Catalyst component for the polymerization of olefins, process for its preparation, catalyst for the polymerization of olefins and use

Abstract

The application discloses a catalyst component for olefin polymerization and a preparation method thereof, a catalyst for olefin polymerization and application. The catalyst component for olefin polymerization is prepared from raw materials including an intermediate, an agglomerating agent and a reinforcing agent; the intermediate is prepared from raw materials including a magnesium halide alcohol compound and a titanium-containing compound. The catalyst component has simple and safe preparation process, and the catalyst particle morphology is spherical and not easy to be broken during catalytic olefin polymerization; the obtained polymer particle morphology is spherical, and the fine powder content is extremely low, and the catalyst is suitable for gas phase polymerization process and olefin slurry polymerization process.

Description

Technical Field

[0001] This invention relates to the technical field of catalyst components for olefin polymerization, and more specifically, to catalyst components for olefin polymerization, methods for their preparation, catalysts for olefin polymerization, and their applications. Background Technology

[0002] Both slurry polymerization and gas-phase polymerization of olefins require catalysts with good particle morphology that are not easily broken during polymerization and have a low content of fine polymer powder. This is especially important in the gas-phase polymerization of olefins.

[0003] European patent document EP1572756A discloses a catalyst prepared using a spherical magnesium chloride support. The catalyst prepared by this method has a good particle morphology, and the polymer production apparatus includes a pre-polymerization process to reduce catalyst breakage during the polymerization reaction and to reduce the content of fine polymer powder. The catalyst preparation process includes: first, reducing the ethanol content by heating the support, and then treating the support with an organoaluminum compound and titanium tetrachloride. The catalyst prepared by this method has high polymerization activity, but the preparation process uses hazardous organoaluminum compounds, and the support heating equipment is energy-intensive.

[0004] To eliminate the prepolymerization process in polymer production equipment, European patent document EP2285840A discloses another catalyst prepared using a spherical magnesium chloride support. The catalyst preparation process includes: first, reducing the ethanol content by heating the support; then, treating the support with titanium tetrachloride to obtain the catalyst; and finally, prepolymerizing using an organoaluminum compound. The catalyst prepared by this method exhibits high polymerization activity, but the prepolymerization uses a hazardous organoaluminum compound, and the support heating equipment is energy-intensive.

[0005] Chinese patent documents CN102020732A and CN102050897A both disclose catalysts prepared using spherical magnesium chloride supports, which exhibit high polymerization activity. Chinese patent document CN102020732A first treats the support with an organoaluminum compound, then treats the support with titanium tetrachloride to obtain the catalyst; this preparation process uses hazardous organoaluminum compounds, and its safety needs further improvement. Chinese patent document CN102050897A first heats the support to reduce the ethanol content, then treats the support with titanium tetrachloride to obtain the catalyst; this preparation process uses energy-intensive support heating equipment, and the equipment investment is substantial.

[0006] Therefore, providing a catalyst with a simple and safe preparation process, good catalyst particle morphology, that is not easily broken during olefin polymerization, and that yields a very low content of fine polymer powder is an important research direction in this field. Summary of the Invention

[0007] To address the problems existing in the prior art, this invention proposes catalyst components for olefin polymerization, their preparation methods, catalysts for olefin polymerization, and their applications. The catalyst component preparation process of this invention is simple and safe; the catalyst particles are spherical and not easily broken during olefin polymerization; the resulting polymer particles are spherical with very low fine powder content, making them suitable for gas-phase polymerization and olefin slurry polymerization processes.

[0008] One objective of this invention is to provide a catalyst component for olefin polymerization, said catalyst component for olefin polymerization being prepared from raw materials including intermediates, agglomerants, and reinforcing agents;

[0009] The intermediate is prepared from raw materials including magnesium halide alcohols and titanium-containing compounds.

[0010] In the catalyst component for olefin polymerization described in this invention, preferably,

[0011] The magnesium halide alkoxide is a reaction product of magnesium halide and a lower alcohol.

[0012] Preferably,

[0013] The content of lower alcohols in magnesium halide alcohols is 10 wt% to 60 wt%; for example, 10, 12, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60 wt% and any range between any two of the above values; or,

[0014] The molar ratio of lower alcohols to magnesium halides is 0.25 to 3, preferably 2 to 3, and more preferably 2 to 2.8.

[0015] In the catalyst component for olefin polymerization described in this invention, preferably,

[0016] The magnesium halide alkoxide is selected from at least one of magnesium chloride alkoxides;

[0017] Preferably, the lower alcohol is selected from at least one of methanol, ethanol, n-propanol, isopropanol, n-butanol, or isobutanol; most preferably, it is ethanol.

[0018] The preparation method of magnesium halide alcohols described in this invention refers to Chinese Patent CN1091748A (taking magnesium chloride alcohols as an example), and the steps are as follows: Anhydrous magnesium halide, such as magnesium dichloride, and alcohol are reacted with a certain ratio at high temperature to generate a magnesium chloride alcohol melt. After high-speed stirring and dispersion in a dispersant, the melt is rapidly cooled to form microspherical solid particles of magnesium chloride alcohols. After washing and drying, the magnesium chloride alcohol is obtained. The dispersant uses hydrocarbon solvents such as kerosene, paraffin oil, petrolatum oil, white oil, etc., and some surfactants or organosilicon compounds are also added. The alcohols include methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, and other high carbon fatty alcohols, with ethanol being preferred.

[0019] In the catalyst component for olefin polymerization described in this invention, preferably,

[0020] The titanium-containing compound is selected from general formula (I)Ti(OR). m Cl 4-m At least one of the compounds shown; where R is C2 to C3. 20 Hydrocarbon groups, 0≤m≤4;

[0021] Preferably, R is C2~C 10 Saturated or unsaturated straight-chain, branched, or cyclic hydrocarbon groups;

[0022] More preferably, R is a C2-C6 saturated or unsaturated straight-chain, branched, or cyclic hydrocarbon group;

[0023] More preferably, the titanium-containing compound is selected from at least one of titanium tetrachloride, tetraethyl titanate, or tetrabutyl titanate, with titanium tetrachloride being the most preferred.

[0024] In the catalyst component for olefin polymerization described in this invention, preferably,

[0025] The agglomerating agent is selected from at least one of C1-C8 alkyl ester compounds;

[0026] Preferably, the agglomerating agent is selected from at least one of C1-C6 alkyl ester compounds;

[0027] More preferably, the agglomerating agent is selected from at least one of methyl formate, ethyl formate, methyl acetate, ethyl acetate, n-propyl acetate, or isopropyl acetate, with ethyl acetate being the most preferred.

[0028] In the catalyst component for olefin polymerization described in this invention, preferably,

[0029] The reinforcing agent is selected from at least one of styrene-butadiene block copolymers;

[0030] Preferably,

[0031] In the styrene-butadiene block copolymer, the mass content of butadiene is 3-97%; preferably 10-90%; and / or,

[0032] The blocks in the styrene-butadiene block copolymer are linear or branched.

[0033] More preferably,

[0034] The styrene-butadiene block copolymer is selected from at least one of styrene-butadiene diblock copolymers and their derivatives, and styrene-butadiene-styrene triblock copolymers and their derivatives.

[0035] More preferably, the styrene-butadiene diblock copolymer derivative is selected from at least one of hydrogenated styrene-butadiene copolymer, maleic anhydride-grafted styrene-butadiene copolymer, or acrylic acid-grafted styrene-butadiene copolymer;

[0036] The styrene-butadiene-styrene triblock copolymer derivative is selected from at least one of hydrogenated styrene-butadiene-styrene copolymer, maleic anhydride-grafted styrene-butadiene-styrene copolymer, or acrylic acid-grafted styrene-butadiene-styrene copolymer.

[0037] In the catalyst component for olefin polymerization described in this invention, preferably,

[0038] The molar ratio of the titanium-containing compound to the magnesium halide alkoxide is 1 to 100; preferably 5 to 50; for example, 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, and any range between any two of the above values; and / or,

[0039] The weight ratio of the intermediate to the agglomerating agent is 0.5 to 50, preferably 1 to 25; for example, 0.5, 1, 2, 4, 6, 8, 10, 10, 15, 20, 25, 30, 35, 40, 45, 50, and any range between any two of the above values; and / or,

[0040] The weight ratio of the intermediate to the reinforcing agent is 10 to 1000, preferably 20 to 500; for example, it is 10, 20, 50, 100, 150, 200, 300, 400, 500, 600, 700, 800, 900, 1000, or any range between any two of the above values.

[0041] A second objective of this invention is to provide a method for preparing a catalyst component for olefin polymerization, comprising the following steps:

[0042] (1) The magnesium halide alkoxide and the titanium-containing compound are reacted in a solvent in one step. After solid-liquid separation, the separated solid and the titanium-containing compound are reacted in a solvent in a second step, washed, and dried to obtain an intermediate.

[0043] (2) Under a protective atmosphere, the reinforcing agent, intermediate and agglomerator are reacted in a solvent to obtain the catalyst component;

[0044] Preferred for the preparation of catalyst components for olefin polymerization as described in one of the objectives of this invention.

[0045] In the method for preparing the catalyst component for olefin polymerization according to the present invention, preferably,

[0046] In step (1), the molar ratio of the titanium-containing compound to the magnesium halide alkoxide is 1 to 100, preferably 5 to 50; and / or, the molar ratio of the titanium-containing compound used in the primary reaction to the titanium-containing compound used in the secondary reaction is 0.1 to 10, preferably 0.5 to 5;

[0047] Preferably,

[0048] The solvents used in the primary and secondary reactions are each independently selected from C4 to C6. 20 Alkane or aromatic solvents; preferably, the solvents used in the primary and secondary reactions are each independently selected from at least one of pentane, hexane, heptane, toluene, isobutane, and cyclohexane; and / or,

[0049] In a single reaction, the concentration of the magnesium halide alkoxide in the reaction system is 1 wt% to 15 wt%, preferably 2 wt% to 10 wt%; for example, 1, 2, 5, 10, 15 wt%, or any range between any two of the above values; and / or,

[0050] The temperatures for the primary and secondary reactions are each independently selected from (-80)℃ to 150℃, preferably (-50℃) to 120℃; for example, -80, -50, -30, 0, 30, 60, 90, 120, 150℃, and any range between any two of the above values; and / or,

[0051] The times for the primary and secondary reactions are each independently selected from 2h to 20h, preferably 4h to 10h; for example, 2, 4, 5, 10, 15, 20h, and any range between any two of the above values; and / or,

[0052] The drying process involves blowing with a protective gas.

[0053] In the method for preparing the catalyst component for olefin polymerization according to the present invention, preferably,

[0054] In step (2),

[0055] The weight ratio of the intermediate to the agglomerating agent is 0.5 to 50, preferably 1 to 25; for example, 0.5, 1, 2, 4, 6, 8, 10, 10, 15, 20, 25, 30, 35, 40, 45, 50, and any range between any two of the above values; and / or,

[0056] The weight ratio of the intermediate to the reinforcing agent is 10 to 1000, preferably 20 to 500; for example, 10, 20, 50, 100, 150, 200, 300, 400, 500, 600, 700, 800, 900, 1000, and any range between any two of the above values; and / or,

[0057] The concentration of the intermediate in the reaction system is 1 wt% to 15 wt%, preferably 2 wt% to 10 wt%; for example, 1, 2, 5, 10, 15 wt% and any range between any two of the above values; and / or, the reaction temperature is 0℃ to 90℃, preferably 10℃ to 50℃; for example, 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90℃ and any range between any two of the above values; and / or,

[0058] The reaction time is 0.5h to 6h, preferably 1h to 3h; for example, 0.5, 1, 2, 3, 4, 5, 6h and any range between any two of the above values;

[0059] Preferably,

[0060] In step (2), the dispersion of the reinforcing agent is mixed with the dispersion of the intermediate and the agglomerating agent and reacted. After washing and drying, the catalyst component is obtained.

[0061] More preferably,

[0062] The solvents used in the dispersions of the reinforcing agent and the intermediates are each independently selected from C4 to C6. 20 Alkane or aromatic solvents; preferably each independently selected from at least one of pentane, hexane, heptane, toluene, isobutane, and cyclohexane; and / or,

[0063] The drying process involves blowing with a protective gas.

[0064] A third objective of this invention is to provide a catalyst for olefin polymerization reactions:

[0065] Includes at least one of (a) the catalyst component for olefin polymerization described in any one of the objectives of the present invention, and the catalyst component for olefin polymerization prepared by any one of the methods described in any other objective of the present invention;

[0066] (b) At least one organoaluminum compound of the general formula AlR'3, wherein each of the three R's is independently selected from an alkyl group or a halogen-substituted alkyl group.

[0067] In the catalyst for olefin polymerization described in this invention, preferably,

[0068] The three R's in the organoaluminum compound are each independently selected from C1 to C8 alkyl groups or chlorine-substituted C1 to C8 alkyl groups; preferably, at least one of the three R's in the organoaluminum compound is a C1 to C8 alkyl group;

[0069] More preferably, the organoaluminum compound is selected from at least one of triethylaluminum, triisobutylaluminum, tri-n-hexylaluminum, tri-n-octylaluminum, diethylaluminum chloride, and diethylaluminum chloride; and / or,

[0070] In the catalyst used for olefin polymerization, the molar ratio of aluminum to titanium is 1 to 1000, preferably 10 to 100.

[0071] The fourth objective of this invention is to provide a catalyst component for olefin polymerization as described in any one of the present inventions; the second objective of this invention is to provide a catalyst component for olefin polymerization prepared by any one of the methods described in any one of the present inventions; and the third objective of this invention is to provide the application of a catalyst for olefin polymerization reaction as described in any one of the present inventions in olefin polymerization reaction. Preferably, the olefin is selected from one or more of ethylene, propylene, butene, hexene, or octene.

[0072] The catalyst of the present invention can be used with another co-catalyst or electron donor, or it can be used in combination with one or more Ziegler-Natta catalysts or non-Ziegler-Natta catalysts.

[0073] The catalyst described herein can be used in different polymerization processes, including gas-phase polymerization and slurry polymerization. The catalyst system described herein can be used for the polymerization or copolymerization of olefins.

[0074] The endpoints and any values ​​of the ranges disclosed in this invention are not limited to the precise ranges or values; 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. In the following, various technical solutions can, in principle, be combined with each other to obtain new technical solutions, which should also be considered as specifically disclosed herein.

[0075] Compared with the prior art, the present invention has at least the following advantages:

[0076] Existing technologies use organoaluminum compounds to treat the support during the catalyst preparation stage, and then load titanium-containing compounds such as titanium tetrachloride. This invention does not use organoaluminum compounds during the catalyst component preparation stage, and is therefore safer.

[0077] The catalyst component and the corresponding catalyst in this invention do not require a catalyst prepolymerization process and can be directly applied to olefin polymerization. The catalyst component uses a titanium-containing compound (such as titanium tetrachloride) to treat a spherical magnesium halide alcohol support twice. Its preparation process does not involve a heating and de-alcoholization step, making the preparation process simpler and less costly.

[0078] This invention discovers that after preparing an intermediate by treating a spherical magnesium halide alcohol support twice with a titanium-containing compound (such as titanium tetrachloride), it is then treated with an agglomerator and a reinforcing agent. The agglomerator reduces catalyst fines, thereby lowering the polymer fines content. Further treatment with the reinforcing agent reduces catalyst breakage during polymerization, further reducing the fines content in the polymer. The agglomerator and reinforcing agent can be added simultaneously or first, with the same effect.

[0079] The catalyst component preparation process of this invention is simple and safe, the catalyst particles are spherical and not easily broken during olefin polymerization; the resulting polymer particles are spherical with very low fine powder content, making them suitable for gas-phase polymerization and olefin slurry polymerization processes. Detailed Implementation

[0080] 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.

[0081] It should also be noted that the various specific technical features described in the following embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the various possible combinations will not be described separately in this invention.

[0082] Furthermore, various embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention. The resulting technical solutions are part of the original disclosure of this specification and also fall within the protection scope of the present invention.

[0083] 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.

[0084] Test method:

[0085] 1. Particle size distribution of support and catalyst: MASTERSIZE particle size analyzer, n-hexane as dispersant, measurement range 0.01~3500μm.

[0086] 2. The content of metal (titanium) in the catalyst system: Inductively coupled plasma atomic emission spectrometry (ICP).

[0087] 3. Method for determining bulk density: DIN-53194

[0088] The synthesis method of magnesium chloride alcohols used in this invention is as follows:

[0089] In a 250 mL glass reactor equipped with a reflux condenser, mechanical stirrer, and thermometer, and purged with nitrogen, 37.8 mL of anhydrous ethanol and 21.3 g of anhydrous magnesium chloride were added. The mixture was heated with stirring until the magnesium chloride was completely dissolved. Then, 75 mL of white oil and 75 mL of silicone oil were added, and the temperature was maintained at 120 °C for a certain period of time. In another 500 mL reaction flask equipped with a high-speed stirrer, 112.5 mL of white oil and the same volume of silicone oil were added beforehand and preheated to 120 °C. The mixture prepared above was then rapidly pressed into a second reactor and stirred at 4000 rpm for three minutes while maintaining the temperature at 120 °C. The mixture was then transferred with stirring to a third reactor, which had been pre-filled with 1600 mL of hexane and cooled to -25 °C. The transfer was repeated until the final temperature did not exceed 0 °C. The silicone oil and white oil were washed away with hexane and the mixture was then dried under vacuum to obtain 45.7 g of spherical magnesium chloride alcohol. The composition of the magnesium chloride alcohol was determined to be MgCl22.56C2H5OH, with an average particle size of 50.1 μm and an alcohol content of 56.0 wt%.

[0090] Example 1

[0091] Preparation of catalyst components

[0092] (1) Preparation of intermediates

[0093] Under nitrogen protection, 5.0 g of magnesium chloride ethanolate and 50 mL of n-hexane were added to a 500 mL glass reactor, and the mixture was cooled to -30 °C. 50 mL of titanium tetrachloride was slowly added and stirred for 2 hours. The mixture was then slowly heated to 70 °C and stirred for 2 hours. The mixture was cooled to 50 °C, allowed to stand, and then the mother liquor was filtered off by pressure. 50 mL of n-hexane was added, followed by another 50 mL of titanium tetrachloride, and the reaction proceeded as described above. After the reaction was complete, the mixture was washed three times with 50 mL of n-hexane, dried under nitrogen, and yielded 3.8 g of a free-flowing intermediate.

[0094] (2) Preparation of catalyst

[0095] Under nitrogen protection, the intermediate obtained in step (1) and 50 mL of n-hexane were added to a 500 mL glass reactor, followed by 0.5 mL of ethyl acetate and 1 mL of a 10 g / L hexane solution of styrene-butadiene-styrene triblock copolymer (Kraton FG1901X, with butadiene content of 70%). The mixture was heated to 50 °C and stirred for 2 hours. After the reaction was completed, the reactor was washed three times with 50 mL of n-hexane and dried under nitrogen to obtain a catalyst with good flowability and an average particle size of 36.7 μm.

[0096] Elemental analysis (ICP): Ti: 3.96% (by weight).

[0097] Ethylene polymerization

[0098] 1 L of hexane, 1 mmol of triethylaluminum, and a certain amount (10 mg) of catalyst component were added to a 2 L stainless steel stirred tank, and the temperature was raised to 85 °C. Hydrogen gas at 0.28 MPa was added, and ethylene was added to maintain the total pressure of the system at 1.03 MPa. The polymerization reaction was carried out for 2 hours. After the reaction, the polyethylene powder was dried, collected, and weighed to calculate the polymerization activity. The catalyst prepared above was used for the polymerization reaction, and the corresponding polymerization activity and polymer bulk density results are shown in Table 1. The polymer sieving results are shown in Table 2.

[0099] Example 2

[0100] Preparation of catalyst components

[0101] Except for changing the amount of ethyl acetate from 0.5 ml to 1 ml, the other conditions were the same as in Example 1, and the average particle size was 37.5 micrometers.

[0102] Elemental analysis (ICP): Ti: 3.89% (by weight).

[0103] The ethylene slurry polymerization reaction conditions for the catalyst were the same as in Example 1. The catalyst prepared above was used for the polymerization reaction, and the corresponding polymerization activity and polymer bulk density results are shown in Table 1. The polymer sieving results are shown in Table 2.

[0104] Example 3

[0105] Preparation of catalyst components

[0106] Except for changing the amount of ethyl acetate from 0.5 ml to 1.5 ml, the other conditions were the same as in Example 1, and the average particle size was 38.4 micrometers.

[0107] Elemental analysis (ICP): Ti: 3.77% (by weight).

[0108] The ethylene slurry polymerization reaction conditions for the catalyst were the same as in Example 1. The catalyst prepared above was used for the polymerization reaction, and the corresponding polymerization activity and polymer bulk density results are shown in Table 1. The polymer sieving results are shown in Table 2.

[0109] Example 4

[0110] Preparation of catalyst components

[0111] Except for changing the amount of ethyl acetate from 0.5 ml to 2 ml, the other conditions were the same as in Example 1, and the average particle size was 39.2 micrometers.

[0112] Elemental analysis (ICP): Ti: 3.62% (by weight).

[0113] The ethylene slurry polymerization reaction conditions for the catalyst were the same as in Example 1. The catalyst prepared above was used for the polymerization reaction, and the corresponding polymerization activity and polymer bulk density results are shown in Table 1. The polymer sieving results are shown in Table 2.

[0114] Example 5

[0115] Preparation of catalyst components

[0116] Except for changing the amount of ethyl acetate from 0.5 ml to 2.5 ml, the other conditions were the same as in Example 1, and the average particle size was 40.3 micrometers.

[0117] Elemental analysis (ICP): Ti: 3.51% (by weight).

[0118] The ethylene slurry polymerization reaction conditions for the catalyst were the same as in Example 1. The catalyst prepared above was used for the polymerization reaction, and the corresponding polymerization activity and polymer bulk density results are shown in Table 1. The polymer sieving results are shown in Table 2.

[0119] Example 6

[0120] Preparation of catalyst components

[0121] Except for changing the amount of hexane solution of styrene-butadiene-styrene triblock copolymer to 2 ml, the other conditions were the same as in Example 1, and the average particle size was 36.8 micrometers.

[0122] Elemental analysis (ICP): Ti: 4.00% (by weight).

[0123] The ethylene slurry polymerization reaction conditions for the catalyst were the same as in Example 1. The catalyst prepared above was used for the polymerization reaction, and the corresponding polymerization activity and polymer bulk density results are shown in Table 1. The polymer sieving results are shown in Table 2.

[0124] Example 7

[0125] Preparation of catalyst components

[0126] Except for changing the amount of hexane solution of styrene-butadiene-styrene triblock copolymer to 5 ml, the other conditions were the same as in Example 1, and the average particle size was 37.2 micrometers.

[0127] Elemental analysis (ICP): Ti: 4.05% (by weight).

[0128] The ethylene slurry polymerization reaction conditions for the catalyst were the same as in Example 1. The catalyst prepared above was used for the polymerization reaction, and the corresponding polymerization activity and polymer bulk density results are shown in Table 1. The polymer sieving results are shown in Table 2.

[0129] Comparative Example 1

[0130] Preparation of catalyst components

[0131] Except for the absence of ethyl acetate and the hexane solution of styrene-butadiene-styrene triblock copolymer, the conditions were the same as in Example 1, and the average particle size was 35.8 micrometers.

[0132] Elemental analysis (ICP): Ti: 4.17% (by weight).

[0133] The ethylene slurry polymerization reaction conditions for the catalyst were the same as in Example 1. The catalyst prepared above was used for the polymerization reaction, and the corresponding polymerization activity and polymer bulk density results are shown in Table 1. The polymer sieving results are shown in Table 2.

[0134] Comparative Example 2

[0135] Preparation of catalyst components

[0136] Except for the absence of ethyl acetate, the conditions were the same as in Example 1, and the average particle size was 36.0 micrometers.

[0137] Elemental analysis (ICP): Ti: 4.05% (by weight).

[0138] The ethylene slurry polymerization reaction conditions for the catalyst were the same as in Example 1. The catalyst prepared above was used for the polymerization reaction, and the corresponding polymerization activity and polymer bulk density results are shown in Table 1. The polymer sieving results are shown in Table 2.

[0139] Comparative Example 3

[0140] Preparation of catalyst components

[0141] Except for the absence of a hexane solution containing styrene-butadiene-styrene triblock copolymer, the conditions were the same as in Example 1, and the average particle size was 36.6 micrometers.

[0142] Elemental analysis (ICP): Ti: 3.98% (by weight).

[0143] The ethylene slurry polymerization reaction conditions for the catalyst were the same as in Example 1. The catalyst prepared above was used for the polymerization reaction, and the corresponding polymerization activity and polymer bulk density results are shown in Table 1. The polymer sieving results are shown in Table 2.

[0144] The catalysts prepared above were used in the polymerization reaction, and the corresponding polymerization activity and polymer packing density results are shown in Table 1.

[0145] Table 1. Polymerization activity and polymer packing density of the catalyst

[0146] Example 1 13.9 0.35 Example 2 13.8 0.34 Example 3 13.5 0.34 Example 4 13.2 0.33 Example 5 13.0 0.33 Example 6 13.6 0.34 Example 7 11.9 0.32 Comparative Example 1 14.2 0.36 Comparative Example 2 14.0 0.35 Comparative Example 3 14.2 0.36

[0147] Table 2. Particle size distribution of polymers (weight percentage)

[0148]

[0149] The results above show that adding only a hexane solution of styrene-butadiene-styrene triblock copolymer as a reinforcing agent during catalyst preparation can reduce the content of polymer fines, but cannot eliminate polymer fines smaller than 150 μm. However, adding ethyl acetate as a flocculant not only increases the size of the catalyst particles but also increases the size of the polymer particles, thus eliminating polymer fines smaller than 150 μm.

[0150] When the catalyst prepared by the method of this invention is used for ethylene polymerization, it maintains high polymerization activity while producing polymer particles with larger particle sizes and less fine polymer powder. This catalyst is suitable for gas-phase polymerization and olefin slurry polymerization processes.

[0151] The present invention has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and embodiments of the present invention without departing from the spirit and scope of the invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.

[0152] 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.

[0153] 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.

[0154] 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.

Claims

1. A catalyst component for olefin polymerization, characterized in that: The catalyst component for olefin polymerization is prepared from raw materials including intermediates, agglomerants, and reinforcing agents. Magnesium halide alkoxides and titanium-containing compounds are reacted in a solvent in a first reaction. After solid-liquid separation, the separated solid and titanium-containing compounds are reacted in a second reaction in a solvent, washed, and dried to obtain an intermediate. The molar ratio of titanium-containing compounds to magnesium halide alcohols in the two reactions is 1 to 100; the molar ratio of titanium-containing compounds used in the first reaction to those used in the second reaction is 0.1 to 10. The temperatures for the primary and secondary reactions are each independently selected from -80℃ to 150℃; the times for the primary and secondary reactions are each independently selected from 2h to 20h. The agglomerating agent is selected from at least one of methyl formate, ethyl formate, methyl acetate, ethyl acetate, n-propyl acetate, or isopropyl acetate; The reinforcing agent is selected from at least one of styrene-butadiene block copolymers; in the styrene-butadiene block copolymer, the mass content of butadiene is 10-90%; The styrene-butadiene block copolymer is selected from at least one of styrene-butadiene diblock copolymers and their derivatives, and styrene-butadiene-styrene triblock copolymers and their derivatives. The weight ratio of the intermediate to the agglomerating agent is 0.5 to 50; The weight ratio of the intermediate to the reinforcing agent is 10 to 1000.

2. The catalyst component for olefin polymerization according to claim 1, characterized in that: The magnesium halide alkoxides are the reaction products of magnesium halide and lower alcohols.

3. The catalyst component for olefin polymerization according to claim 2, characterized in that: The content of lower alcohols in magnesium halide alcohols is 10wt% to 60wt%; or, The molar ratio of lower alcohols to magnesium halides is 0.25 to 3.

4. The catalyst component for olefin polymerization according to claim 3, characterized in that: The molar ratio of lower alcohols to magnesium halides is 2 to 3.

5. The catalyst component for olefin polymerization according to claim 4, characterized in that: The molar ratio of lower alcohols to magnesium halides is 2 to 2.

8.

6. The catalyst component for olefin polymerization according to claim 2, characterized in that: The magnesium halide alkoxide is selected from at least one of magnesium chloride alkoxides.

7. The catalyst component for olefin polymerization according to claim 6, characterized in that: The lower alcohol is selected from at least one of methanol, ethanol, n-propanol, isopropanol, n-butanol, or isobutanol.

8. The catalyst component for olefin polymerization according to claim 1, characterized in that: The titanium-containing compound is selected from general formula (I)Ti(OR). m Cl 4-m At least one of the compounds shown; where R is C2 to C3. 20 The hydrocarbon group, 0≤m≤4.

9. The catalyst component for olefin polymerization according to claim 8, characterized in that: R is C2~C 10 Saturated or unsaturated straight-chain or branched hydrocarbon groups.

10. The catalyst component for olefin polymerization according to claim 9, characterized in that: R is a saturated or unsaturated straight-chain or branched hydrocarbon group from C2 to C6.

11. The catalyst component for olefin polymerization according to claim 10, characterized in that: The titanium-containing compound is selected from at least one of titanium tetrachloride, tetraethyl titanate, or tetrabutyl titanate.

12. The catalyst component for olefin polymerization according to claim 1, characterized in that: The styrene-butadiene diblock copolymer derivative is selected from at least one of hydrogenated styrene-butadiene copolymer, maleic anhydride-grafted styrene-butadiene copolymer, or acrylic acid-grafted styrene-butadiene copolymer. The styrene-butadiene-styrene triblock copolymer derivative is selected from at least one of hydrogenated styrene-butadiene-styrene copolymer, maleic anhydride-grafted styrene-butadiene-styrene copolymer, or acrylic acid-grafted styrene-butadiene-styrene copolymer.

13. The catalyst component for olefin polymerization according to claim 1, characterized in that: The molar ratio of the titanium-containing compound to the magnesium halide alkoxide in the two reactions is 5–50; and / or, The weight ratio of the intermediate to the agglomerating agent is 1 to 25; and / or, The weight ratio of the intermediate to the reinforcing agent is 20 to 500.

14. A method for preparing a catalyst component for olefin polymerization, characterized in that, Includes the following steps: (1) The magnesium halide alkoxide and the titanium-containing compound are reacted in a solvent in one step. After solid-liquid separation, the separated solid and the titanium-containing compound are reacted in a solvent in a second step, washed, and dried to obtain an intermediate. (2) Under a protective atmosphere, the reinforcing agent, intermediate and agglomerating agent are reacted in a solvent to obtain the catalyst component; Used for the preparation of the catalyst component for olefin polymerization as described in any one of claims 1-13.

15. The method for preparing the catalyst component for olefin polymerization according to claim 14, characterized in that, In step (1), the molar ratio of the titanium-containing compound to the magnesium halide alkoxide is 5 to 50; and / or, the molar ratio of the titanium-containing compound used in the primary reaction to the titanium-containing compound used in the secondary reaction is 0.5 to 5. The solvents used in the primary and secondary reactions are each independently selected from aromatic solvents or C4-C4 solvents. 20 Alkanes; and / or, In a single reaction, the concentration of the magnesium halide alkoxide in the reaction system is 1 wt% to 15 wt%; and / or, The drying process involves blowing with a protective gas.

16. The method for preparing the catalyst component for olefin polymerization according to claim 15, characterized in that, In step (1), The solvents used in the primary and secondary reactions are each independently selected from at least one of pentane, hexane, heptane, toluene, isobutane, and cyclohexane; and / or, In a single reaction, the concentration of the magnesium halide alkoxide in the reaction system is 2 wt% to 10 wt%; and / or, The temperatures for the primary and secondary reactions are each independently selected from -50℃ to 120℃; and / or, The time for the primary and secondary reactions is independently selected from 4h to 10h.

17. The method for preparing the catalyst component for olefin polymerization according to claim 16, characterized in that, In step (2), The weight ratio of the intermediate to the agglomerating agent is 0.5 to 50; and / or, The weight ratio of the intermediate to the reinforcing agent is 10 to 1000; and / or, The concentration of the intermediate in the reaction system is 1 wt% to 15 wt%; and / or, The reaction temperature is 0℃~90℃; and / or, The reaction time is 0.5 h to 6 h.

18. The method for preparing the catalyst component for olefin polymerization according to claim 17, characterized in that, In step (2), The weight ratio of the intermediate to the agglomerating agent is 1 to 25; and / or, The weight ratio of the intermediate to the reinforcing agent is 20–500; and / or, The concentration of the intermediate in the reaction system is 2 wt% to 10 wt%; and / or, The reaction temperature is 10℃~50℃; and / or, The reaction time is 1 hour to 3 hours; and / or, In step (2), the dispersion of the reinforcing agent is mixed with the dispersion of the intermediate and the agglomerating agent and reacted. After washing and drying, the catalyst component is obtained.

19. The method for preparing the catalyst component for olefin polymerization according to claim 18, characterized in that, The solvents used in the dispersions of the reinforcing agent and the intermediates are each independently selected from aromatic solvents or C4-C4 solvents. 20 Alkane solvent.

20. The method for preparing the catalyst component for olefin polymerization according to claim 19, characterized in that, The solvents used in the dispersions of the reinforcing agent and the intermediates are each independently selected from at least one of pentane, hexane, heptane, toluene, isobutane, and cyclohexane.

21. A catalyst for olefin polymerization, characterized in that: Includes at least one of (a) the catalyst component for olefin polymerization according to any one of claims 1-13, and the catalyst component for olefin polymerization prepared by the method according to claims 14-20; (b) At least one organoaluminum compound of the general formula AlR'3, wherein each of the three R's is independently selected from an alkyl group or a halogen-substituted alkyl group.

22. The catalyst for olefin polymerization according to claim 21, characterized in that: In organoaluminum compounds, each of the three R's is independently selected from C1-C8 alkyl groups or chlorine-substituted C1-C8 alkyl groups; and / or, In the catalyst used for olefin polymerization, the molar ratio of aluminum to titanium is 1 to 1000.

23. The catalyst for olefin polymerization according to claim 22, characterized in that: In organoaluminum compounds, at least one of the three R's is a C1-C8 alkyl group; and / or, In the catalyst used for olefin polymerization, the molar ratio of aluminum to titanium is 10 to 100.

24. The catalyst for olefin polymerization according to claim 23, characterized in that: The organoaluminum compound is selected from at least one of triethylaluminum, triisobutylaluminum, tri-n-hexylaluminum, tri-n-octylaluminum, diethylaluminum chloride, and diethylaluminum chloride.

25. The use of a catalyst component for olefin polymerization as described in any one of claims 1-13, a catalyst component for olefin polymerization prepared by the method described in claims 14-20, or a catalyst for olefin polymerization reaction as described in any one of claims 21-24 in an olefin polymerization reaction.

26. The application according to claim 25, characterized in that: The olefin is selected from one or more of ethylene, propylene, butene, hexene, or octene.

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