Component of olefin polymerization catalyst, olefin polymerization catalyst and application of olefin polymerization catalyst

Abstract

The invention discloses a component of an olefin polymerization catalyst, the olefin polymerization catalyst and application of the olefin polymerization catalyst, the component of the olefin polymerization catalyst comprises Mg, Ti, halogen and an internal electron donor, and the internal electron donor is an ascorbic acid ester compound. The components of the olefin polymerization catalyst contain the biosafety internal electron donor component, so that the toxicity of residual components of the catalyst in polyolefin can be reduced, and the olefin polymerization catalyst is particularly suitable for production of medical polyolefin materials.

Description

Technical Field

[0001] The invention belongs to the field of polyolefin catalysts and relates to a solid catalyst component for olefin polymerization, a preparation method thereof, an olefin polymerization catalyst and application thereof. Background Art

[0002] Polyolefins are a type of polymer material with the largest output and widest application due to their abundant raw materials, low prices, easy processing and molding, and excellent comprehensive performance. Among them, polyethylene and polypropylene are the most important. Taking polypropylene as an example, polypropylene has excellent properties, such as radiation resistance, high heat resistance, high pressure resistance, physiological degradability, good mechanical properties and chemical stability, and is increasingly widely used in the medical field. Polypropylene is mainly used as medical non-woven fabrics, disposable medical products, medical transparent tubes, blood filters and artificial lungs in the medical field. When polypropylene is used to manufacture disposable medical products, syringe needles, catheters and other medical products, it has the characteristics of light weight, not easy to break, high temperature resistance, non-toxicity, easy processing, low price, and can avoid medical cross infection during use. However, the hygienic performance indicators of ordinary polypropylene cannot meet the standards for the production of medical products, which limits its application.

[0003] One of the difficulties in producing medical clean polypropylene is that the ash control requirements are extremely high. The total ash content of polypropylene resin and the residual components of the catalyst are the key indicators of clean polypropylene production. If clean polypropylene is obtained directly in the kettle without using the elution procedure, it is often necessary to use a high-activity catalyst for production. In order to fundamentally improve the properties of the active center of the Ziegler-Natta catalyst (ZN catalyst) to significantly increase the polymerization activity, adding internal electron donors during the catalyst preparation process and adding external electron donors during the polymerization process will have a great impact on the olefin polymerization behavior and polymer properties. Among them, changing the internal electron donor in the catalyst can change the properties of the catalyst active center to the greatest extent possible, thereby changing the performance of the catalyst to the greatest extent.

[0004] Therefore, the development of new electron donors has always been a hot topic in the research and development of ZN polypropylene catalysts. The relatively distinctive high-performance internal electron donor compounds in the prior art mainly include: 1) fatty acid esters and aromatic acid ester compounds, mainly represented by phthalate compounds; 2) diether compounds (such as EP0361493, EP0728724); 3) succinate compounds (such as WO9856834, WO0063261, WO03022894); 4) glycol ester compounds (such as WO9856834, WO0063261, WO03022894); 5) compounds with other functional groups (CN1105671, CN1242780, US20060128558), etc. However, in practical applications, the above compounds have certain problems as internal electron donors for olefin polymerization catalysts. Although the catalysts using 1,3-diether compounds as internal electron donors have higher activity and good hydrogen tuning sensitivity, the relative molecular mass distribution of the produced PP is narrow, which is not conducive to the development of different grades of PP; the advantage of using succinate compounds as internal electron donors is that the relative molecular mass distribution of the synthesized PP is relatively wide, but the disadvantage is that the stereoregularity of PP and the hydrogen tuning sensitivity of the catalyst need to be improved; and the overall activity of the diol ester catalytic system is not as ideal as the diether system.

[0005] At present, the most widely used polyolefin internal electron donor in industry is phthalate compounds, which have medium activity, good stereoselectivity and low price for the catalysts prepared by them. However, phthalate compounds, as commonly used plasticizers, are very harmful to human reproductive health and the environment, and there is a great demand for replacement. Europe has restricted the use of most phthalate substances.

[0006] In order to improve the performance of polyolefin catalysts, the weight ratio of internal electron donor compounds in the solid catalyst in the prior art is about 5-20%, which, as a polymerization residual component, will have a negative impact on the cleanliness of polypropylene, especially when a catalyst containing a high amount of phthalate internal electron donors is used, a component with a certain degree of reproductive toxicity will remain in the polyolefin, limiting its medical use. Therefore, the development of a catalyst containing a highly biosafe internal electron donor compound and having high activity will be beneficial to the production of medical polyolefin products and promote the development of medical polyolefin materials. Summary of the invention

[0007] In order to solve the problems existing in the prior art, the present invention provides an olefin polymerization catalyst containing a biosafe internal electron donor component and its application. The olefin polymerization catalyst can reduce the toxicity of the catalyst residual components in polyolefins and is particularly suitable for the production of medical polyolefin materials.

[0008] The object of the present invention is to provide a component of an olefin polymerization catalyst.

[0009] Another object of the present invention is to provide a catalyst comprising the component.

[0010] Another object of the present invention is to provide the catalyst in CH 2 =Application of CHR in olefin polymerization.

[0011] In order to achieve the object of the present invention, the present invention provides a component of an olefin polymerization catalyst, which comprises Mg, Ti, a halogen and an internal electron donor, wherein the internal electron donor is at least one ascorbic acid ester compound selected from the general formula (I), the general formula (II) and the general formula (III):

[0012]

[0013] Among them, R 1 , R 2 , R 3 and R 4 The same or different, each independently selected from C 1 -C 20 Preferably, R 1 , R 2 , R 3 and R 4 may also contain at least one heteroatom selected from N, O, S, P, Si and halogen; preferably, R 1 , R 2 , R 3 and R 4 Two or more of them may be bonded to each other to form a ring.

[0014] Preferably, R 1 , R 2 , R 3 and R 4 The same or different, each independently selected from linear or branched alkyl, cycloalkyl, alkenyl, ester, phenyl, alkylphenyl, phenylalkyl, indenyl, benzyl, halogenated or substituted by N, O, S, P, Si heteroatom, alkyl, cycloalkyl, phenyl, alkylphenyl, phenylalkyl, indenyl, benzyl with less than 20 carbon atoms; or each independently selected from heterocyclic aromatic substituents.

[0015] Preferably, R 1 , R 2 , R 3 and R 4 are the same or different and are each independently selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, cyclopentyl, n-hexyl, cyclohexyl, heptyl, octyl, nonyl, decyl, C 11 ~C20 a linear or branched alkyl or alkenyl group, phenyl, m-chlorophenyl, p-chlorophenyl, o-chlorophenyl, m-methoxyphenyl, p-methoxyphenyl, o-methoxyphenyl, p-methylphenyl, p-nitrophenyl, m-nitrophenyl, substituted benzyl, substituted phenethyl, furyl, pyrrolyl, thienyl, propenyl, butenyl, pentenyl, hexenyl, or indenyl.

[0016] Preferably, the ascorbic acid monoester compound of the general formula (I) is preferably selected from methyl ascorbate, ethyl ascorbate, n-propyl ascorbate, isopropyl ascorbate, n-butyl ascorbate, isobutyl ascorbate, tert-butyl ascorbate, n-pentyl ascorbate, isopentyl ascorbate, cyclopentyl ascorbate, n-hexyl ascorbate, cyclohexyl ascorbate, heptyl ascorbate, octyl ascorbate, nonyl ascorbate, decyl ascorbate, lauryl ascorbate, myristyl ascorbate, palmityl ascorbate, ascorbic acid, At least one of stearic acid ester, phenyl ascorbate, benzyl ascorbate, phenylacetic acid ascorbate, o-chlorophenyl ascorbate, m-chlorophenyl ascorbate, p-toluene ascorbate, p-methoxyphenyl ascorbate, p-methylphenyl ascorbate, m-trimethylphenyl kojic acid, p-nitrophenyl kojic acid, p-fluorophenyl kojic acid, p-trifluoromethylphenyl kojic acid, crotonyl ascorbate, naphthyl ascorbate, nicotinoyl ascorbate, monoethyl ascorbyl succinate, cinnamyl ascorbate, thiophene ascorbate, and furfuryl ascorbate.

[0017] Preferably, the ascorbic acid diester compound of the general formula (II) is preferably selected from dimethyl ascorbate, diethyl ascorbate, di-n-propyl ascorbate, diisopropyl ascorbate, di-n-butyl ascorbate, diisobutyl ascorbate, di-tert-butyl ascorbate, di-n-pentyl ascorbate, diisopentyl ascorbate, dicyclopentyl ascorbate, di-n-hexyl ascorbate, dicyclohexyl ascorbate, diheptyl ascorbate, dioctyl ascorbate, dinonyl ascorbate, didecyl ascorbate, dilauryl ascorbate, dimyristyl ascorbate, dipalmityl ascorbate, di-n ...-n-pentyl ascorbate, di-n-pentyl ascorbate, di-n-pentyl ascorbate, di-n-pentyl ascorbate, di-n-pentyl ascor At least one of stearic acid ester, diphenyl ascorbate, dibenzyl ascorbate, diphenylacetate ascorbate, di-o-chlorophenyl ascorbate, di-m-chlorophenyl ascorbate, di-p-tolyl ascorbate, di-p-methoxyphenyl ascorbate, di-p-methylphenyl ascorbate, m-trimethylphenyl ascorbate, p-nitrophenyl ascorbate, p-fluorophenyl ascorbate, p-trifluoromethylphenyl ascorbate, dicrotyl ascorbate, dinaphthyl ascorbate, dinicotinoyl ascorbate, monoethyl ascorbyl disuccinate, dicinnamyl ascorbate, dithiophene ascorbate, and difurfuryl ascorbate.

[0018] Preferably, the ascorbic acid tetraester compound of the general formula (III) is preferably selected from tetramethyl ascorbate, tetraethyl ascorbate, tetra-n-propyl ascorbate, tetraisopropyl ascorbate, tetra-n-butyl ascorbate, tetraisobutyl ascorbate, tetra-tert-butyl ascorbate, tetra-n-pentyl ascorbate, tetraisopentyl ascorbate, tetracyclopentyl ascorbate, tetra-n-hexyl ascorbate, tetracyclohexyl ascorbate, tetraheptyl ascorbate, tetraoctyl ascorbate, tetranonyl ascorbate, tetradecyl ascorbate, tetralauryl ascorbate, tetramyristyl ascorbate, tetrapalmityl ascorbate, At least one of ascorbyl tetrastearate, tetraphenyl ascorbate, tetrabenzyl ascorbate, tetraphenylacetate ascorbate, tetra-o-chlorophenyl ascorbate, tetra-m-chlorophenyl ascorbate, tetra-p-tolyl ascorbate, tetra-p-methoxyphenyl ascorbate, tetra-p-methylphenyl ascorbate, m-trimethylphenyl kojic acid, p-nitrophenyl kojic acid, p-fluorophenyl kojic acid, p-trifluoromethylphenyl kojic acid, tetracrotyl ascorbate, tetranaphthyl ascorbate, tetranicotinoyl ascorbate, tetraethyl ascorbate succinate, tetracinnamyl ascorbate, tetrathiophene ascorbate, and tetrafurfuryl ascorbate.

[0019] The present invention does not limit the source or preparation method of the ascorbic acid ester compound, which can be a commercially available product; or can be prepared using ascorbic acid as a raw material through a main method such as an ester exchange reaction method, a direct esterification method, an acyl chloride esterification method, an enzyme catalysis method, etc.

[0020] Preferably, the ascorbic acid ester compound is prepared by the acyl chloride esterification method, when R 1 , R 2 , R 3 and R 4 At the same time, four equivalents of acyl chloride are used for one-step reaction to obtain the ascorbic acid tetraester compound of general formula (III), and the reaction process is as follows:

[0021]

[0022] Preferably, the composition of the components of the olefin polymerization catalyst comprises a titanium compound, a magnesium compound, and an ascorbic acid ester compound;

[0023] The precursor of the magnesium compound is selected from X n Mg(OR a ) 2-n MgCl 2 ·mR a OH, R a 2-n MgX n MgCl 2 / SiO 2 MgCl 2 / Al 2 O 3, at least one of a mixture of magnesium halide and titanium alkoxide, wherein m is 0.1-6, 0≤n≤2, X is a halogen, R a C 1 -C 20 The hydrocarbon group;

[0024] The general formula of the titanium compound is TiX N (OR b ) 4-N , where R b C 1 -C 20 The hydrocarbon group is: X is halogen, and N is 1-4.

[0025] Preferably, the magnesium compound is an alcoholate of magnesium dihalide; or, the magnesium compound is a liquid magnesium compound; or, the magnesium compound is a derivative of the magnesium dihalide molecule in which at least one halogen atom is replaced by a hydrocarbonoxy group or a halogenated hydrocarbonoxy group; preferably, it is a hydrocarbonoxy magnesium compound; more preferably, it is an alkoxy magnesium and / or an aryloxy magnesium.

[0026] Preferably, the titanium compound comprises at least one of titanium tetrachloride, titanium tetrabromide, titanium tetraiodide or alkyl titanium halide;

[0027] Preferably, the alkyl titanium halide includes at least one of methoxytitanium trichloride, ethoxytitanium trichloride, propoxytitanium trichloride, n-butoxytitanium trichloride, dimethoxytitanium dichloride, diethoxytitanium dichloride, dipropoxytitanium dichloride, di-n-butoxytitanium dichloride, trimethoxytitanium chloride, triethoxytitanium chloride, tripropoxytitanium chloride, and tri-n-butoxytitanium chloride;

[0028] Preferably, the titanium compound is titanium tetrachloride.

[0029] Preferably, the halogen is at least one of chlorine, bromine and iodine.

[0030] Preferably, in the components of the olefin polymerization catalyst, the molar ratio of the sum of the internal electron donors to the magnesium compound is 0.01-5.0, preferably 0.05-3.0, and the magnesium compound is calculated as magnesium element.

[0031] Preferably, when the internal electron donor is a mixture of two compounds of general formula (I), general formula (II) and general formula (III), the molar ratio of the two internal electron donors is 20:1 to 1:20. In other words, when the internal electron donor is a mixture of two compounds of general formula (I), general formula (II) and general formula (III), the internal electron donor has the following ways of adding: when the internal electron donor is an ascorbate compound of general formula (I) or general formula (II), the molar ratio of the ascorbate compound of general formula (I) to general formula (II) is 20:1 to 1:20;

[0032] When the internal electron donor is an ascorbyl ester compound of the general formula (I) or the general formula (III), the molar ratio of the ascorbyl ester compound of the general formula (I) to the general formula (III) is 20:1 to 1:20;

[0033] When the internal electron donor is an ascorbic acid ester compound of the general formula (II) or (III), the molar ratio of the ascorbic acid ester compound of the general formula (II) to the general formula (III) is 20:1 to 1:20.

[0034] Preferably, when the internal electron donor is a mixture of three of the general formula (I), general formula (II) and general formula (III), the molar ratio of the feed amount of any one of the general formula (I), general formula (II) and general formula (III) to the total feed amount is ≥1 / 20.

[0035] The present invention does not particularly limit the preparation method of the components of the olefin polymerization catalyst, which can be prepared according to the following preparation methods:

[0036] Method 1: Magnesium alcoholate or chloroalcoholate and excess TiCl 4 and at least one ascorbic acid ester compound of the general formula (I), the general formula (II) and the general formula (III) at a temperature of 80-135°C. According to a preferred method, the general formula TiX N (OR b ) 4-N Titanium compounds (where R b C 1 -C 20 A hydrocarbon group, X is a halogen, and N is 1-4; preferably TiCl 4 ) and the general formula is MgCl 2 ·mR a OH (wherein m is a number of 0.1-6, preferably 2-4, and R a C 1 -C 20 The adduct can be suitably made into a spherical shape by mixing an alcohol and magnesium chloride in the presence of an inert hydrocarbon immiscible with the adduct, and rapidly quenching the emulsion to solidify the adduct in the form of spherical particles. The spherical MgCl prepared according to this process 2 ·mR aExamples of OH adducts are described in US Pat. No. 4,399,054 A and US Pat. No. 4,469,648 A. The adduct thus obtained can be reacted directly with the titanium compound, or it can be previously subjected to a thermally controlled dealcoholation (80-130° C.) to obtain an adduct in which the number of moles of alcohol is generally less than 3, preferably between 0.1 and 2.5. The adduct can be prepared by suspending the adduct (dealcoholated or as such) in a cold TiCl 4 The reaction with the titanium compound is carried out in a temperature range of -25-0°C; the mixture is heated to 80-130°C and maintained at this temperature for 0.5-2 hours. 4 The treatment can be performed once or multiple times. 4 At least one ascorbic acid ester compound of the general formula (I), general formula (II) and general formula (III) may be added during the treatment, and this treatment may be repeated once or multiple times.

[0037] Method 2: dissolving a magnesium compound in a solvent system consisting of an organic epoxy compound, an organic phosphine compound and an inert diluent to form a uniform solution, mixing with a titanium compound, and precipitating a solid in the presence of a precipitation aid; the solid is treated with at least one ascorbic acid ester compound of the general formula (I), the general formula (II) and the general formula (III) to load it on the solid, and if necessary, treated with titanium tetrahalide and an inert diluent to obtain the solid, wherein the precipitation aid is one of an organic anhydride, an organic acid, an ether and a ketone. The components are calculated per mole of magnesium halide, and the organic epoxy compound is 0.2-10 moles, the organic phosphine compound is 0.1-3 moles, the precipitation aid is 0-1.0 moles, and the Ti compound is 0.5-150 moles.

[0038] Method 3: Using TiCl 4 A solution of titanium alkoxide in an aromatic hydrocarbon (e.g., toluene, xylene, etc.) can be reacted with a magnesium dialkoxide compound such as magnesium dialkoxide (preferably magnesium ethoxide) or magnesium diaryloxide at -25-0°C and halogenated at 80-130°C. 4 The treatment with the aromatic hydrocarbon solution can be repeated once or multiple times, and at least one ascorbic acid ester compound of the general formula (I), general formula (II) and general formula (III) can be added once or in batches during multiple such treatments. For example, the preparation method of the titanium-containing solid catalyst component disclosed in US5077357A can be referred to: ethoxymagnesium, tetraethoxytitanium, o-cresol, ethanol and chlorobenzene are added in sequence, and stirred; TiCl 4 / chlorobenzene solution is quickly added to the above liquid, and the temperature is raised until it is completely dissolved, and then the temperature is continued to be raised to a specific temperature; using N 2 After bubbling away the ethanol reactant, continue stirring for a certain period of time, then wash once with hot chlorobenzene, wash twice with isooctane, and then N 2The carrier can be obtained by drying. Or according to another example: TiCl 4 , tetraethoxytitanium, ethoxymagnesium and o-cresol are added to chlorobenzene and stirred; ethanol is added and stirred for 3 hours at high temperature after the ethoxymagnesium is dissolved; hot filtering is then washed once with warm chlorobenzene, once with isooctane, and finally N 2 dry.

[0039] Method 4: Pre-activate magnesium dichloride according to the existing method, and then use excess TiCl 4 Treatment, wherein the solution contains at least one ascorbic acid ester compound of the general formula (I), the general formula (II) and the general formula (III). 4 The solid was treated several times and washed with hexane to remove any unreacted TiCl 4 .

[0040] Method 5: The preparation method of the titanium-containing solid catalyst component disclosed in CN1208045A can be referred to: first, a liquid magnesium compound and a liquid titanium compound are contacted at low temperature in the presence of a compound selected from alcohols, phenols, ketones, aldehydes, ethers, amines, pyridines and esters to precipitate a solid. The contact temperature is generally -70 to 200°C, preferably -30 to 130°C. During the contact process, the ascorbic acid ester compound of the general formula (I), the general formula (II) and the general formula (III) is used for treatment.

[0041] Method 6: Grind anhydrous magnesium chloride and at least one ascorbic acid ester compound of the general formula (I), general formula (II) and general formula (III) together under conditions where magnesium dichloride is activated. The product thus obtained can be treated with excess TiCl at a temperature of 80-130°C. 4 The product is treated one or more times. After the treatment, it is washed with a hydrocarbon solvent until it is free of chloride ions. According to a further method, the product obtained by co-grinding anhydrous magnesium dichloride, a titanium compound and at least one ascorbyl ester compound of the general formula (I), the general formula (II) and the general formula (III) is treated with a halogenated hydrocarbon such as 1,2-dichloroethane, chlorobenzene, dichloromethane. The treatment is carried out at a temperature between 40°C and the boiling point of the halogenated hydrocarbon for 1 to 4 hours. The product is then usually washed with an inert hydrocarbon solvent such as hexane.

[0042] Method 7: Using SiO 2 , alumina or other inorganic oxides or porous silica gel as a carrier, and then activated by a well-known method, and then heated at a temperature of about 80-135 ° C with an excess of TiCl 4 During the treatment, at least one ascorbic acid ester compound of the general formula (I), the general formula (II) and the general formula (III) is added.

[0043] The above-mentioned reactions lead to the formation of magnesium halide in an active form (generally, crystalline magnesium halide has a regular structure and can carry very little Ti, so the catalytic activity is low. To prepare a highly active supported catalyst, the magnesium halide must be activated. The activation treatment method includes using physical and / or chemical methods to make it into microcrystals so that the active center is loaded on the surface, edge and defect of the magnesium halide. The treated magnesium halide microcrystals suitable for loading Ti are "active magnesium halide"). In addition to these reactions, other methods are also known in the literature to form magnesium halide in an active form from compound starting materials other than magnesium halide.

[0044] In any preparation method, the internal electron donor compound can be added directly or in an alternative manner, such as in situ by using a suitable precursor, which can be converted into the desired internal electron donor compound by known chemical reactions such as esterification, transesterification, etc. Generally, relative to MgCl 2 For example, the internal electron donor compound is used in a molar ratio of 0.01 to 5, preferably in a molar ratio of 0.05 to 3.0.

[0045] In any preparation method, at least one ascorbic acid ester compound of formula (I), formula (II) and formula (III) can be added simultaneously or separately in the preparation process in one batch or in several batches, in any order and in any combination.

[0046] The present invention also provides a catalyst for olefin polymerization, the raw material composition of which includes the components of the above catalyst and an organic aluminum compound.

[0047] According to a specific embodiment of the present invention, preferably, the general formula of the organoaluminum compound is AlR c p X (3-p) , where R c is hydrogen or C 1 -C 20 wherein X is a halogen and p is an integer of 0≤p≤3.

[0048] According to a specific embodiment of the present invention, preferably, the organoaluminum compound comprises at least one of a trialkylaluminum compound, an alkylaluminum halide, an alkylaluminum hydride, an alkylaluminum sesquichloride, and an alkylaluminumoxane; more preferably, the trialkylaluminum compound comprises at least one of trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-butylaluminum, tri-n-hexylaluminum, and trioctylaluminum; the alkylaluminum halide comprises AlEt 2 Cl; the alkylaluminum sesquichloride comprises Al 2 Et 3 Cl 3More preferably, the trialkylaluminum compound is AlEt 2 Cl and Al 2 Et 3 Cl 3 mixture.

[0049] According to a specific embodiment of the present invention, preferably, the molar ratio of the organoaluminum compound to the titanium atoms in the components of the catalyst is 1-1000:1, more preferably 50-800.

[0050] According to a specific embodiment of the present invention, preferably, the raw material composition of the catalyst also includes an external electron donor.

[0051] According to a specific embodiment of the present invention, preferably, the external electron donor is a siloxane compound.

[0052] According to a specific embodiment of the present invention, preferably, the general formula of the siloxane compound is R' t Si(OR”) 4-t , wherein R' and R" are each independently selected from C 1 -C 18 A hydrocarbon group, t is an integer of 0≤t≤3; more preferably, R' and R" each contain a heteroatom; more preferably, the heteroatom includes at least one of N, O, S, P, and Si.

[0053] According to a specific embodiment of the present invention, preferably, the siloxane compound includes trimethylmethoxysilane, trimethylethoxysilane, tri-n-propylmethoxysilane, tri-n-propylethoxysilane, tri-n-butylmethoxysilane, triisobutylethoxysilane, tricyclohexylmethoxysilane, tricyclohexylethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, di-n-propyldimethoxysilane, diisopropyldimethoxysilane, di-n-propyldiethoxysilane, diisopropyldiethoxysilane, di-n-butyldiethoxysilane, diisobutyldiethoxysilane, di-tert-butyldimethoxysilane, di-tert-butyldimethoxysilane, di-n-butyldimethoxysilane, diisobutyldimethoxysilane silane, di-tert-butyldiethoxysilane, di-n-butyldiethoxysilane, n-butylmethyldimethoxysilane, di(2-ethylhexyl)dimethoxysilane, di(2-ethylhexyl)diethoxysilane, dicyclohexyldimethoxysilane, dicyclohexyldiethoxysilane, dicyclopentyldimethoxysilane, dicyclopentyldiethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyldiethoxysilane, cyclohexylethyldimethoxysilane, cyclohexylisopropyldimethoxysilane, cyclohexylethyldiethoxysilane, cyclopentylmethyldimethoxysilane, cyclopentylethyldiethoxysilane, cyclopentylisopropyldiethoxysilane, cyclopentylisobutyldimethoxysilane, cyclohexyl-n-propyl Dimethoxysilane, cyclohexyl-n-propyldiethoxysilane, cyclohexyl-n-butyldiethoxysilane, amylmethyldimethoxysilane, amylmethyldiethoxysilane, amylethyldimethoxysilane, amylethyldiethoxysilane, cyclohexyldimethylmethoxysilane, cyclohexyldiethylmethoxysilane, cyclohexyldiethylmethoxysilane, cyclohexyldiethylethoxysilane, 2-ethylhexyltrimethoxysilane, cyclohexyldimethoxysilane, cyclohexyldiethoxysilane, 2-ethylhexyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, isopropyltrimethoxysilane, isopropyltriethoxysilane, n-butyl trimethoxysilane, isobutyltrimethoxysilane, tert-butyltrimethoxysilane, n-butyltriethoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, cyclopentyltrimethoxysilane, cyclopentyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-ethylhexyltrimethoxysilane, 2-ethylhexyltriethoxysilane, pentyltrimethoxysilane, pentyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, cyclohexylcyclopentyldimethoxysilane, cyclohexylcyclopentyldiethoxysilane, cyclohexylcyclopentyldipropoxysilane, 3-methylcyclohexylcyclopentyldimethoxysilane, 4-methylcyclohexylcyclopentyldimethoxysilane, 3,At least one of 5-dimethylcyclohexylcyclopentyldimethoxysilane, 3-methylcyclohexylcyclohexyldimethoxysilane, bis(3-methylcyclohexyl)dimethoxysilane, 4-methylcyclohexylcyclohexyldimethoxysilane, bis(4-methylcyclohexyl)dimethoxysilane, 3,5-dimethylcyclohexylcyclohexyldimethoxysilane, bis(3,5-dimethylcyclohexyl)dimethoxysilane, tetrapropoxysilane and tetrabutoxysilane.

[0054] According to a specific embodiment of the present invention, preferably, the siloxane compound includes at least one of di-n-propyldimethoxysilane, diisopropyldimethoxysilane, di-n-butyldimethoxysilane, diisobutyldimethoxysilane, di-tert-butyldimethoxysilane, di-n-butyldiethoxysilane, tert-butyltrimethoxysilane, dicyclohexyldimethoxysilane, dicyclohexyldiethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylethyldiethoxysilane, cyclohexylethyldimethoxysilane, cyclohexylethyldiethoxysilane, cyclopentylmethyldimethoxysilane, cyclopentylmethyldiethoxysilane, cyclopentylethyldimethoxysilane, cyclohexylcyclopentyldimethoxysilane, cyclohexylcyclopentyldiethoxysilane, 3-methylcyclohexylcyclopentyldimethoxysilane, 4-methylcyclohexylcyclopentyldimethoxysilane and 3,5-dimethylcyclopentyldimethoxysilane.

[0055] According to a specific embodiment of the present invention, preferably, the siloxane compound includes at least one of cyclohexylmethyldimethoxysilane, diisopropyldimethoxysilane, di-n-butyldimethoxysilane, diisobutyldimethoxysilane, diphenyldimethoxysilane, phenyltriethoxysilane, methyl-tert-butyldimethoxysilane, dicyclopentyldimethoxysilane, 2-ethylpiperidinyl-2-tert-butyldimethoxysilane, (1,1,1-trifluoro-2-propyl)-2-ethylpiperidinyldimethoxysilane, (1,1,1-trifluoro-2-propyl)-methyl-methoxysilane, cyclohexyltrimethoxysilane, tert-butyltrimethoxysilane and tert-hexyltrimethoxysilane.

[0056] According to a specific embodiment of the present invention, preferably, the molar ratio of silicon in the external electron donor to titanium in the catalyst component is 0.002-100, more preferably 0.01-20, and further preferably 0.01-5.

[0057] The invention also provides application of the catalyst in olefin polymerization.

[0058] According to a specific embodiment of the present invention, preferably, the olefin includes at least one of a linear or branched olefin, such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 3-methyl-1-butene, 4-methyl-1-pentene, butadiene, vinylcyclopentene, and vinylcyclohexene.

[0059] According to a specific embodiment of the present invention, preferably, the polymerization comprises ethylene and / or propylene polymerization.

[0060] According to a specific embodiment of the present invention, preferably, the polymerization includes homopolymerization or copolymerization.

[0061] According to a specific embodiment of the present invention, preferably, during the catalytic process, the order of adding the components in the catalyst is arbitrary, and it is preferred that the organoaluminum compound is first added to the polymerization system, then the external electron donor is added, and finally the catalyst components are added.

[0062] According to a specific embodiment of the present invention, preferably, in the above application, the polymerization process can be carried out with or without a solvent; the olefin monomer can be in gas phase or liquid phase; more preferably, hydrogen can be further added as a molecular weight regulator (polymerization can also be carried out without a molecular weight regulator); continuous polymerization or batch polymerization process can be applied, and the polymerization reaction can be carried out in one step, two steps or multiple steps.

[0063] According to a specific embodiment of the present invention, preferably, the polymerization temperature is ≤200°C, more preferably 20-100°C, and further preferably 40-80°C; the polymerization pressure is ≤10MPa, more preferably 0.3-5MPa.

[0064] Ascorbic acid ester compounds are a class of non-toxic, harmless, multifunctional nutritional antioxidant preservatives. Many of these compounds, such as ascorbyl palmitate, are nutritional antioxidants recognized by the Joint Committee on Food Additives of the World Health Organization. They are resistant to high temperatures and are suitable for use in medicines, health products, cosmetics, etc. They are also suitable as antioxidants for baking and frying oils. They are commonly used in oil-containing foods, edible oils, animal and vegetable oils, and high-end cosmetics. They can also be used in infant food and milk powder.

[0065] The inventor unexpectedly discovered that by using a variety of ascorbic acid ester compounds as internal electron donors in the preparation of olefin polymerization catalysts, the obtained olefin polymerization catalysts have better activity and selectivity, and the catalytic performance is adjusted by the number of ester functional groups. Ascorbic acid ester compounds have a five-membered ring oxygen-hetero main skeleton with multiple oxygen-containing functional groups. According to the number of ester functional groups, they can be divided into ascorbic acid monoesters, ascorbic acid diesters and ascorbic acid tetraesters. The different numbers of ester functional groups make the compounds have different electron-donating abilities, and the catalytic performance, especially the activity, can be controllably adjusted.

[0066] Some ascorbic acid ester compounds are commonly used food and drug additives on the market. Other substituted compounds can be prepared by selecting corresponding acyl chlorides and reacting with ascorbic acid. The cost is low, and the acyl chloride substituents have a wide range of choices, which is conducive to optimizing the internal electron donor structure by screening various substituents to further improve the catalyst performance, and is particularly suitable for industrial applications. Ascorbic acid ester compounds are highly stable and non-toxic to the human body. Catalysts using them as internal electron donors are particularly suitable for the production of medical polypropylene with high requirements for cleanliness and biotoxicity. DETAILED DESCRIPTION

[0067] The technical solution of the present invention is described in detail below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the implementation of the present invention, rather than all the embodiments.

[0068] The operations for preparing the catalysts in the following examples were all carried out under the protection of high-purity nitrogen.

[0069] Determination of polymer isotacticity: Determination by heptane extraction method (6 hours of boiling heptane extraction). Two grams of dry polymer sample are placed in an extractor and extracted with boiling heptane for 6 hours. The residue is dried to constant weight. The ratio of the polymer weight (g) to 2 is the isotacticity.

[0070] The bulk density of the polymer was determined using the JB / T 2412-2008 method.

[0071] The molecular weight distribution of the polymer was determined by a PL-220 gel permeation chromatograph using trichlorobenzene as solvent at 150°C (standard sample: polystyrene, flow rate 1.0 mL / min, column: 3xPlgel 10um M1Xed-B 300x7.5nm).

[0072] The ascorbyl ester compounds described in the present invention, such as L-ascorbyl palmitate, ascorbyl dipalmitate, ascorbyl tetrapalmitate, etc., are commercially available products. Non-commercially available ascorbyl ester compounds can also be prepared using ascorbic acid as a raw material through main methods such as ester exchange reaction method, direct esterification method, acyl chloride esterification method, enzyme catalysis method, etc.

[0073] Synthesis of Ascorbic Acid Ester Compounds

[0074] Preparation Example 1. Synthesis of Ascorbyl Palmitate

[0075] Palmitic acid (2.6 g, 10 mmol), 15 mL of dimethylethylenediamine and 5 mL of dichloromethane were added to a single-mouth flask in sequence and stirred and dissolved at room temperature. Dichlorothionyl (950 μL, 13 mmol) was slowly added dropwise under ice-water bath cooling, and the mixture was reacted at 10°C for 30 minutes. L-ascorbic acid (2.1 g, 12 mmol) was directly added, and the temperature was raised and maintained at 25°C for 6 hours. After the reaction was completed, 50 mL of ethyl acetate and 40 mL of distilled water were added to the reaction mixture, and the mixture was transferred to a separating funnel. The separated water layer was extracted once again with 50 mL of ethyl acetate, and the organic layer was combined. The organic layer was washed with saturated saline solution until there was no L-ascorbic acid and dimethylethylenediamine (thin layer chromatography tracking), dried over anhydrous sodium sulfate, and the organic solvent was evaporated to obtain a crude product. The crude product was purified by column chromatography to obtain a white powder with a yield of 80% and a melting point of 112-115°C. Its structure and nuclear magnetic resonance results are shown in Table 1.

[0076] Preparation Example 2-12. Preparation of other ascorbic acid ester compounds

[0077] Ascorbic acid monoesters are prepared by the aforementioned route or the route shown in reaction formula I, and the starting materials are selected from one equivalent (slightly excessive) of the corresponding acid or acyl chloride and ascorbic acid; ascorbic acid diesters are prepared by the aforementioned route, and the starting materials are selected from two equivalents (slightly excessive) of the corresponding acid or acyl chloride and ascorbic acid; ascorbic acid tetraesters are prepared by the aforementioned route, and the starting materials are selected from four equivalents (slightly excessive) of the corresponding acid or acyl chloride and ascorbic acid. The structures and NMR results of the compounds obtained in Preparation Examples 2-12 are shown in Table 1.

[0078]

[0079] Table 1 Ascorbic acid ester compounds

[0080]

[0081]

[0082]

[0083]

[0084]

[0085] Catalyst preparation

[0086] Example 1

[0087] In a 500 ml 5-necked flask with stirring and fully replaced with nitrogen, add 10 g MgCl 2 2.5C 2 H 5OH microspheres and 150mL titanium tetrachloride were used to prepare a suspension, then maintained at -15°C for one hour, slowly heated to 80°C, added 2g (5mmol) of ascorbyl palmitate, and then continued to heat to 110°C and kept constant for 1 hour, then the liquid was filtered clean, and the obtained solid was washed 3 times with 120mL titanium tetrachloride at 110°C. The obtained solid was washed 4 times with 150mL hexane at 60°C, the liquid was filtered off and dried to obtain the components of the olefin polymerization catalyst. The analytical evaluation data of the components of the olefin polymerization catalyst are shown in Table 2.

[0088] Example 2-12

[0089] The preparation process of the components of the olefin polymerization catalyst is as shown in Example 1, except that 5 mmol of ascorbyl palmitate is replaced by 5 mmol of the compounds No. 2-12 in Table 1 in sequence.

[0090] Example 13

[0091] The preparation process of the components of the olefin polymerization catalyst is as shown in Example 1, except that 5 mmol of ascorbyl palmitate is replaced by 3 mmol of ascorbyl palmitate and 2 mmol of ascorbyl dipalmitate.

[0092] Embodiment 14

[0093] The preparation process of the components of the olefin polymerization catalyst is as shown in Example 1, except that 5 mmol of ascorbyl palmitate is replaced by 3 mmol of ascorbyl dipalmitate and 2 mmol of ascorbyl tetraisopalmitate.

[0094] Embodiment 15

[0095] The preparation process of the components of the olefin polymerization catalyst is as shown in Example 1, except that 5 mmol of ascorbyl palmitate is replaced by 3 mmol of ascorbyl palmitate and 2 mmol of ascorbyl tetraisopalmitate.

[0096] Example 16

[0097] The preparation process of the components of the olefin polymerization catalyst is as shown in Example 1, except that 5 mmol of ascorbyl palmitate is replaced by 2 mmol of ascorbyl palmitate, 2 mmol of ascorbyl dipalmitate and 1 mmol of ascorbyl tetraisopalmitate.

[0098] Embodiment 17

[0099] In a 500mL 5-necked flask with stirring and fully replaced with nitrogen, add 10g of anhydrous magnesium chloride, 150mL of toluene, 17mL of epichlorohydrin and 16mL of tributyl phosphate at room temperature, heat to 50°C with stirring, and maintain for 2 hours. The solid is completely dissolved, then 2.40g of phthalic anhydride is added and maintained for another hour. The solution is cooled to -25°C, 110mL of titanium tetrachloride is added dropwise within 1 hour, and the temperature is slowly raised to 80°C. During the heating process, the solid is gradually washed out. 2g of ascorbic acid palmitate is added and maintained at 80°C for 1 hour. After filtering, wash twice with 200mL of toluene, then add 120mL of toluene and 80mL of titanium tetrachloride, continue to heat to 110°C, keep constant temperature for 2 hours, then filter the liquid clean, and repeat the process once. Filter off the liquid, wash the obtained solid once with 100mL of dichloroethane, wash 4 times with hexane, and dry to obtain the components of olefin polymerization catalyst. The titanium content, internal electron donor content and polymerization data of the components of the olefin polymerization catalyst are shown in Table 2.

[0100] Embodiment 18

[0101] In a 500ml 5-necked flask with nitrogen fully replaced and stirred, 8g of diethoxymagnesium and 100mL of toluene were added to prepare a suspension, 25mL of titanium tetrachloride was added dropwise at -15°C, the temperature was slowly raised to 0°C after the addition was completed, and 50mL of titanium tetrachloride was added dropwise, and then the temperature was slowly raised to 80°C, 2g of ascorbyl palmitate was added, and then the temperature was continued to rise to 110°C and kept constant for 2 hours, and then the liquid was filtered clean, the liquid was filtered off, and the obtained solid was washed 3 times with 100mL of titanium tetrachloride at 125°C. The obtained solid was washed 4 times with 120mL of hexane at 60°C, the liquid was filtered off and dried, and the components of the olefin polymerization catalyst were obtained.

[0102] Comparative Example 1

[0103] The preparation process of the components of the olefin polymerization catalyst is the same as that of Example 1, except that ascorbyl palmitate is replaced by 5 mmol of di-n-butyl phthalate (DN).

[0104] Comparative Example 2

[0105] The preparation process of the components of the olefin polymerization catalyst was the same as in Example 1, except that ascorbyl palmitate was replaced by 5 mmol of 9,9-dimethoxyfluorene (FLU).

[0106] Comparative Example 3

[0107] The preparation process of the components of the olefin polymerization catalyst was the same as in Example 1, except that ascorbyl palmitate was replaced by 5 mmol of acetyl tributyl citrate.

[0108] polymerization

[0109] The components of the olefin polymerization catalysts obtained in Examples 1-18 and Comparative Examples 1-3 were used for polymerization evaluation:

[0110] After nitrogen is fully replaced in a 5L stainless steel reactor, 5mL of 0.5mol / L triethylaluminum hexane solution and 1mL of 0.1mol / L cyclohexylmethyldimethoxysilane hexane solution and 10mg of the prepared olefin polymerization catalyst component are added, and then 10mL of hexane is added to flush the feed line, and then 2L (under standard conditions) of hydrogen and 2.5L of refined propylene are added, and the reaction is controlled to prepolymerize at 25°C for 5 minutes, and the temperature is raised to 70°C, and the polymerization reaction is carried out at this temperature for 1 hour. After the reaction is completed, the reactor is cooled and the stirring is stopped to discharge the reaction product, and the polymer is obtained by drying.

[0111] Table 2

[0112]

[0113]

[0114] From the results in Table 2, it can be seen that the catalysts of ascorbyl compounds as internal electron donors in Examples 1 to 12 are significantly more active than the catalysts of acetyl tributyl citrate (Comparative Example 3, a class of biosafety additives) as internal electron donor compounds under the same preparation conditions, and the activity is substantially higher than the catalysts of the most commonly used phthalate internal electron donors in the industry (Comparative Example 1). It can be seen that ascorbyl compounds can be used as efficient substitutes for phthalate internal electron donors with reproductive toxicity. Fluorene diether catalysts are currently commonly used in the development of low-ash polyolefin products due to their high activity. The catalyst activities of the ascorbyl compounds of internal electron donors in Examples 1 to 12 of the present invention are comparable to or higher than those of the fluorene diether catalyst (Comparative Example 2). Therefore, the ascorbyl compounds of the present invention have high biosafety as a class of internal electron donors, and the prepared catalysts have high activity, and are particularly suitable for the production of medical polyolefin products. It can be seen from each group of three examples (e.g., Examples 1 to 3, Examples 4 to 6, Examples 7 to 9, and Examples 10 to 12) that the more ester groups the same type of ascorbic acid ester compound has, the higher the catalytic activity; it can be seen from Examples 13 to 16 that the catalytic activity can also be adjusted by compounding ascorbic acid ester compounds with different numbers of ester groups.

[0115] The present invention is not limited to the aforementioned specific embodiments, and any changes or modifications made by any technician in the field of the present invention are all covered by the patent scope of the present invention.

Claims

1. A component of an olefin polymerization catalyst, characterized in that: The invention comprises Mg, Ti, halogen and an internal electron donor, wherein the internal electron donor is at least one ascorbic acid ester compound selected from the group consisting of general formula (I), general formula (II) and general formula (III): Among them, R 1 , R 2 , R 3 and R 4 The same or different, each independently selected from C1-C 20 of hydrocarbon groups.

2. The olefin polymerization catalyst component according to claim 1, characterized in that R 1 , R 2 , R 3 and R 4 They also each contain at least one heteroatom selected from N, O, S, P, Si and halogen.

3. The component of the olefin polymerization catalyst according to claim 1, characterized in that R 1 , R 2 , R 3 and R 4 Two or more of them are bonded to each other to form a ring.

4. The component of the olefin polymerization catalyst according to claim 1, characterized in that R 1 , R 2 , R 3 and R 4 The same or different, each independently selected from linear or branched alkyl, cycloalkyl, alkenyl, ester, phenyl, alkylphenyl, phenylalkyl, indenyl, benzyl, halogenated or substituted by N, O, S, P, Si heteroatom, alkyl, cycloalkyl, phenyl, alkylphenyl, phenylalkyl, indenyl, benzyl with less than 20 carbon atoms; or each independently selected from heterocyclic aromatic substituents.

5. The component of the olefin polymerization catalyst according to claim 1, characterized in that R 1 , R 2 , R 3 and R 4 are the same or different and are each independently selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, cyclopentyl, n-hexyl, cyclohexyl, heptyl, octyl, nonyl, decyl, C 11 ~C 20 a linear or branched alkyl or alkenyl group, phenyl, m-chlorophenyl, p-chlorophenyl, o-chlorophenyl, m-methoxyphenyl, p-methoxyphenyl, o-methoxyphenyl, p-methylphenyl, p-nitrophenyl, m-nitrophenyl, substituted benzyl, substituted phenethyl, furyl, pyrrolyl, thienyl, propenyl, butenyl, pentenyl, hexenyl, or indenyl.

6. The component of the olefin polymerization catalyst according to claim 1, characterized in that The ascorbic acid monoester compound of the general formula (I) is selected from methyl ascorbate, ethyl ascorbate, n-propyl ascorbate, isopropyl ascorbate, n-butyl ascorbate, isobutyl ascorbate, tert-butyl ascorbate, n-pentyl ascorbate, isopentyl ascorbate, cyclopentyl ascorbate, n-hexyl ascorbate, cyclohexyl ascorbate, heptyl ascorbate, octyl ascorbate, nonyl ascorbate, decyl ascorbate, lauryl ascorbate, myristyl ascorbate, palmityl ascorbate, stearyl ascorbate, oct ... At least one of fatty acid ester, phenyl ascorbate, benzyl ascorbate, phenylacetate ascorbate, o-chlorophenyl ascorbate, m-chlorophenyl ascorbate, p-toluene ascorbate, p-methoxyphenyl ascorbate, p-methylphenyl ascorbate, m-trimethylphenyl kojic acid, p-nitrophenyl kojic acid, p-fluorophenyl kojic acid, p-trifluoromethylphenyl kojic acid, crotonyl ascorbate, naphthyl ascorbate, nicotinoyl ascorbate, monoethyl ascorbyl succinate, cinnamyl ascorbate, thiophene ascorbate, and furfuryl ascorbate.

7. The olefin polymerization catalyst component according to claim 1, characterized in that The ascorbic acid diester compound of the general formula (II) is selected from dimethyl ascorbate, diethyl ascorbate, di-n-propyl ascorbate, diisopropyl ascorbate, di-n-butyl ascorbate, diisobutyl ascorbate, di-tert-butyl ascorbate, di-n-pentyl ascorbate, diisopentyl ascorbate, dicyclopentyl ascorbate, di-n-hexyl ascorbate, dicyclohexyl ascorbate, diheptyl ascorbate, dioctyl ascorbate, dinonyl ascorbate, didecyl ascorbate, dilauryl ascorbate, dimyristyl ascorbate, dipalmityl ascorbate, distearyl ascorbate, and dioctyl ascorbate. The invention can be selected from the group consisting of at least one of ascorbic acid ester, diphenyl ascorbate, dibenzyl ascorbate, diphenylacetate, di-o-chlorophenyl ascorbate, di-m-chlorophenyl ascorbate, di-p-tolyl ascorbate, di-p-methoxyphenyl ascorbate, di-p-methylphenyl ascorbate, m-trimethylphenyl ascorbate, p-nitrophenyl ascorbate, p-fluorophenyl ascorbate, p-trifluoromethylphenyl ascorbate, dicrotonyl ascorbate, dinaphthyl ascorbate, dinicotinoyl ascorbate, monoethyl ascorbyl disuccinate, dicinnamyl ascorbate, dithiophene ascorbate, and difurfuryl ascorbate.

8. The olefin polymerization catalyst component according to claim 1, characterized in that The ascorbic acid tetraester compound of the general formula (III) is selected from the group consisting of tetramethyl ascorbate, tetraethyl ascorbate, tetra-n-propyl ascorbate, tetraisopropyl ascorbate, tetra-n-butyl ascorbate, tetraisobutyl ascorbate, tetra-tert-butyl ascorbate, tetra-n-pentyl ascorbate, tetraisopentyl ascorbate, tetracyclopentyl ascorbate, tetra-n-hexyl ascorbate, tetracyclohexyl ascorbate, tetraheptyl ascorbate, tetraoctyl ascorbate, tetranonyl ascorbate, tetradecyl ascorbate, tetralauryl ascorbate, tetramyristyl ascorbate, tetrapalmityl ascorbate, ascorbic acid At least one of ascorbic acid tetrastearate, tetraphenyl ascorbate, tetrabenzyl ascorbate, tetraphenylacetate ascorbate, tetra-o-chlorophenyl ascorbate, tetra-m-chlorophenyl ascorbate, tetra-p-tolyl ascorbate, tetra-p-methoxyphenyl ascorbate, tetra-p-methylphenyl ascorbate, m-trimethylphenyl kojic acid, p-nitrophenyl kojic acid, p-fluorophenyl kojic acid, p-trifluoromethylphenyl kojic acid, tetracrotyl ascorbate, tetranaphthyl ascorbate, tetranicotinoyl ascorbate, tetraethyl ascorbate succinate, tetracinnamyl ascorbate, tetrathiophene ascorbate, and tetrafurfuryl ascorbate.

9. The olefin polymerization catalyst component according to claim 1, wherein The components of the olefin polymerization catalyst include a titanium compound, a magnesium compound, and an ascorbic acid ester compound; The precursor of the magnesium compound is selected from X n Mg(OR a ) 2-n 、MgCl2·mR a OH, R a 2-n MgX n , MgCl2 / SiO2, MgCl2 / Al2O3, a mixture of magnesium halide and titanium alkoxide, wherein m is 0.1-6, 0≤n≤2, X is a halogen, R a C1-C 20 The hydrocarbon group; The general formula of the titanium compound is TiX N (OR b ) 4-N , where R b C1-C 20 The hydrocarbon group is: X is halogen, and N is 1-4.

10. The olefin polymerization catalyst component according to claim 9, characterized in that The magnesium compound is an alcoholate of magnesium dihalide; or, the magnesium compound is a liquid magnesium compound; or, the magnesium compound is a derivative in which at least one halogen atom in a magnesium dihalide molecule is replaced by a hydrocarbonoxy group or a halogenated hydrocarbonoxy group.

11. The olefin polymerization catalyst component according to claim 9, characterized in that The titanium compound includes at least one of titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, and alkoxy titanium halide.

12. The component of the olefin polymerization catalyst according to claim 11, characterized in that The alkyl titanium halide includes at least one of methoxytitanium trichloride, ethoxytitanium trichloride, propoxytitanium trichloride, n-butoxytitanium trichloride, dimethoxytitanium dichloride, diethoxytitanium dichloride, dipropoxytitanium dichloride, di-n-butoxytitanium dichloride, trimethoxytitanium chloride, triethoxytitanium chloride, tripropoxytitanium chloride, and tri-n-butoxytitanium chloride.

13. The olefin polymerization catalyst component according to claim 9, characterized in that The halogen is at least one of chlorine, bromine and iodine.

14. The component of the olefin polymerization catalyst according to claim 9, characterized in that The molar ratio of the sum of the internal electron donors to the magnesium compound is 0.01-5.0, and the magnesium compound is calculated as magnesium element.

15. The component of the olefin polymerization catalyst according to claim 1, characterized in that When the internal electron donor is a mixture of two of the general formula (I), general formula (II) and general formula (III), the molar ratio of the two internal electron donors is 20:1 to 1:

20.

16. The component of the olefin polymerization catalyst according to claim 1, characterized in that When the internal electron donor is a mixture of the three of general formula (I), general formula (II) and general formula (III), the molar ratio of the feed amount of any one of general formula (I), general formula (II) and general formula (III) to the total feed amount is ≥1 / 20.

17. An olefin polymerization catalyst comprising the catalyst components according to any one of claims 1 to 16 and an organic aluminum compound.

18. The olefin polymerization catalyst according to claim 17, characterized in that The general formula of the organoaluminum compound is AlR c p X (3-p) , where R c is hydrogen or C1-C 20 wherein X is a halogen and p is an integer of 0≤p≤3.

19. The olefin polymerization catalyst according to claim 17, characterized in that The organic aluminum compound includes at least one of a trialkyl aluminum compound, an alkyl aluminum halide, an alkyl aluminum hydride, an alkyl aluminum sesquichloride, and an alkyl aluminumoxane.

20. The olefin polymerization catalyst according to claim 17, characterized in that The molar ratio of the organic aluminum compound to the titanium atom in the components of the catalyst is 1-1000:

1.

21. The olefin polymerization catalyst according to claim 17, characterized in that The raw material composition of the catalyst also includes an external electron donor; The external electron donor is a siloxane compound.

22. The olefin polymerization catalyst according to claim 21, characterized in that The general formula of the siloxane compound is R' t Si(OR”) 4-t , wherein R' and R" are each independently selected from C1-C 18 A hydrocarbon group, t is an integer of 0≤t≤3.

23. The olefin polymerization catalyst according to claim 22, characterized in that R' and R" each contain a heteroatom.

24. The olefin polymerization catalyst according to claim 23, characterized in that The heteroatom includes at least one of N, O, S, P, and Si.

25. The olefin polymerization catalyst according to claim 21, characterized in that The molar ratio of silicon in the external electron donor to titanium in the components of the catalyst is 0.002-100.

26. Use of the olefin polymerization catalyst according to any one of claims 17 to 25 in olefin polymerization.

27. The use according to claim 26, characterized in that The olefins include at least one of ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 3-methyl-1-butene, 4-methyl-1-pentene, butadiene, vinylcyclopentene, and vinylcyclohexene; The polymerization includes homopolymerization or copolymerization; The polymerization temperature is ≤200° C., and the polymerization pressure is ≤10 MPa.

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