Alkoxymagnesium particles, solid catalyst components, catalysts and olefin polymerization processes

Abstract

The present application discloses a kind of alkoxy magnesium particles and preparation method, solid catalyst component, catalyst, and a kind of olefin polymerization method.The particle size of the alkoxy magnesium particles is 1-100 μm, total pore volume is 0.1-4 cm 3 / g, specific surface area is 20-110 m 2 / g.The structure of the alkoxy magnesium particles can be adjusted, and when the prepared solid catalyst component is used for ethylene polymerization or copolymerization, the polymer obtained by polymerization has high bulk density, low fine powder content, and high catalyst activity.

Description

Technical Field

[0001] This invention relates to the field of catalysts, and more specifically, to alkoxymagnesium particles for homopolymerization and copolymerization of olefins and their preparation method, solid catalyst components, catalysts, and an olefin polymerization method. Background Technology

[0002] China has become the world's largest producer and consumer of polyolefins, with a production volume of approximately 64 million tons in 2023, and this figure is growing rapidly every year. Currently, over 90% of polyolefin plants worldwide use zinc catalysts for production. Alkoxymagnesium catalysts, as a typical representative of zinc catalysts, possess advantages such as good particle morphology and excellent hydrogen regulation performance.

[0003] Alkoxymagnesium catalysts are Zn catalysts prepared using alkoxymagnesium as a support. These catalysts are prepared by reacting alkoxymagnesium with titanium-containing compounds in the presence of an electron donor. The particle morphology of the catalyst and the support exhibits significant reproducibility. Therefore, the particle morphology of the support determines the particle morphology of the catalyst, which in turn determines the particle morphology and packing density of the polymer.

[0004] To date, numerous institutions both domestically and internationally have conducted research on alkoxymagnesium supports and catalysts, including companies such as Soda, Idemitsu, Basel, Degussa, and Sinopec. With continuous technological advancements and catalyst iterations, catalyst research has primarily focused on areas such as low fineness, high bulk density, high copolymerization performance, high hydrogen regulation performance, and high activity. Among these, high activity, low fineness, and high bulk density have consistently been the goals pursued by researchers developing alkoxymagnesium catalysts.

[0005] However, the high activity of the catalyst can lead to strong breakage during the catalyst polymerization process, making it difficult to simultaneously achieve high catalyst activity, high polymer packing density, and low fine powder content.

[0006] Therefore, preparing a catalyst with high activity, excellent anti-breakage performance, high bulk density, and low fine powder content is a technical problem that urgently needs to be solved. Summary of the Invention

[0007] To address the problems in existing technologies, this invention proposes alkoxymagnesium particles for olefin homopolymerization and copolymerization, a preparation method thereof, solid catalyst components, a catalyst, and an olefin polymerization method. During the research process, this invention unexpectedly discovered that when the total pore volume of the alkoxymagnesium particles is 0.5–4 cm³… 3 / g, specific surface area less than 150m² 2 When this alkoxymagnesium support is used to prepare catalysts for olefin homopolymerization and copolymerization, the resulting catalysts have high activity, low fine powder content, and high bulk density after polymerization.

[0008] One of the objectives of this invention is to provide alkoxymagnesium particles.

[0009] The total pore volume of the alkoxymagnesium particles is 0.1–4 cm³. 3 / g, for example, can be 0.1cm 3 / g, 0.5cm 3 / g, 1cm 3 / g、2cm 3 / g, 3cm 3 / g、4cm 3 / g, etc.; specific surface area is 20-110m² 2 / g, for example, can be 20m 2 / g、30m 2 / g、40m 2 / g, 50m 2 / g、60m 2 / g、70m 2 / g、80m 2 / g、90m 2 / g, 100m 2 / g、110m 2 / g, etc. Preferably, the total pore volume is 0.5–4 cm³. 3 / g, specific surface area of ​​30-100m² 2 / g.

[0010] In the alkoxymagnesium particles, the volume of pores with a diameter of less than 1 μm has a volume ratio of more than 50 nm, preferably 60% to 99%, for example, 55%, 60%, 70%, 80%, 90%, 99%, etc.

[0011] The particle size of the alkoxymagnesium particles is 1–100 μm, preferably 3–60 μm.

[0012] The alkoxymagnesium particles comprise the reaction product of the following components: magnesium powder, halogenating agent, mixed alcohol, organosiloxane compound and / or organic epoxy compound.

[0013] The average particle size of the magnesium powder is below 300 μm, and it can be of any shape, provided that its reactivity is good.

[0014] The halogenating agent can be at least one of elemental halogen, inorganic halide, and organic halide, preferably at least one of elemental iodine, elemental bromine, chlorine, magnesium iodide, magnesium chloride, magnesium bromide, calcium bromide, calcium chloride, calcium iodide, manganese chloride, and alkoxy magnesium halide. The halogenating agent can be added all at once at the beginning of the reaction or added in stages.

[0015] The mixed alcohol is a mixture of alcohols or a mixture of alcohols and phenols, wherein the alcohol is at least one of a straight-chain or branched monohydric alcohol or a polyhydric alcohol, preferably C1 to C2. 10 Alcohols, more preferably methanol, ethanol, n-propanol, isopropanol, n-butanol, n-pentanol, 1-hexanol, 1-octanol, 1-heptanol, 2-ethylhexanol, 2-pentanol, 2-butanol, 2-hexanol, 2-heptanol, 2-octanol, 4-methyl-2-pentanol, 2-phenylethanol, ethylene glycol, glycerol, and 1-phenyl-1-propanol; the phenols are unsubstituted or alkyl-substituted phenols, preferably phenols or C1-C1 phenols. 10 Alkyl-substituted phenols.

[0016] For example, the mixed alcohol can be at least two of methanol, ethanol, n-propanol, isopropanol, n-butanol, n-pentanol, 1-hexanol, 1-octanol, 1-heptanol, 2-ethylhexanol, 2-pentanol, 2-butanol, 2-hexanol, 2-heptanol, 2-octanol, 4-methyl-2-pentanol, 2-phenylethanol, ethylene glycol, glycerol, and 1-phenyl-1-propanol. It can also be a mixture of the above-mentioned alcohols with phenol or alkyl-substituted phenols, more preferably a mixture of ethanol with other alcohols or phenols, wherein the ethanol content is greater than 80%. The mixed alcohol can be added all at once during the reaction or added in portions; the mixed alcohol can be added together or separately.

[0017] The organosiloxane compounds are preferably methyltriethoxysilane, dimethyldiethoxysilane, trimethylethoxysilane, triethoxysilane, tetraethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, trimethoxysilane, tetramethoxysilane, methyltripropoxysilane, dimethyldipropoxysilane, trimethylpropoxysilane, tripropoxysilane, tetrapropoxysilane, methyltriisopropoxysilane, dimethyldiisopropoxysilane, trimethylisopropoxysilane, triisopropoxysilane, tetraisopropoxysilane, vinyltriisopropoxysilane, propyltriethoxysilane, n,n-dimethyl-3 -At least one of aminopropyltrimethoxysilane, propyltriethoxysilane, ethyltriethoxysilane, diethyldiethoxysilane, triethylethoxysilane, ethyltrimethoxysilane, diethyldimethoxysilane, triethylmethoxysilane, ethyltripropoxysilane, diethyldipropoxysilane, triethylpropoxysilane, diethyldiisopropoxysilane, triethylisopropoxysilane, diallyldiethoxysilane, diisopropyldiethoxysilane, diisopropyldimethoxysilane, diallyldimethoxysilane, and dimethyldi(allyloxy)silane. Organosiloxane compounds may be added all at once or in portions during the reaction.

[0018] The organic epoxy compound is selected from at least one of propylene oxide, ethylene oxide, butane oxide, butadiene oxide, butadiene dioxide, epichlorohydrin, methyl glycidyl ether, and diglycidyl ether.

[0019] The amount of the halogenating agent per mole of magnesium is 0.0001 to 0.05 mol, for example, 0.0001 mol, 0.001 mol, 0.005 mol, 0.01 mol, 0.02 mol, 0.03 mol, 0.04 mol, 0.05 mol, etc.; the amount of the mixed alcohol is 1 to 30 mol, for example, 1 mol, 3 mol, 5 mol, 7 mol, 10 mol, 12 mol, 15 mol, 20 mol, 25 mol, 30 mol, etc.; the amount of the organosiloxane compound or the organic epoxy compound is 0 to 1 mol each, for example, 0.001 mol, 0.005 mol, 0.01 mol, 0.05 mol, 0.1 mol, 0.2 mol, 0.3 mol, 0.4 mol, 0.5 mol, 0.6 mol, 0.7 mol, 0.8 mol, 0.9 mol, 1 mol, etc., but not all of them are 0.

[0020] Preferably, the amount of the halogenating agent is 0.0001 to 0.02 mol per mole of magnesium; the amount of the mixed alcohol is 3 to 15 mol; and the amount of the organosiloxane compound or the organic epoxy compound is 0 to 0.5 mol each, but not both simultaneously 0.

[0021] According to embodiments of the present invention, the introduction of organosiloxane compounds and / or organic epoxy compounds can effectively regulate the reaction rate and product precipitation balance, thereby effectively controlling the support structure and achieving precise control of support particle size, lamellar size, and pore structure.

[0022] A second objective of this invention is to provide a method for preparing alkoxy magnesium particles, comprising reacting magnesium powder, a halogenating agent, a mixed alcohol, an organosiloxane compound and / or an organic epoxy compound under an inert atmosphere, preferably at a temperature below 80°C.

[0023] The inert atmosphere is a protective gas that does not participate in the reaction, preferably an inert gas or nitrogen, and more preferably argon or nitrogen.

[0024] The amount of the halogenating agent per mole of magnesium is 0.0001 to 0.05 moles; the amount of the mixed alcohol is 1 to 30 moles; and the amount of the organosiloxane compound or the organic epoxy compound is 0 to 1 mole each, but not both simultaneously 0.

[0025] In the preparation of the alkoxymagnesium particles provided by this invention, the order in which the reaction raw materials are added can be set as needed, without any particular limitation.

[0026] In the preparation of the alkoxymagnesium particles provided by this invention, they can be added to the reaction system individually or in solution form. All raw materials can be added at once or in stages depending on the actual situation.

[0027] In the preparation of the alkoxymagnesium particles provided by this invention, the reaction temperature can be between 0 and 80°C, and the preparation temperature of the carrier can be selected according to requirements. The preferred isothermal temperature is 40°C to reflux temperature.

[0028] In the preparation of the alkoxymagnesium particles provided by this invention, the reaction time needs to be longer than the complete reaction time of magnesium powder, usually 2 to 10 hours, and the degree of reaction is judged according to the amount of hydrogen emitted.

[0029] In the preparation of alkoxymagnesium particles of the present invention, the form, type and stirring rate of the stirring paddle are not limited, and the form, type and stirring rate of the stirring paddle are adjusted according to the needs of the product.

[0030] In the preparation of the alkoxymagnesium particles provided by the present invention, the reaction product can be stored in the form of dry powder or in an organic solvent selected from at least one of toluene, hexane, ethanol, benzene, heptane, octane, decane, xylene, white oil, paraffin or silicone oil.

[0031] In the preparation of the alkoxymagnesium particles provided by the present invention, the alkoxymagnesium particles can be directly dried, or they can be washed with an organic solvent selected from at least one of toluene, hexane, ethanol, benzene, heptane, octane, decane, xylene, white oil, paraffin or silicone oil. The number of washing times is not limited as needed.

[0032] A third objective of this invention is to provide a solid catalyst component for olefin polymerization or copolymerization, wherein the solid catalyst component comprises the reaction products of the following components:

[0033] 1) The alkoxy magnesium particles described in one of the objectives of this invention;

[0034] 2) Titanium-containing compounds;

[0035] The general formula of the titanium-containing compound is Ti(OR1). y X 4-y In the formula, R1 represents C1 to C2. 10 The hydrocarbon group, where X is a halogen atom, 0≤y≤3; preferably, R1 is selected from C1~C6 alkyl, C2~C6 alkenyl, C3 ... 10 cycloalkyl or C6-C 10The aromatic hydrocarbon group, more preferably, R1 is selected from methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, cyclopropyl, methylcyclopropyl, n-pentyl, methylcyclopentyl, cyclohexyl, phenyl, benzyl or xylyl; even more preferably, the titanium-containing compound is selected from at least one of TiCl4, Ti(OC2H5)Cl3, Ti(OCH3)Cl3 or Ti(OC4H9)Cl3, and the titanium-containing compound can be added all at once during the reaction or added in portions.

[0036] Option 3) an internal electron-donating compound; said internal electron-donating compound is selected from at least one of monocarboxylic acid esters and / or siloxanes.

[0037] The monocarboxylic acid ester compound is preferably selected from at least one of methyl formate, ethyl formate, propyl formate, butyl formate, pentyl formate, hexyl formate, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, pentyl acetate, hexyl acetate, methyl propionate, ethyl propionate, propyl propionate, butyl propionate, pentyl propionate, hexyl propionate, methyl butyrate, ethyl butyrate, propyl butyrate, butyl butyrate, pentyl butyrate, hexyl butyrate, methyl valerate, ethyl valerate, propyl valerate, butyl valerate, pentyl valerate, hexyl valerate, methyl hexanoate, ethyl hexanoate, propyl hexanoate, butyl hexanoate, pentyl hexanoate, hexyl hexanoate, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, pentyl benzoate, and hexyl benzoate. The internal electron donor compound can be added all at once during the reaction or added in portions.

[0038] The siloxane compounds are selected from tetramethyltriethoxysilane, dimethyldiethoxysilane, trimethylethoxysilane, triethoxysilane, tetraethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, trimethoxysilane, tetramethoxysilane, methyltripropoxysilane, dimethyldipropoxysilane, trimethylpropoxysilane, tripropoxysilane, tetrapropoxysilane, methyltriisopropoxysilane, dimethyldiisopropoxysilane, trimethylisopropoxysilane, triisopropoxysilane, tetraisopropoxysilane, vinyltriisopropoxysilane, propyltriethoxysilane isocyanate, and n,n-dimethyl-3-aminopropane. Trimethoxysilane, propyltriethoxysilane, ethyltriethoxysilane, diethyldiethoxysilane, triethylethoxysilane, ethyltrimethoxysilane, diethyldimethoxysilane, triethylmethoxysilane, ethyltripropoxysilane, diethyldipropoxysilane, triethylpropoxysilane, diethyldiisopropoxysilane, triethylisopropoxysilane, diallyldiethoxysilane, diisopropyldiethoxysilane, diisopropyldimethoxysilane, diallyldimethoxysilane, dimethyldi(allyloxy)silane, tetra(2-ethylhexyloxy)silane, n-propyltriethoxysilane, n-propyltrimethoxysilane, decyltrimethoxysilane, Decyltriethoxysilane, cyclopentyltrimethoxysilane, cyclopentyltriethoxysilane, 2-methylcyclopentyltrimethoxysilane, 2,3-dimethylcyclopentyltrimethoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, tert-butyltriethoxysilane, n-butyltrimethoxysilane, n-butyltriethoxysilane, isobutyltrimethoxysilane, isobutyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, monochlorotrimethoxysilane, monochlorotriethoxysilane, vinyltributoxysilane, trimethylphenoxysilane, methyltrienepropoxysilane, tert-butylmethyldimethoxysilane, tert-butylmethyldiethoxysilane, tert-butyltrimeth ... At least one of the following: pentylmethyldiethoxysilane, dicyclopentyldimethoxysilane, dicyclopentyldiethoxysilane, methylcyclopentyldiethoxysilane, methylcyclopentyldimethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane, di-o-tolyldimethoxysilane, di-o-tolyldiethoxysilane, di-m-tolyldimethoxysilane, di-m-tolyldiethoxysilane, di-p-tolyldimethoxysilane, di-p-tolyldiethoxysilane, tricyclopentylmethoxysilane, tricyclopentylethoxysilane, dicyclopentylmethylmethoxysilane, and cyclopentyldimethylmethoxysilane.

[0039] The amount of the titanium-containing compound used per mole of magnesium is 1 to 50 mol, preferably 1 to 20 mol, for example, 1 mol, 5 mol, 10 mol, 20 mol, 30 mol, 40 mol, 50 mol, etc.; the amount of the internal electron-donating compound used is 0 to 2 mol, preferably 0 to 1 mol, for example, 0.01 mol, 0.05 mol, 0.1 mol, 0.2 mol, 0.5 mol, 1 mol, 1.5 mol, 2 mol, etc.

[0040] The fourth objective of this invention is to provide a catalyst for olefin polymerization.

[0041] The catalyst comprises the following components:

[0042] Component I: The solid catalyst component described in the third objective of this invention;

[0043] Component II: Organoaluminum compounds;

[0044] The general formula of the organoaluminum compound is AlR d X 3-d In which the repeated R is independently hydrogen or C1~C 20 Hydrocarbon group, X is a halogen atom, 0 < d ≤ 3.

[0045] In the organoaluminum compound, the repeated R is independently hydrogen or C1-C2. 10 The hydrocarbon group; preferably, R is hydrogen or a C1-C5 hydrocarbon group; more preferably, the organoaluminum compound is selected from at least one of Al(CH3)3, Al(CH2CH3)3, Al(i-Bu)3, AlH(CH2CH3)2, AlH(i-Bu)2, AlCl(CH2CH3)2, Al2Cl3(CH2CH3)3, and AlCl2(CH2CH3).

[0046] In the catalyst, the molar ratio of aluminum in component II to titanium in component I is 10:1 to 200:1, preferably 20:1 to 100:1, for example, it can be 10:1, 20:1, 50:1, 80:1, 100:1, 120:1, 150:1, 180:1, 200:1, etc.

[0047] The fifth objective of this invention is to provide an olefin polymerization method, comprising: contacting one or more olefins with the catalyst described in the fourth objective of this invention under olefin polymerization reaction conditions.

[0048] The polymerization can be olefin polymerization or α-olefin copolymerization.

[0049] The olefin is preferably one or a mixture of ethylene, butene, and hexene.

[0050] This invention provides alkoxymagnesium particles for olefin polymerization or copolymerization, a method for their preparation, a solid catalyst component, a catalyst system, and a method for olefin polymerization. The structure of the alkoxymagnesium particles is tunable, and when the prepared solid catalyst component is used for ethylene polymerization or copolymerization, the polymer produced has high bulk density, low fine powder content, and high catalyst activity. Detailed Implementation

[0051] 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.

[0052] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. 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.

[0053] Unless otherwise specified, the raw materials used in the examples and comparative examples are all disclosed in the prior art, such as those that can be directly purchased or prepared according to the preparation methods disclosed in the prior art.

[0054] In the following examples and comparative examples:

[0055] 1. Particle size and particle size distribution of alkoxymagnesium support and catalyst: A Malvern Mastersizer laser particle size analyzer was used. Where Span = (D90 - D10) / D50.

[0056] 2. The pore volume and specific surface area were determined by mercury indentation method.

[0057] 3. Bulk density of polymer: determined by the method of weight of loose solids per unit volume (GB / T1636).

[0058] 4. The content of polymer fine powder is determined by sieving 100g of powder through a 200-mesh (75μm) sieve. The amount of polymer passing through the sieve is recorded as W, and the content of fine powder is W.

[0059] 5. Aggregate evaluation:

[0060] A 2L stainless steel reactor was fully purged with high-purity nitrogen, then 1L of hexane and 2.0mL of 1M triethylaluminum solution were added, followed by the solid catalyst (containing 0.6mg titanium) prepared in the examples and comparative examples. The temperature was raised to 70°C, and hydrogen was introduced to bring the pressure inside the reactor to 0.28MPa. Ethylene was then introduced to bring the total pressure inside the reactor to 0.73MPa, and polymerization was carried out at 80°C for 2 hours.

[0061] All pressures mentioned above refer to absolute pressures within the vessel.

[0062] The present invention will be further described below with reference to specific embodiments.

[0063] Example 1

[0064] In a reactor equipped with a stirrer, a reflux condenser is installed, with a conduit inserted above the reflux condenser. The other end of the conduit is connected to an oil seal device for easy observation of H2 generation.

[0065] 1) Preparation of alkoxymagnesium support

[0066] The reactor was fully purged with high-purity nitrogen. Under nitrogen protection, 0.3 g (1.1 mmol) of iodine, 120 mL of mixed alcohol (96% wt ethanol, 4% isooctanol), and 4 mL (0.027 mol) of tetramethoxysilane were added and stirred for 30 min. Then, 6 g (0.25 mol) of magnesium powder (average particle size 80 μm) was added, and the temperature was slowly raised to 65 °C for reaction. After 30 min, 60 mL of ethanol and 1 mL (0.0127 mol) of epichlorohydrin were added, and the mixture was kept at a constant temperature for 4 h. The mixture was then washed four times with anhydrous ethanol and hexane, separated, and dried to obtain a white solid powder with good flowability.

[0067] 2) Preparation of alkoxymagnesium catalyst

[0068] In a 300 mL stirred 5-necked reactor fully purged with nitrogen, 4 g of the prepared support and 40 mL of toluene were added. The mixture was cooled to -15 °C, and 2 mL of ethyl acetate was added. 24 mL of TiCl4 was slowly added dropwise with stirring over a period of 1 h. 1 mL of TEOS was then added, and the mixture was heated to 80 °C and held at that temperature for 2 h. After settling, the supernatant was decanted and washed twice with 100 mL of hexane at 60 °C. After decanting, 3 mL of 1 M triethylaluminum solution was added, and the mixture was stirred for 4 h. After settling, the supernatant was decanted and washed four times with 100 mL of hexane at 50 °C. After drying, a solid catalyst with good flowability was obtained.

[0069] Example 2

[0070] The method is the same as in Example 1, except that the organosiloxane compounds added during the preparation of the carrier are 4 mL (0.019 mol) of dimethyl diisopropoxysilane and 0.5 mL (0.0064 mol) of epichlorohydrin.

[0071] Example 3

[0072] The method is the same as in Example 1, except that the organosiloxane compound added during the preparation of the carrier is 1 mL (0.007 mol) of tetramethoxysilane.

[0073] Example 4

[0074] The method is the same as in Example 1, except that the organosiloxane compounds added during the preparation of the carrier are 1 mL (0.005 mol) of dimethyl diisopropoxysilane and 2 mL (0.009 mol) of tetraethoxysilane.

[0075] Example 5

[0076] The method is the same as in Example 1, except that no organosiloxane compounds are added during the preparation of the carrier.

[0077] Example 6

[0078] The method is the same as in Example 1, except that no epoxide compound is added during the preparation of the carrier.

[0079] Example 7

[0080] The method is the same as in Example 1, except that no monocarboxylic acid ester electronic compound is added during the catalyst preparation process.

[0081] Example 8

[0082] The method is the same as in Example 1, except that no siloxane compounds are added during the catalyst preparation process.

[0083] Example 9

[0084] The method is the same as in Example 1, except that the electron donor added during catalyst preparation is 2.5 mL of ethyl benzoate.

[0085] Comparative Example 1

[0086] 1) Preparation of alkoxymagnesium support

[0087] The reactor was fully purged with high-purity nitrogen. Under nitrogen protection, 0.3 g (1.1 mmol) of iodine and 120 mL of mixed alcohol (96% wt ethanol and 4% isooctanol) were added and stirred for 30 min. Then, 6 g (0.25 mol) of magnesium powder (average particle size 80 μm) was added and the temperature was slowly raised to 65 °C for reaction. After 30 min, 60 mL of ethanol was added and the temperature was kept constant for 4 h. The mixture was then washed four times with anhydrous ethanol and hexane, separated, and dried to obtain a white solid powder with good flowability.

[0088] 2) Preparation of alkoxymagnesium catalyst

[0089] In a 300 mL stirred 5-necked reactor that had been fully purged with nitrogen, 4 g of the prepared support and 40 mL of toluene were added. The mixture was cooled to -15 °C, and 24 mL of TiCl4 was slowly added dropwise with stirring over a period of 1 h. The temperature was then raised to 80 °C and held at that temperature for 2 h. After settling, the supernatant was decanted and washed four times with 100 mL of hexane at 60 °C. After drying, a solid catalyst with good flowability was obtained.

[0090] Comparative Example 2

[0091] The method was the same as that used in Comparative Example 1, except that 2 mL of ethyl acetate was added during the catalyst preparation process.

[0092] Comparative Example 3

[0093] The method is the same as that used in Comparative Example 1, except that 1 mL of TEOS is added during the catalyst preparation process.

[0094] Comparative Example 4

[0095] The reactor was fully purged with high-purity nitrogen. Under nitrogen protection, 0.3 g (1.1 mmol) of iodine, 80 mL of ethanol, and 4 mL (0.027 mol) of tetramethoxysilane were added and stirred for 30 min. Then, 6 g (0.25 mol) of magnesium powder (average particle size 80 μm) was added, and the temperature was slowly raised to 65 °C for reaction. After 30 min, 60 mL of ethanol was added, and the temperature was kept constant for 4 h. The mixture was then washed four times with anhydrous ethanol and hexane, separated, and dried to obtain a white solid powder with good flowability.

[0096] In a 300 mL stirred 5-necked reactor fully purged with nitrogen, 4 g of the prepared support and 40 mL of toluene were added. The mixture was cooled to -15 °C, and 2 mL of ethyl acetate was added. 24 mL of TiCl4 was slowly added dropwise with stirring over a period of 1 h. The temperature was then raised to 80 °C and held for 2 h. After settling, the supernatant was decanted and washed twice with 100 mL of hexane at 60 °C. After decanting, 3 mL of 1 M triethylaluminum solution was added, and the mixture was stirred for 4 h. After settling, the supernatant was decanted and washed four times with 100 mL of hexane at 50 °C. After drying, a solid catalyst with good flowability was obtained.

[0097] The performance of the alkoxymagnesium particle support and catalyst obtained in the examples and comparative examples is shown in Tables 1 and 2 below.

[0098] Table 1 Carrier performance

[0099]

[0100] Table 2 Catalyst Performance

[0101] serial number Tiwt% Ac / KgPE / gCat <![CDATA[BD / g / cm 3 ]]> Particle size <75μmwt% Example 1 5.4 32.1 0.37 0.76 Example 2 5.0 31.6 0.36 0.51 Example 3 5.2 32.4 0.36 0.26 Example 4 4.8 30.1 0.38 0.49 Example 5 5.3 31.4 0.35 0.36 Example 6 4.9 30.6 0.34 0.42 Example 7 6.8 31.9 0.37 0.21 Example 8 5.0 32.6 0.36 0.30 Example 9 4.9 31.8 0.38 0.52 Comparative Example 1 11.3 33.4 0.25 5.39 Comparative Example 2 4.9 31.2 0.31 3.13 Comparative Example 3 8.6 34.0 0.27 4.79 Comparative Example 4 5.3 30.3 0.31 0.48

[0102] As shown in Tables 1-2, compared with the comparative example, the catalyst prepared from the support provided in the embodiments of the present invention can effectively improve the polymer packing density while ensuring high catalyst activity, and the fine powder content is much lower than that of the comparative example. Therefore, the catalyst of the present invention has better overall performance.

[0103] The 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.

Claims

1. An alkoxymagnesium particle, characterized in that... The alkoxymagnesium particles have a particle size of 1–100 μm and a total pore volume of 0.1–4 cm³. 3 / g, specific surface area is 20-110m² 2 / g.

2. The alkoxymagnesium particles according to claim 1, characterized in that: The total pore volume of the alkoxymagnesium particles is 0.5–4 cm³. 3 / g; and / or, Specific surface area is 30-100 m² 2 / g; and / or, In the alkoxymagnesium particles, the volume of pores with a diameter of less than 1 μm has a volume ratio of more than 50 nm, preferably 60-99%.

3. The alkoxymagnesium particles according to claim 1, characterized in that: The alkoxymagnesium particles comprise the reaction products of the following components: magnesium powder, halogenating agent, mixed alcohol, organosiloxane compounds and / or organic epoxy compounds.

4. The alkoxymagnesium particles according to claim 3, characterized in that: The organosiloxane compounds are selected from methyltriethoxysilane, dimethyldiethoxysilane, trimethylethoxysilane, triethoxysilane, tetraethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, trimethoxysilane, tetramethoxysilane, methyltripropoxysilane, dimethyldipropoxysilane, trimethylpropoxysilane, tripropoxysilane, tetrapropoxysilane, methyltriisopropoxysilane, dimethyldiisopropoxysilane, trimethylisopropoxysilane, triisopropoxysilane, tetraisopropoxysilane, vinyltriisopropoxysilane, and propyltriethoxyisocyanate. At least one of the following: silane, n,n-dimethyl-3-aminopropyltrimethoxysilane, propyltriethoxysilane, ethyltriethoxysilane, diethyldiethoxysilane, triethylethoxysilane, ethyltrimethoxysilane, diethyldimethoxysilane, triethylmethoxysilane, ethyltripropoxysilane, diethyldipropoxysilane, triethylpropoxysilane, diethyldiisopropoxysilane, triethylisopropoxysilane, diallyldiethoxysilane, diisopropyldiethoxysilane, diisopropyldimethoxysilane, diallyldimethoxysilane, dimethyldi(allyloxy)silane; and / or, The organic epoxy compound is selected from at least one of propylene oxide, ethylene oxide, butane oxide, butadiene oxide, butadiene dioxide, epichlorohydrin, methyl glycidyl ether, and diglycidyl ether; and / or, The amount of each organosiloxane compound or organic epoxy compound per mole of magnesium is 0 to 1 mole, preferably 0 to 0.5 moles, but not both simultaneously 0.

5. The alkoxymagnesium particles according to claim 3, characterized in that: The magnesium powder has an average particle size of less than 300 μm; and / or, The halogenating agent is selected from at least one of elemental iodine, elemental bromine, chlorine, magnesium iodide, magnesium chloride, magnesium bromide, calcium bromide, calcium chloride, calcium iodide, manganese chloride, and magnesium alkoxyhalides; and / or, The mixed alcohol is a mixture of alcohols or a mixture of alcohols and phenols, wherein the alcohol is at least one of a straight-chain or branched monohydric alcohol or a polyhydric alcohol, preferably C1 to C2. 10 The alcohol, more preferably methanol, ethanol, n-propanol, isopropanol, n-butanol, n-pentanol, 1-hexanol, 1-octanol, 1-heptanol, 2-ethylhexanol, 2-pentanol, 2-butanol, 2-hexanol, 2-heptanol, 2-octanol, 4-methyl-2-pentanol, 2-phenylethanol, ethylene glycol, glycerol, 1-phenyl-1-propanol; the phenol is an unsubstituted or alkyl-substituted phenol, preferably phenol or C1-C1 phenol. 10 Alkyl-substituted phenols; and / or, The amount of the halogenating agent per mole of magnesium is 0.0001 to 0.05 moles, preferably 0.0001 to 0.02 moles; the amount of the mixed alcohol is 1 to 30 moles, preferably 3 to 15 moles.

6. The method for preparing alkoxymagnesium particles according to any one of claims 1 to 5, comprising reacting a component including magnesium powder, a halogenating agent, a mixed alcohol, an organosiloxane compound and / or an organic epoxy compound under an inert atmosphere, preferably at a temperature below 80°C.

7. A solid catalyst component comprising a reaction product of the following components: 1) alkoxymagnesium particles as described in any one of claims 1 to 5; 2) a titanium-containing compound; optionally 3) an internal electron donor compound.

8. The solid catalyst component according to claim 7, characterized in that: The general formula of the titanium-containing compound is Ti(OR1). y X 4-y In the formula, R1 represents C1 to C2. 10 The hydrocarbon group, where X is a halogen atom, 0≤y≤3; preferably, R1 is selected from C1~C6 alkyl, C2~C6 alkenyl, C3 ... 10 cycloalkyl, C6-C 10 The aromatic hydrocarbon group, more preferably, R1 is selected from methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, cyclopropyl, methylcyclopropyl, n-pentyl, methylcyclopentyl, cyclohexyl, phenyl, benzyl, or xylylyl; even more preferably, the titanium-containing compound is selected from at least one of TiCl4, Ti(OC2H5)Cl3, Ti(OCH3)Cl3, and Ti(OC4H9)Cl3; and / or, The internal electron-donating compound is selected from monocarboxylic acid esters and / or siloxanes; the monocarboxylic acid esters are preferably selected from methyl formate, ethyl formate, propyl formate, butyl formate, pentyl formate, hexyl formate, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, pentyl acetate, hexyl acetate, methyl propionate, ethyl propionate, propyl propionate, butyl propionate, pentyl propionate, hexyl butyrate, methyl butyrate, ethyl butyrate, propyl butyrate, butyl butyrate, pentyl butyrate, hexyl butyrate, methyl valerate, ethyl valerate, propyl valerate, butyl valerate, and valerate. At least one of the following: pentyl benzoate, hexyl pentanoate, methyl hexanoate, ethyl hexanoate, propyl hexanoate, butyl hexanoate, pentyl hexanoate, hexyl benzoate, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, pentyl benzoate, and hexyl benzoate; wherein the siloxane compound is preferably selected from tetramethyltriethoxysilane, dimethyldiethoxysilane, trimethylethoxysilane, triethoxysilane, tetraethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, trimethoxysilane, tetramethoxysilane, methyltripropoxysilane, and dimethyl... Dipropoxysilane, Trimethylpropoxysilane, Tripropoxysilane, Tetrapropoxysilane, Methyltriisopropoxysilane, Dimethyldiisopropoxysilane, Trimethylisopropoxysilane, Triisopropoxysilane, Tetraisopropoxysilane, Vinyltriisopropoxysilane, Propyltriethoxysilane, N,N-Dimethyl-3-aminopropyltrimethoxysilane, Propyltriethoxysilane, Ethyltriethoxysilane, Diethyldiethoxysilane, Triethylethoxysilane, Ethyltrimethoxysilane, Diethyldimethoxysilane, Triethylmethoxysilane, Ethyltripropoxysilane, Ethyltripropoxysilane Silane oxy-coated silane, diethyldipropoxysilane, triethylpropoxysilane, diethyldiisopropoxysilane, triethylisopropoxysilane, diallyldiethoxysilane, diisopropyldiethoxysilane, diisopropyldimethoxysilane, diallyldimethoxysilane, dimethyldi(allyloxy)silane, tetra(2-ethylhexyloxy)silane, n-propyltriethoxysilane, n-propyltrimethoxysilane, decyltrimethoxysilane, decyltriethoxysilane, cyclopentyltrimethoxysilane, cyclopentyltriethoxysilane, 2-methylcyclopentyltrimethoxysilane, 2,3-Dimethylcyclopentyltrimethoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, tert-butyltriethoxysilane, n-butyltrimethoxysilane, n-butyltriethoxysilane, isobutyltrimethoxysilane, isobutyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, monochlorotrimethoxysilane, monochlorotriethoxysilane, vinyltributoxysilane, trimethylphenoxysilane, methyltrienepropoxysilane, tert-butylmethyldimethoxysilane, tert-butylmethyldiethoxysilane, tert-pentylmethyldiethoxysilane, dicyclopentyldimethoxysilane, dicyclopentyl At least one of the following: diphenyldimethoxysilane, methylcyclopentyldiethoxysilane, methylcyclopentyldimethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, methylphenyldimethoxysilane, bis(o-tolyldimethoxysilane), bis(o-tolyldiethoxysilane), bis(m-tolyldimethoxysilane), bis(m-tolyldiethoxysilane), bis(p-tolyldimethoxysilane), bis(p-tolyldiethoxysilane), tricyclopentylmethoxysilane, tricyclopentylethoxysilane, dicyclopentylmethylmethoxysilane, and cyclopentyldimethylmethoxysilane; and / or, The amount of the titanium-containing compound used per mole of magnesium is 1 to 50 mol, preferably 1 to 20 mol; the amount of the internal electron donor compound used is 0 to 2 mol, preferably 0 to 1 mol.

9. A catalyst for olefin polymerization, comprising the following components: Component I: The solid catalyst component according to any one of claims 7-8; Component II: General formula AlR d X 3-d Organoaluminum compounds, among which, R is hydrogen or C1~C 20 Hydrocarbon group, X is a halogen atom, 0 < d ≤ 3; and / or, Preferably, the molar ratio of aluminum in component II to titanium in component I is 10:1 to 200:1, more preferably 20:1 to 100:1; and / or, In the organoaluminum compound, the repeated R is independently hydrogen or C1-C2. 10 The hydrocarbon group; preferably, the repeated R is independently hydrogen or a C1-C5 hydrocarbon group; more preferably, the organoaluminum compound is selected from at least one of Al(CH3)3, Al(CH2CH3)3, Al(i-Bu)3, AlH(CH2CH3)2, AlH(i-Bu)2, AlCl(CH2CH3)2, Al2Cl3(CH2CH3)3, and AlCl2(CH2CH3).

10. A method for olefin polymerization, comprising: Under olefin polymerization reaction conditions, one or more olefins are contacted with the catalyst of claim 9.

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