catalyst preparation step (1) was replaced with 9.8 mmol of propylene glycol monomethyl ether.

[0112] The catalyst was evaluated in the same manner as in Example 1, and the polymerization results are shown in Table 3.

[0113] Example 5

[0114] The catalyst components were prepared according to the method of Example 1, except that 100 ml of tetrahydrofuran in catalyst preparation step (1) was replaced with 130 ml (1.60 mol) of tetrahydrofuran. The catalyst was evaluated as in Example 1, and the polymerization results are shown in Table 3.

[0115] Example 6

[0116] The catalyst component was prepared according to the method of Example 1, except that 9.8 mmol of ethylene glycol monobutyl ether in catalyst preparation step (1) was replaced with 15 mmol of propylene glycol monobutyl ether. The catalyst was evaluated as in Example 1, and the polymerization results are shown in Table 3.

[0117] Comparative Example 1

[0118] (1) Add 45 mmol magnesium dichloride, 120 ml tetrahydrofuran, and 9.8 mmol titanium tetrachloride sequentially to a glass reactor equipped with a stirrer and maintained by N2 purging. Heat the reactor to 70°C and stir until a transparent solution is formed.

[0119] (2) Cool the transparent solution obtained in step (1) to 50°C, add 6.0g of fumed hydrophobic silica (Cabot Corporation TS-610, particle size 0.02-0.1 micrometers) to it, stir and react for 1 hour to obtain a suspension;

[0120] (3) Under N2 protection, spray drying was carried out in a BUCHI B-290 type closed-loop airflow spray dryer (inlet temperature is 140℃, outlet temperature is 105℃, carrier gas flow rate is 360L / h, and feed rate of the slurry to be sprayed is 7ml / min) to obtain solid free-flowing powdered polyolefin catalyst.

[0121] The catalyst evaluation was the same as in Example 1. The polymerization reaction results are shown in Table 3, and the catalyst scanning electron microscopy test results are shown in Table 4. Figure 2 .

[0122] Comparative Example 2

[0123] (1) Add 45 mmol magnesium dichloride, 120 ml tetrahydrofuran, 9.8 mmol titanium tetrachloride, and 9.3 mmol epichlorohydrin sequentially to a glass reactor equipped with a stirrer and which has been purged with N2 and kept under N2 atmosphere. Heat the reactor to 70°C and stir until a transparent solution is formed.

[0124] (2) Cool the transparent solution obtained in step (1) to 50°C, add 6.0g of fumed hydrophobic silica (Cabot Corporation TS-610, particle size 0.02-0.1 micrometers) to it, stir and react for 1 hour to obtain a suspension;

[0125] (3) Under N2 protection, spray drying was carried out in a BUCHI B-290 type closed-loop airflow spray dryer (inlet temperature is 140℃, outlet temperature is 105℃, carrier gas flow rate is 360L / h, and feed rate of the slurry to be sprayed is 7ml / min) to obtain solid free-flowing powdered polyolefin catalyst.

[0126] The catalyst was evaluated in the same manner as in Example 1, and the polymerization results are shown in Table 3.

[0127] Comparative Example 3

[0128] The polyolefin catalyst was prepared according to the method of Example 1, except that 9.8 mmol of ethylene glycol monobutyl ether was not added in step 2 of the catalyst preparation. The catalyst was evaluated as in Example 1, and the polymerization results are shown in Table 3.

[0129] Table 3

[0130]

[0131]

[0132] (Where: BD—bulk density; melt flow ratio: MI21.6 / MI2.16)

[0133] As can be seen from the experimental data of the examples and comparative examples in Table 3, while maintaining a high level of catalyst activity, the polymer packing density is high, the polymer melt flow ratio is small, reflecting a narrow polymer molecular weight distribution. Figure 1 , Figure 2 As can be seen from the comparison, compared with the comparative catalyst, the catalyst of the present invention has a spherical particle shape, uniform particle size, good sphericity, and good dispersibility.

[0134] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

[0135] It should be noted that the embodiments described above are only for explaining the present invention and do not constitute any limitation on 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 explanatory terms, not limiting terms. Modifications can be made to the present invention within the scope of the claims, and revisions can be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described herein relates to specific methods, materials, and embodiments, it does not mean that the present invention is limited to the specific examples disclosed herein; on the contrary, the present invention can be extended to all other methods and applications with the same function.

[0136] All publications, patent applications, patents, and other references mentioned in this specification are incorporated herein by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings commonly understood by those skilled in the art. In case of conflict, the definitions in this specification shall prevail.

[0137] When this specification uses the prefixes “known to those skilled in the art,” “prior art,” or similar terms to derive materials, substances, methods, steps, apparatus, or components, the objects derived from such prefixes cover those commonly used in the art at the time of this application, but also include those that are not currently commonly used but will become generally recognized in the art as suitable for similar purposes.

[0138] The endpoints and any values ​​of the ranges disclosed in this application are not limited to the precise ranges or values; such ranges or values ​​should be understood to include values ​​close to them. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein. In principle, various technical solutions can be combined with each other to obtain new technical solutions, which should also be considered as specifically disclosed herein.

[0139] In the context of this specification, except where expressly stated otherwise, any matters or issues not mentioned shall apply directly to those known in the art without any modification.

[0140] Furthermore, any implementation described herein can be freely combined with one or more other implementations described herein, and the resulting technical solutions or technical ideas shall be regarded as part of the original disclosure or original record of the present invention, and should not be regarded as new content not disclosed or anticipated herein, unless those skilled in the art consider the combination to be obviously unreasonable.

Claims

1. A catalyst component, comprising the reaction product of the following components: At least one mesoporous material carrier, at least one magnesium compound, at least one titanium compound, at least one alcohol ether compound, and at least one ether compound; in, The mesoporous material carrier has a two-dimensional hexagonal pore structure, an average pore size of 4-15 nm, a specific surface area of 550-650 m 2 / g, a pore volume of 0.5-1.5 mL / g, and an average particle size of 0.5-10 μm. The mesoporous material carrier is prepared by the following method: (a) In the presence of a template agent, a silicon source and an acid agent are mixed and contacted, and the mixture obtained after mixing and contact is crystallized, filtered and dried in sequence to obtain mesoporous material powder; (b) The mesoporous material powder is subjected to template release agent treatment, thermal activation treatment and ball milling treatment in sequence to obtain a mesoporous material carrier, and dichlorodimethylsilane is added during the ball milling process; The alcohol ether compound is selected from one or more of propylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monomethyl ether, ethylene glycol monopropyl ether, propylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monobutyl ether, and propylene glycol monopropyl ether. The ether compound is selected from one or more of 1,4-dioxane, tetrahydrofuran, and methyltetrahydrofuran.

2. The catalyst component according to claim 1, characterized in that: In step (a), the conditions for the mixing contact include: a temperature of 25-60°C and a time of 25 minutes or more; and / or, The template agent is a triblock copolymer of polyethylene oxide-polypropylene oxide-polyethylene oxide; and / or... The acid is at least one selected from hydrochloric acid, sulfuric acid, nitric acid, and hydrobromic acid; and / or, The silicon source is at least one selected from tetraethyl orthosilicate, methyl orthosilicate, propyl orthosilicate, sodium orthosilicate, and silica sol; and / or, The molar ratio of the template agent to the silicon source is 1:(10-90); and / or, The crystallization conditions include a temperature of 90-180℃ and a time of 10-40h.

3. The catalyst component according to claim 1, characterized in that: In step (b), the template release agent treatment process includes: washing the mesoporous material powder with alcohol; and / or, The conditions for the thermal activation treatment include: a thermal activation temperature of 300-900℃, and / or a thermal activation time of 7-10 hours; and / or, The conditions for ball milling include: the rotation speed of the grinding balls is 300-500 r / min, and / or the temperature inside the ball mill jar is 15-100℃, and / or the ball milling time is 0.1-100 h.

4. The catalyst component according to claim 1, characterized in that: In step (b), the template release agent treatment process includes: washing the mesoporous material powder with alcohol at 90-120°C for 10-40 hours.

5. The catalyst component according to claim 1, characterized in that: The magnesium compound is selected from the formula Mg(OR1). m Cl 2-m One or more of the compounds shown, wherein R1 is C2-C 20 hydrocarbon group or C3-C 20 Cyclic hydrocarbon groups, 0 ≤ m ≤ 2; and / or, The titanium compound is selected from one or more titanium halides.

6. The catalyst component according to claim 5, characterized in that: The magnesium compound is selected from the formula Mg(OR1). m Cl 2-m One or more of the compounds shown, wherein R1 is C2-C 10 Alkyl groups, 0 ≤ m ≤ 2; and / or, The titanium compound is selected from one or more of titanium chloride and titanium bromide.

7. The catalyst component according to claim 5, characterized in that: The magnesium compound is selected from at least one of magnesium diethoxy, magnesium diepropoxy, magnesium diebutoxy, magnesium dioctyloxy, and magnesium dichloride; and / or, The titanium compound is selected from one or two of titanium trichloride and titanium tetrachloride.

8. The catalyst component according to any one of claims 1-7, characterized in that: Based on the total weight of the catalyst components as 100% by weight, the content of the mesoporous material support is 20-90% by weight; the magnesium component is calculated as magnesium element, and the titanium component is calculated as titanium element, with the content of the magnesium component being 1-50% by weight and the content of the titanium component being 1-50% by weight.

9. The catalyst component according to any one of claims 1-7, characterized in that: Based on the total weight of the catalyst components as 100% by weight, the content of the mesoporous material support is 20-70% by weight; the magnesium component is calculated as magnesium element, and the titanium component is calculated as titanium element, with the content of the magnesium component being 1-30% by weight and the content of the titanium component being 1-30% by weight.

10. A method for preparing a catalyst component according to any one of claims 1-9, comprising: In the presence of a protective atmosphere, the at least one mesoporous material carrier is subjected to a first contact reaction with the following raw materials: at least one magnesium compound, at least one alcohol ether compound and at least one ether compound, and then subjected to a second contact reaction with a titanium compound to obtain a slurry to be sprayed. The slurry to be sprayed is then spray-dried to obtain a catalyst component.

11. The preparation method according to claim 10, characterized in that: The conditions for the first contact reaction include: The temperature is 0-100℃, and / or the time is 0.1-10h; and / or, The conditions for the second contact reaction include: The temperature is 0-80℃, and / or the reaction time is 0.5-10h; and / or, The conditions for spray drying include: being carried out under a protective atmosphere, and / or having an inlet temperature of 100-200°C, and / or an outlet temperature of 60-130°C, and / or a carrier gas flow rate of 200-600 L / h.

12. The preparation method according to claim 10, characterized in that, The preparation method includes: (1) Magnesium compounds, alcohol ether compounds and ether compounds are reacted to form a magnesium compound solution; (2) The solution obtained in step (1) is reacted with the mesoporous material carrier in the first contact reaction to obtain a slurry; (3) The slurry obtained in step (2) is reacted with the titanium compound in a second contact reaction to obtain the masterbatch to be sprayed; (4) The masterbatch to be sprayed obtained in step (3) is spray-dried to obtain the catalyst component.

13. The preparation method according to claim 12, characterized in that, In step (1), the reaction temperature is 30-100℃; and / or, In step (2), the temperature of the first contact reaction is 0-100℃; the first contact reaction time is 0.5-10h; and / or, In step (3), the temperature of the second contact reaction is 0-80℃; the reaction time is 0.5-10h; and / or, In step (4), the spray drying conditions are: inlet temperature of 100-200℃; outlet temperature of 60-130℃.

14. The preparation method according to claim 12, characterized in that, In step (1), the reaction temperature is 40-80℃; and / or, In step (2), the temperature of the first contact reaction is 0 - 80°C; the first contact reaction time is 0.5 - 4 h; and / or, In step (3), the temperature of the second contact reaction is 20 - 70°C; the second contact reaction time is 0.5 - 5 h; and / or, In step (4), the conditions for spray drying are: the inlet temperature is 120 - 160°C; the outlet temperature is 90 - 115°C.

15. The preparation method according to any one of claims 10 - 14, wherein: Relative to each mole of the magnesium compound calculated as magnesium element, the dosage of the mesoporous material support is 60 - 220 g; the dosage of the titanium compound is 0.1 - 20 moles; and / or, the dosage of the alcohol ether compound is 0.1 - 10 moles; and / or, the dosage of the ether compound is 0.01 - 100 moles.

16. The preparation method according to any one of claims 10 - 14, wherein: Relative to each mole of the magnesium compound calculated as magnesium element, the dosage of the mesoporous material support is 80 - 180 g; the dosage of the titanium compound is 0.1 - 5.0 moles; and / or, the dosage of the alcohol ether compound is 0.1 - 5.0 moles; and / or, the dosage of the ether compound is 5 - 80 moles.

17. The preparation method according to any one of claims 10 - 14, wherein: Relative to each mole of the magnesium compound calculated as magnesium element, the dosage of the mesoporous material support is 90 - 160 g; the dosage of the titanium compound is 0.1 - 3.0 moles; and / or, the dosage of the alcohol ether compound is 0.1 - 3.0 moles; and / or, the dosage of the ether compound is 15 - 60 moles.

18. A catalyst comprising the reaction product of the following components: Component (A): The catalyst component according to any one of claims 1 - 9 or the catalyst component obtained by the preparation method according to any one of claims 10 - 17; Component (B): General formula AlR p X 3-p Organoaluminum compounds, among which, R is a hydrocarbon group having 1 - 20 carbon atoms or hydrogen, X is a halogen atom, 1 < p ≤ 3, and p is an integer.

19. A preparation method of the catalyst according to claim 18, comprising the step of mixing and reacting the component (A) and the organoaluminum compound.

20. Use of the catalyst component according to any one of claims 1 - 9 or the catalyst component obtained by the preparation method according to any one of claims 10 - 17 or the catalyst according to claim 18 or the catalyst prepared by the preparation method according to claim 19 in the ethylene polymerization reaction.

21. The use according to claim 20, wherein: The use is in the application of ethylene homopolymerization or copolymerization of ethylene with an α-olefin.

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