Catalyst component for olefin polymerization, catalyst and application thereof

Abstract

The invention provides a catalyst component for olefin polymerization, a catalyst and application of the catalyst component. The catalyst component comprises Mg, Ti, halogen and kojic acid ester internal electron donors, wherein the kojic acid ester internal electron donor has a structure as shown in a formula I: # imgabs0. The catalyst component and the catalyst have high catalytic activity and high biological safety, can reduce the total ash content of polypropylene resin, residual components of the catalyst and toxicity of the residual components, and are especially suitable for production of medical polypropylene materials.

Description

Technical Field

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

[0002] Polypropylene has excellent properties, such as radiation resistance, high heat resistance, high pressure resistance, physiological degradability, good mechanical properties and chemical stability, etc., and is being used more and more widely 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] 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 compounds disclosed in EP0361493 and EP0728724); (3) succinate compounds (such as compounds disclosed in WO9856834, WO0063261, and WO03022894); (4) glycol ester compounds (such as compounds disclosed in WO9856834, WO0063261, and WO03022894); (5) compounds with other functional groups (such as compounds disclosed in CN1105671, CN1242780, and 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. The catalysts prepared by them have medium activity, good stereoselectivity and low price. 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. At present, the use of most phthalate substances has been restricted. In order to improve the performance of polyolefin catalysts, the internal electron donor compound accounts for about 5-20% by weight in the solid catalyst. As a polymerization residual component, it will have a negative impact on the cleanliness of polypropylene, especially when a catalyst containing a high amount of phthalate internal electron donor is used, which will cause a certain degree of reproductive toxicity in the polypropylene. The components remain, limiting its medical use. In addition, the lower the catalyst activity, the greater the amount of catalyst used during polymerization, the more residues, and the less suitable it is for the production of medical polypropylene. Therefore, the development of a catalyst containing a high biosafety internal electron donor compound and having high activity will be conducive to the production of medical polypropylene products and promote the development of medical polypropylene materials. Summary of the invention

[0006] In order to solve the above problems, the purpose of the present invention is to provide a catalyst component, a catalyst and its application for olefin polymerization, the catalyst component and the catalyst have high catalytic activity and high biological safety, and can reduce the toxicity of the catalyst residual components, and are particularly suitable for the production of medical polypropylene materials.

[0007] In order to achieve the above object, the present invention provides a catalyst component for olefin polymerization, which comprises: Mg, Ti, halogen, and kojic acid ester internal electron donor; wherein the kojic acid ester internal electron donor has a structure shown in Formula I:

[0008]

[0009] In Formula I, R 1 , R 2 , R 3 and R 4 are the same or different, each independently selected from H, halogen, C1-C 20 Preferably, R 1 , R 2 , R 3 and R 4 Each of the heteroatoms comprises one or a combination of two or more selected from halogen, N, O, S, P and Si; preferably, R 1 , R 2 , R 3 and R 4 Two or more of them are bonded to each other to form a ring.

[0010] According to a specific embodiment of the present invention, preferably, in Formula I, R 1 , R 2 , R 3 and R 4 the same or different, each independently selected from H, halogen, the following substituents with less than 20 carbon atoms: straight-chain or branched alkyl, cycloalkyl, alkenyl, ester, phenyl, alkylphenyl, phenylalkyl, indenyl, benzyl, halogenated alkyl, alkyl containing heteroatoms, halogenated cycloalkyl, cycloalkyl containing heteroatoms, halogenated phenyl, phenyl containing heteroatoms, halogenated alkylphenyl, alkylphenyl containing heteroatoms, halogenated phenylalkyl, phenylalkyl containing heteroatoms, halogenated indenyl, indenyl containing heteroatoms, halogenated benzyl, benzyl containing heteroatoms, heterocyclic aromatic substituents; the heteroatoms include one or a combination of two or more of N, O, S, P, and Si.

[0011] According to a specific embodiment of the present invention, preferably, in Formula I, R 1 , R 2 , R 3 and R 4are each independently selected from H, halogen, 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 The straight chain or branched alkyl group of 20 carbon atoms or the following substituents within 20 carbon atoms: alkenyl, phenyl, m-chlorophenyl, p-chlorophenyl, o-chlorophenyl, m-methoxyphenyl, p-methoxyphenyl, o-methoxyphenyl, p-methylphenyl, p-nitrophenyl, m-nitrophenyl, benzyl and its derivatives, phenethyl and its derivatives, furyl, pyrrolyl, thienyl and indenyl; more preferably, the alkenyl group includes propenyl, butenyl, pentenyl and hexenyl.

[0012] According to a specific embodiment of the present invention, preferably, in Formula I, R 1 and R 2 Selected from C1-C 20 The hydrocarbon group; R 3 and R 4 Both are H.

[0013] According to a specific embodiment of the present invention, preferably, the kojic acid ester internal electron donor includes kojic acid diacetate, kojic acid dipropionate, kojic acid di-n-butyrate, kojic acid diisobutyrate, kojic acid di-n-valerate, kojic acid diisovalerate, kojic acid di-tert-valerate, kojic acid di-n-hexanoate, kojic acid diisohexanoate, kojic acid dicyclopentacarboxylate, kojic acid di-n-heptanoate, kojic acid dicyclohexylcarboxylate, kojic acid dioctanoate, kojic acid dipelanteate, kojic acid didecanoate, kojic acid di(undecanoic acid) ester, kojic acid dilaurate, kojic acid dimyristate, kojic acid dipalmitate, kojic acid distearate Kojic acid ester, kojic acid dibenzoate, kojic acid diphenylacetate, kojic acid diphenylpropionate, kojic acid di-o-chlorobenzoate, kojic acid di-m-chlorobenzoate, kojic acid di-p-toluate, kojic acid di-p-methoxybenzoate, kojic acid m-trimethylbenzoate, kojic acid p-nitrobenzoate, kojic acid p-fluorobenzoate, kojic acid p-trifluoromethylbenzoate, kojic acid dicrotonate, kojic acid di(1-naphthoic acid) ester, kojic acid dinicotinate, kojic acid di(monoethyl succinate), kojic acid dicinnamate, kojic acid di(α-thiophene)carboxylate, kojic acid difuroate, or a combination of two or more thereof.

[0014] The kojic acid ester compound shown in Formula I can be synthesized by the following preparation methods including but not limited to: preparing by one-step reaction of kojic acid and acyl chloride, as shown in Reaction Formula I. Various acyl chlorides can be selected from commercial products, or the corresponding acyl chloride can be prepared by reacting the acid with the corresponding substituent with thionyl chloride;

[0015]

[0016] According to a specific embodiment of the present invention, preferably, the catalyst component comprises a titanium compound, a magnesium compound, and the kojic acid ester internal electron donor; 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, or a combination of two or more thereof, wherein m is 0.1-6, 0≤n≤2, X is a halogen, R a C1-C 20 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.

[0017] According to a specific embodiment of the present invention, preferably, the magnesium compound is an alcoholate of magnesium dihalide; or, the magnesium compound is a liquid magnesium compound (a magnesium compound dissolved in a liquid); or, the magnesium compound is a derivative of a magnesium dihalide molecule in which at least one halogen atom is replaced by a hydrocarbonoxy group or a halogenated hydrocarbonoxy group; more preferably, it is a hydrocarbonoxy magnesium compound; further preferably, it is an alkoxy magnesium and / or an aryloxy magnesium.

[0018] According to a specific embodiment of the present invention, preferably, the titanium compound includes one or a combination of two or more of titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, and alkoxy titanium halide.

[0019] According to a specific embodiment of the present invention, preferably, the alkyl titanium halide includes one or a combination of two or more 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; more preferably, the titanium compound is titanium tetrachloride.

[0020] According to a specific embodiment of the present invention, preferably, the molar ratio of the kojic acid ester internal electron donor to the magnesium compound calculated as magnesium element is 0.01-5.0:1, preferably 0.05-3.0:1.

[0021] The present invention does not particularly limit the preparation method of the above-mentioned solid catalyst component, which can be carried out according to the following methods:

[0022] Method 1: Magnesium alcoholate or magnesium chloroalcoholate and excess TiCl4 and internal electron donor compound are reacted at a temperature of 80-135°C; preferably, the general formula TiX N (OR b ) 4-N Titanium compounds (where R b C1-C 20 A hydrocarbon group, X is a halogen, N = 1-4; preferably TiCl4) and a general formula of MgCl2·mR a OH adduct (wherein m is a number of 0.1-6, preferably 2-4, and R a C1-C 20 The solid catalyst component is prepared by reacting an internal electron donor with a hydrocarbon group; wherein the general formula is MgCl2·mR a The adduct of OH can be suitably made into spherical shape by the following method: in the presence of an inert hydrocarbon immiscible with the adduct, alcohol and magnesium chloride are mixed, and the emulsion is rapidly quenched, thereby solidifying the adduct in the form of spherical particles (refer to the disclosures of US4399054 and US4469648). The spherical adduct obtained in this way can be directly reacted with the titanium compound, or it can be previously subjected to thermally controlled dealcoholation (80-130°C) to obtain a dealcoholated adduct (wherein the molar number of alcohol is generally less than 3, preferably between 0.1-2.5), and then subjected to the subsequent reaction;

[0023] For example, the adduct or dealcohol adduct is suspended in cold TiCl4 (generally -25-0°C) to react with the titanium compound, and the mixture is heated to 80-130°C and kept at this temperature for 0.5-2 hours, wherein the treatment with TiCl4 can be carried out once or more, and an internal electron donor compound can be added during the treatment with TiCl4, and this treatment can be repeated once or more;

[0024] Method 2: Dissolve the 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, and then mix it with a titanium compound, and precipitate a solid in the presence of a precipitation aid; the solid is treated with an internal electron donor compound to load the internal electron donor compound on the solid, and if necessary, further treated with titanium tetrahalide and an inert diluent; 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 mol, the organic phosphine compound is 0.1-3 mol, the precipitation aid is 0-1.0 mol, and the Ti compound is 0.5-150 mol (calculated as mole of titanium element);

[0025] Method 3: TiCl4 or an aromatic hydrocarbon solution of alkoxy titanium (e.g., toluene, xylene, etc.) is reacted with a dialkoxy magnesium compound such as dialkoxy magnesium (preferably diethoxy magnesium) or diaryloxy magnesium at -25°C-0°C, and halogenated at 80-130°C. The treatment with the aromatic hydrocarbon solution of TiCl4 can be repeated once or multiple times, and the internal electron donor compound is added once or in batches during multiple such treatments. For example, the preparation method of the titanium-containing solid catalyst component disclosed in US5077357 can be used for preparation: ethoxy magnesium, tetraethoxy titanium, o-cresol, ethanol and chlorobenzene are added in sequence, and stirred; TiCl4 / chlorobenzene solution is quickly added to the above liquid, heated to completely dissolve, and then heated to a specific temperature; N2 is used to bubbling away the ethanol reactant and then continued to stir for a certain period of time, then washed once with hot chlorobenzene, washed twice with isooctane, and then dried with N2 to obtain the carrier. Or according to another example: TiCl4, tetraethoxytitanium, ethoxymagnesium and o-cresol are added to chlorobenzene in sequence and stirred; ethanol is added and stirred for 3 hours at high temperature after the ethoxymagnesium is dissolved; hot filtering is performed and then washed once with warm chlorobenzene and once with isooctane, and finally dried with N2;

[0026] Method 4: Magnesium dichloride is preactivated according to existing methods and then treated with excess TiCl4 at a temperature of about 80-135°C, wherein an internal electron donor compound is contained in the solution. The TiCl4 is treated multiple times and the solid is washed with hexane to remove any unreacted TiCl4;

[0027] Method 5: Prepare with reference to the preparation method of titanium-containing solid catalyst component disclosed in CN1208045: 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°C to 200°C, preferably -30°C to 130°C, and an internal electron donor compound is used during the contact process;

[0028] Method 6: Grind anhydrous magnesium chloride and an internal electron donor compound together under conditions where magnesium dichloride is activated, and the product obtained in this way can be treated once or multiple times with excess TiCl4 at a temperature of 80-130°C, and then washed with a hydrocarbon solvent until it is free of chloride ions. A further detailed method is: the product obtained by co-grinding anhydrous magnesium dichloride, a titanium compound and an internal electron donor compound is treated with a halogenated hydrocarbon such as 1,2-dichloroethane, chlorobenzene, dichloromethane, etc., at a temperature between 40°C and the boiling point of the halogenated hydrocarbon for 1-4 hours, and then the product is usually washed with an inert hydrocarbon solvent such as hexane;

[0029] Method 7: A magnesium compound supported on an inorganic oxide such as SiO2, alumina or porous silica gel is used as a carrier for preparation, and then activated by a well-known method, and then treated with an excess of TiCl4 at a temperature of about 80-135°C, and an internal electron donor compound is added during the treatment process.

[0030] The reaction of the above catalyst components leads to the formation of magnesium halide in an active form; general 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 microcrystal suitable for loading Ti is "active magnesium halide". In addition to these reactions, other methods are also known in the literature to make compound starting materials other than magnesium halide form magnesium halide in an active form.

[0031] In any of the methods for preparing the catalyst components, the internal electron donor compound can be added directly as such or in an alternative manner, such as by preparing it in situ using a suitable precursor that can be converted in the desired internal electron donor compound, such as by known chemical reactions such as esterification, transesterification, etc. Typically, the internal electron donor compound is used in a molar ratio of 0.01-5:1, preferably 0.05-3.0:1, relative to the molar number of MgCl2; in addition, the internal electron donor compound can be added simultaneously or separately during the preparation process in batches or in parts, in any order and in any combination.

[0032] The present invention also provides a catalyst for olefin polymerization, which comprises the above catalyst component and an organic aluminum compound.

[0033] 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 C1-C 20 wherein X is a halogen and p is an integer of 0≤p≤3.

[0034] According to a specific embodiment of the present invention, preferably, the organoaluminum compound includes one or a combination of two or more of trialkylaluminum compounds, alkylaluminum halides, alkylaluminum hydrides, alkylaluminum sesquichlorides, and alkylaluminoxanes.

[0035] According to a specific embodiment of the present invention, preferably, the trialkylaluminum compound includes one or a combination of two or more of trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-butylaluminum, tri-n-hexylaluminum, and trioctylaluminum; the alkylaluminum halide includes AlEt2Cl; the alkylaluminum sesquichloride includes Al2Et3Cl3; more preferably, the organoaluminum compound is a mixture of AlEt2Cl and Al2Et3Cl3.

[0036] According to a specific embodiment of the present invention, preferably, the molar ratio of the organic aluminum compound to the titanium atom in the catalyst component is 1-1000:1, more preferably 50-800:1.

[0037] According to a specific embodiment of the present invention, preferably, the raw material composition of the catalyst also includes an external electron donor.

[0038] According to a specific embodiment of the present invention, preferably, the external electron donor is a siloxane compound.

[0039] 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 C1-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 one or a combination of two or more of N, O, S, P, and Si.

[0040] 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, 3,5-dimethylcyclohexylcyclopentyldimethoxysilane, 3-methylcyclohexylcyclohexyldimethoxysilane, bis(3-methylcyclohexyl)dimethoxysilane, 4-methylcyclohexylcyclohexyldimethoxysilane, bis(4-methylcyclohexyl)dimethoxysilane, 3,5-dimethylcyclohexylcyclohexyldimethoxysilane, bis(3,5-dimethylcyclohexyl)dimethoxysilane, tetrapropoxysilane, tetrabutoxysilane, or a combination of two or more thereof.

[0041] According to a specific embodiment of the present invention, preferably, the siloxane compound includes di-n-propyl dimethoxysilane, diisopropyl dimethoxysilane, di-n-butyl dimethoxysilane, diisobutyl dimethoxysilane, di-tert-butyl dimethoxysilane, di-n-butyl diethoxysilane, tert-butyl trimethoxysilane, dicyclohexyl dimethoxysilane, dicyclohexyl diethoxysilane, cyclohexyl methyl dimethoxysilane, cyclohexyl ethyl diethoxysilane, One or a combination of two or more of cyclohexylethyldimethoxysilane, cyclohexylethyldiethoxysilane, cyclopentylmethyldimethoxysilane, cyclopentylmethyldiethoxysilane, cyclopentylethyldimethoxysilane, cyclohexylcyclopentyldimethoxysilane, cyclohexylcyclopentyldiethoxysilane, 3-methylcyclohexylcyclopentyldimethoxysilane, 4-methylcyclohexylcyclopentyldimethoxysilane and 3,5-dimethylcyclopentyldimethoxysilane.

[0042] According to a specific embodiment of the present invention, preferably, the siloxane compound includes 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, tert-hexyltrimethoxysilane, or a combination of two or more thereof.

[0043] 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 0.002-100:1, more preferably 0.01-20:1, and further preferably 0.01-5:1.

[0044] The invention also provides application of the catalyst in olefin polymerization.

[0045] According to a specific embodiment of the present invention, preferably, the olefin includes 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, vinylcyclohexene, one or a combination of two or more thereof.

[0046] According to a specific embodiment of the present invention, preferably, the polymerization comprises ethylene and / or propylene polymerization.

[0047] According to a specific embodiment of the present invention, preferably, the polymerization includes homopolymerization or copolymerization.

[0048] 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, preferably the organoaluminum compound is first added to the polymerization system, then the external electron donor is added, and finally the catalyst component is added.

[0049] 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.

[0050] 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.

[0051] Kojic acid ester compounds are food, medicine and cosmetic additives that have antibacterial, fresh-keeping, freckle removal and whitening effects. In the process of food processing, they can be used as food additives to play the role of preservation, freshness preservation and antioxidant. They can be used to preserve flowers, vegetables and fruits, improve the appearance and internal quality of products, and extend the shelf life of products. Bikojic acid esters are used in cosmetics to remove freckles, are safe to use, and are widely used in the treatment of pigmentation.

[0052] The present invention applies a plurality of kojic acid ester compounds as internal electron donors to the preparation of olefin polymerization catalysts, and the obtained catalysts have high activity and high selectivity. Some kojic acid ester compounds are commercially available common food and drug additives, and other non-commercially available kojic acid ester compounds can be prepared by selecting corresponding acyl chlorides and kojic acid through a one-step reaction, with low production cost, and a wide selection of acyl chloride substituents, 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.

[0053] The six-membered ring skeleton of kojic acid ester contains a variety of oxygen-containing functional groups such as ketone, ether, and ester. It has multiple groups with electron-donating ability, which play a positive regulatory role on the active center of the catalyst, can improve the catalytic activity and reduce the catalyst residue in polypropylene. Kojic acid ester compounds are highly stable and have no side effects on 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 biological toxicity. DETAILED DESCRIPTION

[0054] In order to have a clearer understanding of the technical features, purposes and beneficial effects of the present invention, the technical solution of the present invention is now described in detail below, but it should not be construed as limiting the applicable scope of the present invention.

[0055] The operations for preparing the catalysts in the following examples were all carried out under the protection of high-purity nitrogen.

[0056] The isotacticity of a polymer is determined by the heptane extraction method (extraction with boiling heptane for 6 hours): two grams of a dry polymer sample is placed in an extractor and extracted with boiling heptane for 6 hours. The residue is then dried to a constant weight, and the ratio of the obtained polymer weight (g) to 2 is the isotacticity.

[0057] The bulk density of the polymer was determined using the JB / T 2412-2008 method.

[0058] 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-B300x7.5nm).

[0059] Preparation Example: Synthesis of Kojic Acid Ester Compounds Represented by Formula I

[0060] 1. The synthesis of kojic acid distearate is as follows:

[0061] 13.5g of dry kojic acid (0.095mol) was dissolved in 270ml of dry pyridine, maintained at 20°C under vigorous stirring, and stearic acid chloride was quickly added dropwise at a rate of 10mL / min. The coolant was cooled, and the temperature was gradually raised to about 30°C after the addition was completed. The mixture was kept warm and stirred for 2h to obtain a uniform light yellow reactant. The reaction product was added to 10 times distilled water and stirred evenly, centrifuged, and the filter cake was washed with a large amount of distilled water until there was no pyridine smell (pyridine wastewater recovery treatment). The crude product was dissolved in a mixture of 400mL of ethyl acetate and 10g of activated carbon, heated to reflux, stirred and decolorized for 20min, filtered while hot, and the activated carbon was filtered to obtain a light yellow solution. It was cooled to room temperature to obtain crystals. The crystalline product was filtered and washed with cold ethyl acetate 2-3 times. The filter cake was fully dried at 70°C to remove moisture and ethyl acetate to obtain the product kojic acid distearate with a yield of 80%.

[0062] 2. Other kojic acid ester compounds (a2-a25) were prepared by the above-mentioned route. The starting materials were selected from acyl chlorides and kojic acid with corresponding substituents. The structures and NMR results of compounds a2-a25 are shown in Table 1.

[0063]

[0064] Table 1 Kojic acid ester compounds shown in formula I

[0065]

[0066]

[0067]

[0068] Preparation of catalyst components

[0069] Example 1

[0070] This embodiment provides a catalyst component, and the preparation method thereof is as follows:

[0071] In a 500 ml 5-necked flask with nitrogen fully replaced and stirred, 10 g of MgCl2·2.5C2H5OH microspheres and 150 mL of titanium tetrachloride were added to prepare a suspension, then maintained at -15°C for one hour, slowly heated to 80°C, 3.1 g (5 mmol) of kojic acid distearate was added, and then the temperature was continued to rise to 110°C and kept constant for 1 hour, and then the liquid was filtered clean, and the obtained solid was washed 3 times with 120 mL of titanium tetrachloride at 110°C, and then washed 4 times with 150 mL of hexane at 60°C, the liquid was filtered off and dried to obtain a solid catalyst component E1. The titanium content, internal electron donor content and polymerization data of the solid catalyst component are shown in Table 2.

[0072] Example 2-25

[0073] Examples 2-25 each provide a solid catalyst component E2-E25, the preparation process of which is as shown in Example 1, except that kojic acid distearate is replaced with 5 mmol of compounds a2-a25 in Table 1 in sequence.

[0074] Embodiment 26

[0075] This embodiment provides a catalyst component E26, and the preparation method thereof is as follows:

[0076] In a 500ml 5-necked flask with nitrogen fully replaced and stirred, add 10g anhydrous magnesium chloride, 150mL toluene, 17mL epichlorohydrin and 16mL tributyl phosphate at room temperature, heat to 50°C with stirring, and maintain for 2 hours, the solid is completely dissolved, then add 2.40g phthalic anhydride, and maintain for another hour. The solution is cooled to -25°C, 110mL 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, 3.1g kojic acid distearate is added, and the temperature is maintained at 80°C for 1 hour. After filtering, it is washed twice with 200mL toluene, and then 120mL toluene and 80mL titanium tetrachloride are added. The temperature is continued to rise to 110°C, and the temperature is kept constant for 2 hours, and then the liquid is filtered clean, and the treatment is repeated once. The liquid is filtered off, and the obtained solid is washed once with 100mL dichloroethane and 4 times with hexane, and the solid catalyst component E26 is obtained after drying. The titanium content, internal electron donor content and polymerization data of the solid catalyst component are shown in Table 2.

[0077] Embodiment 27

[0078] This embodiment provides a catalyst component E27, and the preparation method thereof is as follows:

[0079] 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, and 25mL of titanium tetrachloride was added dropwise at -15°C. After the addition was completed, the temperature was slowly raised to 0°C, and then 50mL of titanium tetrachloride was added dropwise, and then the temperature was slowly raised to 80°C, 3.1g of kojic acid distearate was added, and then the temperature was continued to be raised to 110°C and kept constant for 2 hours, and then the liquid was filtered clean to filter out the liquid, and the obtained solid was washed 3 times with 100mL of titanium tetrachloride at 125°C, and the obtained solid was washed 4 times with 120mL of hexane at 60°C, the liquid was filtered out and dried to obtain a solid catalyst component E27.

[0080] Comparative Example 1

[0081] This comparative example provides a catalyst component D1, and its preparation process is the same as that of Example 1, except that kojic acid distearate is replaced by 5 mmol of di-n-butyl phthalate (DN).

[0082] Comparative Example 2

[0083] This comparative example provides a catalyst component D2, and its preparation process is the same as that of Example 1, except that kojic acid distearate is replaced by 5 mmol of 9,9-dimethoxyfluorene (FLU).

[0084] Comparative Example 3

[0085] This comparative example provides a catalyst component D3, and its preparation process is the same as that of Example 1, except that kojic acid distearate is replaced by 5 mmol of acetyl tributyl citrate.

[0086] polymerization

[0087] The solid catalyst component obtained above was used as a component of an olefin polymerization catalyst to carry out polymerization evaluation:

[0088] 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 methylcyclohexyldimethoxysilane hexane solution and 10mg of the prepared 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 stirring is stopped, the reaction product is discharged, and the polymer is obtained by drying. The polymerization data is shown in Table 2.

[0089] Table 2

[0090]

[0091]

[0092] The catalysts of the kojic acid ester compounds as internal electron donors of Examples 1-25 are significantly more active than the catalysts of the internal electron donor compound of acetyl tributyl citrate (a type of biosafety additive) under the same preparation conditions, and are more active than the catalysts of the phthalate internal electron donors most commonly used in industry (polymerization number 28). It can be seen that kojic acid ester compounds can be used as an efficient substitute for the reproductively toxic phthalate internal electron donors. In addition, 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 kojic acid ester compounds as internal electron donors of Examples 1-25 of the present invention are comparable to those of the fluorene diether catalyst (polymerization number 29), and some examples have higher activity. Therefore, the kojic acid ester internal electron donors of the present invention have high biosafety, and the prepared catalysts have high activity, and are particularly suitable for the production of medical polypropylene products.

Claims

1. A catalyst component for olefin polymerization, comprising: Mg, Ti, halogen, kojic acid ester internal electron donors; in, The kojic acid ester internal electron donor has a structure shown in Formula I: In Formula I, R 1 , R 2 , R 3 and R 4 are the same or different, each independently selected from H, halogen, C1-C 20 Preferably, R 1 , R 2 , R 3 and R 4 Each of the heteroatoms comprises one or a combination of two or more selected from halogen, N, O, S, P and Si; preferably, R 1 , R 2 , R 3 and R 4 Two or more of them are bonded to each other to form a ring.

2. The catalyst component according to claim 1, wherein In Formula I, R 1 , R 2 , R 3 and R 4 the same or different, each independently selected from H, halogen, the following substituents with less than 20 carbon atoms: straight-chain or branched alkyl, cycloalkyl, alkenyl, ester, phenyl, alkylphenyl, phenylalkyl, indenyl, benzyl, halogenated alkyl, alkyl containing heteroatoms, halogenated cycloalkyl, cycloalkyl containing heteroatoms, halogenated phenyl, phenyl containing heteroatoms, halogenated alkylphenyl, alkylphenyl containing heteroatoms, halogenated phenylalkyl, phenylalkyl containing heteroatoms, halogenated indenyl, indenyl containing heteroatoms, halogenated benzyl, benzyl containing heteroatoms, heterocyclic aromatic substituents; the heteroatoms include one or a combination of two or more of N, O, S, P, and Si.

3. The catalyst component according to claim 2, wherein In Formula I, R 1 , R 2 , R 3 and R 4 are each independently selected from H, halogen, 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 The straight-chain or branched alkyl group of 20 carbon atoms or the following substituents within 20 carbon atoms: alkenyl, phenyl, m-chlorophenyl, p-chlorophenyl, o-chlorophenyl, m-methoxyphenyl, p-methoxyphenyl, o-methoxyphenyl, p-methylphenyl, p-nitrophenyl, m-nitrophenyl, benzyl and its derivatives, phenethyl and its derivatives, furyl, pyrrolyl, thienyl and indenyl.

4. The catalyst component according to claim 1, wherein In Formula I, R 1 and R 2 Selected from C1-C 20 The hydrocarbon group; R 3 and R 4 Both are H.

5. The catalyst component according to claim 1, wherein The kojic acid ester internal electron donor includes kojic acid diacetate, kojic acid dipropionate, kojic acid di-n-butyrate, kojic acid diisobutyrate, kojic acid di-n-valerate, kojic acid diisovalerate, kojic acid di-tert-valerate, kojic acid di-n-hexanoate, kojic acid diisohexanoate, kojic acid dicyclopentacarboxylate, kojic acid di-n-heptanoate, kojic acid dicyclohexylcarboxylate, kojic acid dioctanoate, kojic acid dipelanteate, kojic acid didecanoate, kojic acid di(undecanoic acid) ester, kojic acid dilaurate, kojic acid dimyristate, kojic acid dipalmitate, kojic acid distearate, kojic acid dibenzoate , kojic acid diphenylacetate, kojic acid diphenylpropionate, kojic acid di-o-chlorobenzoate, kojic acid di-m-chlorobenzoate, kojic acid di-p-toluate, kojic acid di-p-methoxybenzoate, kojic acid m-trimethylbenzoate, kojic acid p-nitrobenzoate, kojic acid p-fluorobenzoate, kojic acid p-trifluoromethylbenzoate, kojic acid dicrotonate, kojic acid di(1-naphthoic acid) ester, kojic acid dinicotinate, kojic acid di(monoethyl succinate), kojic acid dicinnamate, kojic acid di(α-thiophene)carboxylate, kojic acid difuroate, or a combination of two or more thereof.

6. The catalyst component according to any one of claims 1 to 5, wherein The catalyst component comprises a titanium compound, a magnesium compound, and the kojic acid ester internal electron donor; 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, or a combination of two or more thereof, 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.

7. The catalyst component according to claim 6, wherein The magnesium compound is an alcoholate of magnesium dihalide; Alternatively, the magnesium compound is a liquid magnesium compound; Alternatively, the magnesium compound is a derivative of a 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.

8. The catalyst component according to claim 6, wherein The titanium compound includes one or a combination of two or more of titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, and alkoxy titanium halide; Preferably, the alkyl titanium halide includes one or a combination of two or more 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; Preferably, the titanium compound is titanium tetrachloride.

9. The catalyst component according to claim 6, wherein The molar ratio of the kojic acid ester internal electron donor to the magnesium compound is 0.01-5.0:1, preferably 0.05-3.0:1, and the magnesium compound is calculated as magnesium element.

10. A catalyst for olefin polymerization, comprising the catalyst component according to any one of claims 1 to 9 and an organic aluminum compound.

11. The catalyst according to claim 10, wherein The general formula of the organoaluminum compound is AlR c p X (3-p) , where R c is hydrogen or C1-C 20 A hydrocarbon group, X is a halogen, and p is an integer of 0≤p≤3; Preferably, the organoaluminum compound comprises one or a combination of two or more of trialkylaluminum compounds, alkylaluminum halides, alkylaluminum hydrides, alkylaluminum sesquichlorides, and alkylaluminoxanes; Preferably, the trialkylaluminum compound includes one or a combination of two or more of trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-butylaluminum, tri-n-hexylaluminum, and trioctylaluminum; the alkylaluminum halide includes AlEt2Cl; the alkylaluminum sesquichloride includes Al2Et3Cl3; Preferably, the organoaluminum compound is a mixture of AlEt2Cl and Al2Et3Cl3.

12. The catalyst according to claim 10, wherein The molar ratio of the organic aluminum compound to the titanium atom in the catalyst component is 1-1000:1, preferably 50-800:

1.

13. The catalyst according to claim 10, wherein The raw material composition of the catalyst also includes an external electron donor.

14. The catalyst according to claim 13, wherein The external electron donor is a siloxane compound.

15. The catalyst according to claim 14, wherein 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; Preferably, R' and R" each contain a heteroatom; Preferably, the heteroatom includes one or a combination of two or more of N, O, S, P and Si.

16. The catalyst according to claim 13, wherein The molar ratio of silicon in the external electron donor to titanium in the catalyst component is 0.002-100:1, preferably 0.01-20:1, and more preferably 0.01-5:

1.

17. Use of the catalyst according to any one of claims 10 to 16 in olefin polymerization; Preferably, the olefin includes one or a combination of two or more 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; Preferably, the polymerization comprises ethylene and / or propylene polymerization; Preferably, the polymerization comprises homopolymerization or copolymerization.

18. The use according to claim 17, wherein: The polymerization temperature is ≤200°C, preferably 20-100°C, more preferably 40-80°C; The polymerization pressure is ≤10 MPa, preferably 0.3-5 MPa.

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